 |
|
NOTE: This article was originally written
in early 1994 and published in ‘Sports Car Talk’, the magazine of the Sports
Car Club of NZ. I have given it a quick once over to correct a couple of
minor errors. Prices are in $NZ. If you want to know more, please do not
hesitate to contact me.
Phil Bradshaw
WHEN 16 VALVES JUST ISN'T ENOUGH! (Or 'Easy is only
Skin Deep')
This article is a follow up to one I wrote in early
1993 ago concerning the installation of a 16 valve Toyota 4AGE into my
car. I apologise to the casual reader who may find the content excessive,
but hope that it is of use to those contemplating buying one of these marvelous
little engines, or indeed contemplating any engine installation. As before,
I have endeavoured to make the article as accurate as possible, and can
be contacted at the above address if you would like to know more. And now
on with the story...
Recite after me: 'In 1992 I built up a Leitch Supersprint
Lotus 7 Replica (similar to a Fraser 7)...' You know the story! Well, what
you may not know was that at the Practice Day at Taupo back in May 1994
I put in one 'race' and retired due to a nasty little rattle emanating
from my motor...
Expert trackside opinion was consulted, and the general
consensus was that my hitherto faithful 1983 Blue and Black top 4AGE had
killed a conrod bearing. It still ran fine, oil pressure was OK and although
the rattle was definitely there, it was not too bad (well, as they say
- 'Is it broken bad?' - Have you ever seen anything broken good?)...Anyway,
I digress.
So, I spent the rest of the day marshaling, which
was a bit of an irk, as I felt I was doing really well until the engine
died, and was looking forward to more laps. I figured it was better to
retire and let the engine live to be able to drive home, rather than destroy
the motor completely. End of the day we drove back to Auckland without
a hitch, and I drove around, albeit gently as it is still my only car,
until Queen's Birthday weekend when I pulled the car off the road. I was
fortunate that a good friend was overseas with work for four months and
had loaned me his car.
The Leitch had been on road for 18 months at that
stage, and through one thing or another, such as me heading overseas with
work, had been driven for about 16 of those months, and clocked up 23,000
miles, on top of the 84,000 km on the engine initially. I guess having
the motor die at about 115,000 km, given the life its had, is pretty good
really.
My car was in need of some major TLC, which I must
confess was not part of my plans when I built it initially, but circumstance
went against me - I had a rear mudguard crack and mostly tear off when
I flicked up a muffler lying on the motorway, ripping the nutserts out
of the aluminium skin. I was rear ended by a Gentleman who not only didn't
notice the red traffic lights but really made my day by being a sickness
beneficiary with no insurance. Legal proceedings are being pursued, damage
was minor but necessitated reskinning the back of the car - $1450 worth
of work, but a very good job by Terry's team at Terry's Panelworks in East
Tamaki. (Note - some 2 years later I am still only 50% successful in getting
money out of the other driver...)
I had a minor wiring loom fire, the cause of which
is still a bit of a mystery, and I can only guess that some stray condensation
shorted across terminals under the scuttle. Why it took 18 months to occur
I have no idea. Then there was the broken panhard rod mount - mine is the
only Leitch to ever have this happen, which was small consolation when
it happened at 5 pm 30 km north of Taumaranui on Easter Thursday, when
I was heading towards Wellington! Fortunately a local welder took pity
on our sob story and did a patch up job.
A few other minor niggles had got to me, so a major
rebuild commenced. How major? Well, it took me 3 months to build the car
initially, but I managed to stretch the rebuild out to almost six. Admittedly
I had more time available, like a solid month off work, when I first built
it, but as you can appreciate, I have virtually completely rebuilt the
whole car, and don't intend doing so again. Mind you, that is what I said
when I built it originally...
On to more interesting stuff, and the main thrust
of this article: what do I do about the engine? I talked to a number of
people, rang around and scratched my head a lot. As best I could tell,
the options were:
 |
rebuild the 4AGE, |
 |
replace the 4AGE, or |
 |
repower the car with something
else. |
I'll say now that I had no money, but was very conscious
of the old adage that the cheapest option is not always the best, hence
I did what I consider to be all the homework first.
Rebuilding the 4AGE was going to be a major, as the
engine always smoked a little on deceleration, had a dead bearing or worse,
had a worn clutch, delivered 118 hp/88 kW when new (and I was hungering
for more) (sound familiar?), and had oil problems resulting in it turning
into a two stroke on occasions. Now, all these maladies were curable (except
for the power output - remember I used the injection, and was basically
restricted from putting in hotter cams as the computer can't handle it),
but the question was at what cost? I reckoned on at least $1000 to do the
job properly, even if I did all the spanner work myself.
Next option was replacing the engine. I rang around,
and found I could get a similar vintage Blue and Black top for $550 cash
from Engine Imports. There was a choice of two, which were the last of
a large shipment. Both were incomplete, and with no computer or wiring
loom, however I had all the missing bits available from my old engine.
Thing is, such an engine is probably not much healthier than my old one,
and to me three month's warranty is not sufficient consolation on an 11
year old motor that is going to be given a hard time, and must be reliable
as it is normally my only transport.
Furthermore it would still require modifying to prevent
it suffering from the oil problem, and it would be prudent to replace cam
belt, etc. At the end of the day, I would be conceivably driving on an
engine that was no better than the one I broke, and more than likely to
be on its last legs, which might last 1-2 more years if I was lucky.
So, that left option three. I talked to more people,
and paid a visit to Neil Fraser, who listened to what I was saying and
showed me a collection of engines he head lying around. We talked about
cost and output and installations etc, and I came down to three options:
 |
Red top 16V 4AGE |
 |
20 Valve 4AGE |
 |
3SGE |
Purchase of a red top 4AGE would cost around $1500,
and would deliver about 135 hp/100 kW. The engine would be up to about
5 years old, I think. That was the good news. Bad news was it was an East/West
front wheel drive motor, so the inlet manifold faced backwards, and the
computer is different, necessitating a full rewire on the engine side.
A 20 Valve 4AGE would deliver 158 hp/117 kW and be
up to 3 years old, however have the same problems as above, plus an air
flow meter to squeeze under the bonnet somewhere (as opposed to the map
sensor fitted to the 16 Valve), and cost $2500.00.
The 3SGE is the latest 2 litre motor fitted to the
MR2, and is looking like being the formula motor for the Clubmans' Series.
It has an inlet manifold for the injection that wraps over the head, which
makes it too high to fit in a Seven - the solution being to put twin side
draughts on it. This is fine if you already have a 4AGE or similar running
on twin side draughts, however if you are like me, adoption of the engine
means that you need to buy:
| engine |
$2500 |
| manifold |
$ 220 |
| carbs |
$1100 |
| jets/throats |
$ 400 |
| linkages |
$ 200 |
| air filters |
$ 250 |
| bell housing |
$ 400 |
| black box to make distributor
go |
$ 400 |
| Total: |
$5470 |
Add to this new exhaust system, low pressure fuel
pump, new engine mounts, shortened sump, plus the other complications involved
in turning an East/West motor North/South mentioned above, and it all looked
too expensive for me. Which is a damn shame because the motor puts out
180 hp/135 kW in stock form, even more on carbs, and a fair whack of torque.
If I ever got rich (or someone paid me a lot of money
for my car and I built a new one), I'd like to attempt building up a 3SGE
on injection with a custom built inlet manifold to fit under the bonnet,
and either the stock computer or an aftermarket one. I reckon it ought
to be possible, and believe it is an option being looked at by one or two
people.
I believe that the rationale for adopting this engine
as the Clubmans' motor, is that people were spending $15,000 on a 4AGE,
getting 230 hp and eating those of us with fewer resources. The 3SGE offers
a hell of a lot of power, out of a stock engine, that once set up should
last for quite a while.
Granted that speed costs, we all know that, and realistically
spending 5 or 6 grand to get 180+ hp out of possibly a two year old stock
motor is bloody good value for money. Unfortunately it was also beyond
my means. Additionally, perhaps mistakenly, I was concerned about my standard
T 50 alloy case Toyota AE 86 Levin gearbox and Escort diff handling the
power and torque. I know they are both reasonably beefy, and a seven doesn't
weigh much, but as I keep saying, my car must be reliable, and I'm just
not as rich as I'd like to be.
As I said, if I was building from scratch I might
do things different, and would probably go injected 3SGE, 5 speed and fully
independent based on a LSD RX7 rear end. Dreams are free, thank God!
So, after much deliberation, I decided to go for
a 20 Valve, for the following reasons:
 |
I was concerned that a replacement
blue and black top would see me back in the present situation in 12 months
time (if I was lucky), and would not cure my wish for more power or alleviate
the ... |
 |
... oil surge smoke (Which
I could fix by using a surge/collection tank, external breather etc, however
I was concerned that when cornering at high RPM oil was pumping into the
head quicker than it drained), |
 |
rebuilding my motor would
cost at least $1000, and again not cure the desire for more grunt or the
oil surge smoke, and for approximately $500 more ... |
 |
... purchasing a red top
would solve the desire for increased power and oil surge smoke due to redesigned
oil returns, however for the effort involved in fitting the engine to the
car, and spending a further $1000 ... |
 |
... the 20 valve offered
a state of the art motor with a very high output, that should last a long
time, should bolt in relatively easily, and cost an 'affordable' (or is
it justifiable?) amount of money. |
Wait a minute, I thought I had no money. All I can
say is God Bless my Bank Manager! Poor man was subjected to my analysis
of what I wanted to do, and refinanced a loan that I got initially to build
the car with, and had almost paid off. I think he would have given me the
money just to get me out of his office!
At the end of the day, getting my car back on the
road has not been cheap, however as I have already explained, I have undertaken
a complete rebuild, with the re-engining of the car being just one aspect
of it.
So, what is a 20 Valve? I must confess to not knowing
a lot about them, but what I do know is that it is a heavy duty 1587 cc
4AGE bottom end with a 20 valve head (how surprising). It has three inlet
and two exhaust valves per cylinder, and variable inlet valve timing. My
understanding is that at high RPM a solenoid valve directs oil through
an additional camshaft drilling that fills up a fluid coupling within the
inlet cam drive pulley, rotating the camshaft 15 degrees ahead of the periphery
of the pulley, thereby advancing the camshaft (and the inlet valve timing)
by 15 degrees.
Otherwise the motor is pretty normal with a knock
sensor, air flow meter and not one, but four throttle bodies - the inlet
system looks a lot like a collection of stubby sidedraught carbies sucking
from an air box.
The 20 Valve is designated 4AGE-10, whatever that
means, and has 'TWIN CAM 20' on the cam cover (which makes everyone think
it is a two litre), and '4 Throttle' on the inlet air box. The cam cover
is silver and the plug leads are hidden beneath a central cover. The distributor
drives directly off the back of the exhaust cam, and the variable cam timing
solenoid sits in about the same position as the normal distributor mount.
Ordinarily the motor lives in a Toyota AE 101 Apex
or Levin, both of which are front drive and apparently Japanese domestic
models only. I have seen a couple in New Zealand, one of which was a 16
valve, and there was a 20 valve advertised for $30k, but I didn't get a
chance to have a look at it. They come automatic and manual, and run 11.25:1
compression, as far as I know, which is why they aren't available outside
Japan, due to the requirement for high octane unleaded.
I bought my engine from Neil Fraser, and received
motor (fanbelt to clutch, air flow meter to extractors, alternator and
starter motor), uncut loom, computer, coil, igniter etc, and a wiring diagram.
Neil also gave me a warranty that everything was in going order, as unless
the motor rattled or smoked from start up, it was unlikely to die in the
foreseeable future.
This cost me $2500 cash, which I thought was reasonable,
bearing in mind other prices I had been quoted for a 20 Valve. Furthermore
the engine arrived in NZ only 2 days before I bought it, and I had the
choice of two. Additionally it came from the same crowd in Japan that Neil
uses to source his FC7 engines, so I figured it would be a safe bet. I
also felt happier dealing with Neil as he knows what he is on about, and
if he sells you a motor with the statement that 'all you need is here',
then it is. I was concerned about having an engine from an importer that
I would not be able to get to go without paying someone lots of dollars
for a few seemingly insignificant parts.
Neil is not really in the engine supply business,
and as I hadn't actually bought a Fraser 7, he explained that I was pretty
much on my own (ie they would not hold my hand during the installation),
but he did give me the number of a guy who did work on the 20 valve they
raced in the Targa Tasmania. I thought that was fair enough, and at the
end of the day, I think I managed quite well on my own.
Incidentally, Strong Brothers at Penrose was recently
selling a 1600 Honda VTEC motor, gearbox, computer, loom etc for $2000
inclusive. Be warned the damn things rotate backwards though, which is
fine if you are building a mid engined car, otherwise I guess you have
to turn your diff upside down...
I talked to Peter Sullivan in Southland, who is building
a Leitch up slow-time with a 20 valve, but he has yet to get it running.
He was planning to use an aftermarket computer, as is Darryl Jeffares.
Neil Fraser's TT one was extensively modified, and other than one rumoured
to be running in a Chevron, I have not heard of any others actually on
the road, or that are running in a stock configuration.
First hurdle was deciphering the wiring diagram,
which was all in Japanese. I quickly discovered that Japanese is a very
complex written language, so much so that it can apparently take until
late teens before people can really understand a newspaper. One of the
guys at work lived in Japan until he was 12, and he managed to decipher
about a third of it. A friend of a friend, majoring in Asian languages,
got stumped due to the technical content, and I was on the verge of placing
an add when my flatmate, who is a sales rep, came home from a day trip
up North with a Japanese exchange student that his Boss was hosting. She
was being picked up in half an hour, so I collared her and she translated
the entire lot!
Whilst chipping away at the wiring diagram I was
also installing the engine in the car as a trial fit. As it is a front
wheel drive motor, there are a few differences in component configuration.
Firstly the starter motor is on the inlet side of the engine, which would
not clear my foot well and also not mate with the gearbox bellhousing.
The solution was to use the old motor's flex plate, starter motor and bellhousing,
etc. This all bolted straight up, however if you buy a 20 Valve and a T
50 gearbox as separate units, you will not have the flex plate. All is
not lost, as the 20 Valve has the blank where the rear wheel drive starter
motor goes, so with a bit of care, accurate cutting can be done, followed
by a simple amputation of the now redundant other position.
As I said, the gearbox mounts straight up, and I
re-used the two block to bellhousing supports, however one of the holes
didn't line up, so I am one bolt short, but I appear to have got away with
it. Darryl's motor has a big cast aluminium bracket that does this job,
but his engine was out of an automatic, and the casting does not line up
with the bell housing. He is contemplating his options at the moment.
The Leitch uses the central engine mounts on the
block, and apart from drilling a hole to clear a dowel pin, my old mounts
mated exactly. I believe the FC7 uses a different location on one side,
and the 20 valve block is different at that point, necessitating a new
mount, which is not really a biggie.
So, next step was installation. The motor and box
went straight in (well, as straight in as any attempt at squeezing a motor
into a 7 goes!), except for having to stop half way to lop off a chunk
of redundant bracketry that was interfering with my pedal box. I installed
the motor complete, except for the air box and loom.
Unfortunately getting the motor in place was the
easy bit. The challenge was getting the EFI system to fit! There were two
main problems: the air box was too big to fit, and the air flow meter had
to go somewhere. Additionally in the standard East/West set up, the engine
sits with the exhaust manifold forward, which makes it sensible to locate
the radiator hose connections on that side, at the flywheel end of the
head due to all the cam drives and variable timing bumpf at the front.
Unfortunately, when you rotate the motor North/South, it puts the inlet
at the back of the block, and you've got an exhaust manifold to negotiate
around as well! The thing to remember is that this engine is going into
that shrine to minimalism known as a Seven, which was initially designed
to take a 1000cc pushrod motor, not a twin cam fuel injected beastie.
Anyway, I digress, yet again. The decision on the
Air Flow Meter had to be made first, as it is attached to the Air Box via
a bit of flexible tube (which I didn't have, and probably wouldn't have
been much good anyway), which mates into the flywheel end of the airbox.
Dilemma: do I mount the air flow meter behind the engine, above the foot
wells, where it gets all that nice, warm, low density air, or do I perform
some surgery on the airbox and have the air flow meter attached at the
front of the engine? Trouble then is that it would be sucking from directly
behind the radiator...
I thought about these things, and figured that the
old motor basically sucked from behind the radiator, and still went ok,
and I had seen a picture of a Fraser (I think) with an air flow meter,
sitting on the footwells. I've gone with this option, as there is a little
more room on the footwells. Additionally I had to cut the airbox to fit
below the bonnet, and after surgery the front of the box wasn't big enough
to fit the inlet tube onto anyway!
The Airbox was a bigger worry, literally - it sat
too high (above the bonnet line), too low (its base wanted to sit where
a spaceframe tube lived), and too long (it interfered with my pedal box
cover). As you may recall, a Fraser with a 4AGE on injection has a bonnet
bulge to clear the manifold, whereas the Leitch does not, due to chopping
the inlet manifold by 30 mm. I could have made up a bulge for the bonnet,
but it looked too hard, and I figured it would be a big, ugly bulge (I
personally think the wee bulge on the Fraser is quite elegant and subtle,
but this one would be in a different league!), and it still wouldn't cure
the other areas of interference.
As a sideline, if you have the luxury of space, particularly
height, as you may do in a Lynx or a 'normal' car, you can quite literally
bolt the air box on upside down, which will then put the inlet from the
Air Flow Meter towards the front as well, or If you don't mind a bonnet
bulge, this may be a workable solution.
Of course the other option is to build your own air
box, which is what I considered initially. After all, people have been
doing it with carburettors for years. I went and had a talk to the friendly
chaps at Weber Specs, as I figured they'd have the good oil on such things.
My first plan was to construct a plastic air box out of suitably sized
PVC conduit, drainpipe and glue, with a good coat of paint on completion
to cover my sins. This appeared to have merit, until the Weber guys started
talking about sufficient volume for intake depression when the throttle
is floored until the air flow increases and other scary things. Like everything
I guess, it all appears simple from a cursory glance, but gets more complex
as you look into it.
Additionally the Toyota has intake trumpets within
the air box, which are curved like a cow horn and about 150 mm long, as
the box is deep but not wide. I thought more about it and decided that
in order to get a decent volume within the box I would have to use a large
diameter tube that again would not fit under the bonnet, and probably look
rude. Time for plan two. I rationalised that Escort Rally Cars survived
for years on stubby trumpets (or none at all), due to the proximity of
the carbs to the strut tower, and they still produced heaps of grunt in
race tune, so I figured I could chop down the steel air box and put some
stubby (ie inch long) trumpets in later. (The throttle body inlet is 47mm
wide and vaguely similar to a Dellorto bolt pattern).
With a plan of action, it was time to work out where
to chop the box. I figured that the actual air box volume wasn't that great,
as the trumpets took up most of it, so I reckoned that reducing the air
box and turfing the trumpets (with only short replacements) would work.
The Weber Guys agreed in principle, so away I went. I then had to suss
out where to chop the box. Of course it isn't parallel, but with a bit
of cunning, I sliced 30 mm out of the bottom half and with a small amount
of tin bashing got all the seams to line up close enough for welding.
I can't weld to save myself, but I talked nicely
to one of the guys at work who is a very good welder, and he did it for
me. He had a bit of a mission as the airbox halves are basically laminated
from thin sheets of steel (they are quite deep pressings), and proved very
difficult to weld. Ultimately he used stainless welding rod to get the
job done. Next step was to take 15 mm out of the rear wall to clear the
pedalbox. What was really scary was the amount of time it took me to section
the box, make up the new inserts, have it welded and grind the welds smooth
on completion - the Guy who supervises the Welding shop reckoned that as
a commercial job it would probably be worth about $700 to have it all done...
That done, I could finally bolt the bottom half of
the air box to the throttle bodies in the car. Naturally it was still too
high with the top half of the box in place, so it was time to put the nose
cone and scuttle on and start stretching tape between the two, to get the
bonnet profile against the air box. After much head scratching a decision
was made, the top of the box was lopped off, and a new one welded on. The
net result is an air box that clears bonnet, spaceframe and pedal box by
10-15 mm, which is about the same clearances as the original 16 valve 4
AGE installation. Not forgetting that I have very rigid engine mounts,
so the motor doesn't move about much (except when the sump hits the road).
The Air Flow Meter was a tight squeeze, particularly
with trying to site the ignition coil/igniter pack, battery and windscreen
washer tank in the same area, not forgetting pedal box and master cylinders.
I eventually overcame this, but not before spending a considerable amount
of time and effort with cardboard and then aluminium mounting brackets.
I swear I made 5 of each before getting it right. I used a modified sidedraught
K&N airfilter on the inlet to the air flow meter. Next step was connecting
the air flow meter to the air box. Trouble was, it needed 70 mm tubing.
After much anguish, I used a section of Escort heater concertina tube,
that normally connects the heater to the eyeball vent in the dashboard.
I was intending to use it only as a temporary measure, but it seems to
work fine so far, and looks OK as well. Time will tell, I guess.
I reused the standard 16 valve exhaust manifold as
I could not afford to make a new exhaust. The cast manifold required slight
modification to the outermost mounts but otherwise matched right up. I
intend to use the factory extractors as part of a 4 into 2 into 1 system
in the near future.
There was the usual messing around with fuel lines
etc to get the hoses to mate up with the right bits, as again the inlet
and outlet from the fuel rail were at opposite ends to the 16 valve. I
used the new alternator with the old mount and belt type, as it was more
compact than the 20 Valve arrangement, which uses an idler pulley, I guess
in an effort to clear some obstacle that exists in the Apex/Levin. In so
doing, I had to modify the dipstick tube mount, as it connects to the other
alternator bracket. I just copied the 16 valve installation, whereas Darryl
has just cut the rest of the 20 Valve alternator mount bracket off beyond
the dipstick mount. You cannot swap the dipstick with the 16 valve as the
levels in the sump are different.
The throttle linkage was another source of fun and
games - the 20 Valve has a cunning mechanism utilising levers and pivots
that sits above the throttle bodies, with the cable inlet from the front
of the engine. Two problems here - the linkages sit above the bonnet line,
and the cable comes in from the wrong end. I figured I'd just rotate the
whole assembly 180 degrees and mount it underneath the throttle bodies,
but after much messing to get angles right discovered the spaceframe was
in the way anyhow! I ended up using a bottom entry direct wire set up similar
to a twin sidedraught installation, which works really well, but needs
a little modification to some angles to prevent the wire abrading the side
of the adjusting barrel. I used bicycle brake cable components for the
set up.
The oil filler cap has a small spine on it for you
to grab and quarter turn to release it, but of course it hit the bonnet
also. The solution was to chop the spine off, but the wily Japanese made
it hollow, so I machined the top flat and superglued a flat piece of 'Engine
Oil' engraved plastic to the top. Looks like a bought one and still easy
to undo. The injector wires are run in a small square section conduit the
sits above the injector heads, screwed to the throttle body castings, which
also hit the bonnet (surprise, surprise). Initially I was going to turf
it and just use concertina cable coverings, but ended up mounting it below
the injector heads, where it clears the bonnet just fine, mounting on the
redundant throttle linkage points.
I threw away the vacuum lines that went from the
engine to bits of the Apex/Levin that I didn't have, and also flicked the
little throttle return dashpot. A couple of bits looked far too integrated
with lengths of wire going to the computer, so I left those, but as there
is only two of them, and you can't see them from above, why worry?
Then it was time to yank the motor and gearbox out
again, clean and paint them before re-installing them for good (hopefully).
I used Epiglass PA-10 as primer and blue Hammerite for the block/gearbox
with black sump and detailing, which looks really good, but isn't all that
visible with the injection in place! As an aside, I have found that a relatively
light coloured engine makes niggly minor leaks easy to find.
The next step was the wiring. I guess I like making
things hard for myself, but I don't like the idea of running an EFI engine
without having a warning/diagnostic light. What this means is that you
must run it with all the sensors, particularly the speed sensor, or else
you get a warning light. The speed sensor does not affect the way the engine
goes, but I don't want an intermittent warning light from it, otherwise
I'll never know when I have a real problem! Fortunately I had the inductive
pickup from the old engine, so I just wired it in.
My main concern was the exhaust/Lambda/oxygen sensor.
I had run one in the old engine until it broke off against the body when
the engine shunted back (after the sump hit a big lump of tar seal at speed).
The engine ran fine without it so I never replaced it. I always ran the
old engine on unleaded, but was concerned that the new one had to be on
super 'cos of the compression ratio (lead poisons the sensor), and had
a four wire sensor vice the single wire of the old motor (the four wires
are for sensor, earth reference, and a heater circuit to get the unit responding
quicker). I was aware that some of the newer engines will give an error
if the exhaust sensor isn't in the loop, as a means of ensuring emissions
compliance, and I was concerned that Toyota had got a bit more worked up
about such things since 1983.
I figured it was time to get some advice, and made
the mistake of ringing around. I got replies as follows:
 |
You don't need one, |
 |
You do need one, |
 |
We can sell you a black
box that fools the engine, |
 |
so and so's black box doesn't
work, we spend a lot of time pulling them out of cars that people put them
in, |
 |
we have one that is lead
tolerant for $300, |
 |
uses an EA falcon - they're
lead tolerant, |
 |
no such thing as a lead
tolerant sensor, |
 |
use an aftermarket computer
and you won't have to worry, and the common reply |
 |
don't know mate, try (one
of the above people)! |
It was time again for plan B - get the sodding thing
going and stuff a meter up the exhaust. I had a contact that was willing
to let me have a play with some sensors that came from full race Cosworth
Escorts in the UK if I needed them. I found it unsettling that I couldn't
get a consensus of opinion. Yet again, a word to the wise - very few Fuel
Injection/Electronics experts know much about setting up the more obscure
projects. I guess the answer is to use an aftermarket computer, but I'm
not that rich and decided that to go that way only as a last resort.
The rest of the wiring was pretty straight forward,
however my freshly translated diagram had only the engine electronics on
it, so if a plug had 10 wires and only 2 went to the engine or computer,
it didn't tell you what the rest did! I already knew that I couldn't buy
or source a manual in English for the engine, but found that the Toyota
EFI system is a derivative of the Bosch system, and the 20 valve set up
is much the same as the system laid out in the 1987 4AGE and 1983 AE86
Levin manuals I do have. So, with a bit more head scratching (no wonder
my hair is falling out) I managed to sort it all out, which I thought was
pretty good going, even if I do say so myself.
I had managed to sell my old engine, loom, computer,
spare sump, photocopied manual, original Toyota subframe and mounts to
some guys for $750, which I thought was excellent as it was broken (I still
do not know what was wrong with it - either bearings or maybe a piston
- but it still went well) and I figured that fixing it would not increase
the amount I could sell it for any more than the cost of the parts, to
say nothing of my time.
Unfortunately, in selling the old motor I also sold
the circuit open relay. So what you say? Well, this relay shuts down the
fuel pump if you have no air flow into the engine, a situation that occurs
when you crash and stall the engine. This prevents that fractured fuel
line becoming an 80 PSI flame thrower. Knowing how I drive, my luck, and
the inputs to the computer from the relay, I figured it might be prudent
to have one.
The local Toyota wrecker sold me one for $25, which
I thought was pretty good as they cost about $60 new. Trouble was (of course)
that on closer inspection the relay was arranged differently internally
- the relay has two operating coils, and a resistor and capacitor were
in parallel on the opposite coil for the new engine EFI system. And (naturally)
it wasn't just a case of swapping the wires. I went back to the wrecker,
who didn't have any others in their drawer... But they did have an AE 101
front cut! (less engine). 20 minutes of digging around later (the wiring
diagrams are schematic only and don't tell you the physical location of
the bits) I found the relay and the plug, and swapped it, which was a bonus
as this relay was out of a 1994 car and costs $100 from Toyota (and you
can't buy the plug). (Note: You don’t need this relay if you wire in the
oil pressure cut out - you can slave the fuel pump off it.)
The next hurdle was the cooling system. Remember
me saying that the inlet/outlet were at the back of the head? Well, wasn't
this fun? The shortest route to the radiator was over the top of the exhaust
manifold, which I initially rejected for two reasons - the hoses would
look ugly and be damned difficult to mount clear of the exhaust, and would
run higher than the waterjacket and radiator, which seemed an awfully good
recipe for air locks and baked engines.
Which meant I had to run lines down and along the
spaceframe then back up to the radiator. So what's the problem? Simple.
Each run is 41/2 feet long. Measure it, it is deceptive. And
I don't have the space to weld in fixed tubes. If I was building from scratch
maybe, but not now. OK, I'll do it in flexible hose. Wrong! You cannot
buy radiator hose in more that one metre lengths. Which means you have
to use braided line - at about $80/metre. For 3 metres. Plus Fittings (four
in number, at about $25 each). Ouch! I thought about steam hose, which
is rated at 180 degrees Celsius and 150 PSI, but it looks ugly and is about
$50/metre anyway. Non toxic PVC is rated to 250 PSI, but only 60 degrees
Celsius.
All this looked pretty nasty until I spied a roll
of used PVC tube in the come in handy pile at work. This had potential.
I liberated a chunk, figuring that I could dummy up the installation and
that way not buy a millimetre more braided line than I had to. Additionally
it gave me the opportunity to fire the sucker up before I bought the proper
stuff. (Note: Graeme Bluett in Hamilton has put a 20 valve into his Fraser
and made rigid aluminium pipe that are connected to the engine to reduce
the legnth of flexible hose required.)
So, after much messing about, it was all wired up
and ready to go. I thought it would be wise to crank the motor without
the plugs in to get some oil pressure up, and I was concerned that I may
have made a mistake in wiring the computer, so I checked all the wiring
with the diagram, and checked it again. I was concerned that the plug for
the car side of the computer that Neil gave me bore no relation to the
diagram colour coding, but one of his employees advised me to take the
lid off the computer and check out what was written on the circuit board
adjacent the plug pin. This confirmed that the drawing was correct and
calmed my nerves considerably.
I also had the coil unhooked so that there weren't
any stray volts running around. Time for the big moment. I hooked up the
battery, and was rewarded with a pleasing absence of sparks, smoke or untoward
aromas. Then it was ignition time. Again, everything seemed OK, warning
lights came up. Start. And nothing! At all! The lights stayed the same,
a relay went click, and that was it. Hmmmm. Maybe it does need the computer
after all (there are some 'start' inputs into the computer). Tried again.
Still nothing. Hmmmm. Maybe it needs the coil as well. Nope, no change.
Oh well, at least the computer hasn't gone fizz...
Time to check the starter motor, which I had rebuilt,
and previously tested. The terminals were shiny. Out with the multi meter.
No volts at the solenoid. I traced the wire back to the start EFI solenoid
and found a wire stub I hadn't hooked up, and had overlooked because it
was tangled up amongst a bunch of wires, and wasn't shown on the wiring
diagram. I hooked it up, and away it went. Once oil pressure was established,
I put the plugs in and started it. It ran first time, happily at idle,
as smooth as you could wish for, with all warning lights out.
Then it was time to top up the radiator fully. Fortunately
I had been warned by Fraser's that they were bloody difficult to get the
air locks out of the head, and after an hour of messing around and almost
cooking it a couple of times, got it sussed. There were two problems -
I had the hoses hooked up to the wrong end of the radiator, and the thermostat
was stuffed. So, I sorted that out, and managed to burp the air out. As
it turned out, having the clear hoses in enabled the engine to be checked
clear of air and for good flow.
Next step was test drive, as I wanted to be sure
it all ran OK before I formalised the wiring loom. And I needed a car fix,
it had been too long. So, with a chase car in case of glitches, we headed
off, with crash helmets on (to alleviate the hazards of bug strike), as
the car had no nosecone, scuttle, bonnet, windscreen, lights, mirrors,
mudguards, etc, etc. The only taillight, other than numberplate, was the
high stop light taped to the roll bar. Being law abiding citizens we were
driving on 'private roads'. Yes. Well, what can I say? We put about 100
miles on it (on PVC radiator hoses) at speeds up to 100 mph (I had some
shoddy tyres on that weren't really safe to go faster on), and cruising
at slow speeds, and it went great. No warning lights, grey exhaust and
oh what a beautiful engine.
It doesn't feel that much more powerful than the
old motor because it is so smooth, but given the amount of oversteer and
wheel spinning I'm getting, it certainly appears to be delivering the goods!
I removed the exhaust sensor wires, but kept them
incase things change in the future and we get high octane unleaded, although
it certainly runs OK without it. I've yet to get the exhaust analysed,
but it does appear to be fine.
The cars first outing in anger was at the end of
year motokhana at Botha Road in Penrose. The car was mostly complete, except
for proper radiator hoses and a few minor things. The day went well until
a relay played up and the radiator fan didn't cut in. The temperature gauge
was steadily climbing but wasn't too bad so we thought we'd do one more
run and then sort it out. We did the run and stopped the car with the gauge
on three quarters, which is where it runs if you give it death on a hot
day, and as the ignition was turned off the PVC hose burst with an attention
grabbing bang!
I was then subjected to a dozen knowing looks of
'should have known better', which I guess I deserved, however the truth
of the matter is that the car ran a total of 1200 miles on the PVC and
they only blew once (which is enough) due to the fan not working. Whilst
I certainly would not advocate the use of PVC as radiator hose material,
it does provide a cheap means of dummying up an installation. I found it
invaluable, as it enabled me to end up with the inlet to the engine being
1.5 metres of braided line running along the bottom of the spaceframe and
up to the inlet, with the return being via a length of stainless exhaust
tube above the exhaust manifold with braided line to connect it to the
radiator and engine. All up I needed six feet of braided line, and six
clamps.
The next step will be plumbing in the oil cooler
I bought, lack of space and money delayed me initially, and following a
minor collision when I was backed into, I will install it when I repair
the damage once the insurance claim is settled, but that is another story.
My engine lives on a strict diet of Mobil 1, and
has a thermostatic electric fan to keep it cool. The fan no longer whines
like a jet engine because the collision broke it, and the interim replacement
is considerably quieter. Additionally I have a 7 PSI oil warning light
that is hooked into the ignition circuit, so that the motor will not fire
until the oil pressure is up and the warning light goes off. This also
works in reverse so that if the engine loses oil pressure, it shuts down
at 7 PSI. Hopefully with the above measures I have eliminated start up
wear, and fully protected the engine. Time will tell.
Since getting the car running in late November 1994,
I took it down the South Island over Christmas, and have now clocked up
70,000 km on the 20 Valve. I had a wee fire just prior to heading down
South. My pressure gauge line was PVC, same as the old engine had, rated
to 600 PSI. It ran about three inches away from the exhaust manifold, but
could not get any closer, which I thought would be fine, but was (yet again)
wrong! One day I got a whiff of smoke out of the bonnet, noticed the oil
pressure gauge was on zero, and so killed the ignition before popping the
bonnet, when I found that oil had sprayed onto the exhaust manifold and
created flames about a foot high.
I had visions of my car burning to the ground four
days before driving down South, and was about to beat them out with my
T-shirt when they went out of their own accord. Apart from soot on the
bonnet, there was no damage, however I received a fire extinguisher for
Christmas, which was one of those things I'd never quite got around to
buying...
I bought a new T-piece that leads the line away from
the manifold, and the first foot of the line is now copper, as an added
safety feature. I had resisted copper at first, as I was concerned about
it work hardening and fracturing, but figure PVC bursting is more of a
worry. Incidentally the compression olives for copper and PVC tube are
different - the copper ones are barrel shaped whilst the PVC ones have
a collar to prevent them being compressed too much and cutting the tube.
Installing the thermostat was a cause for concern
until I cleared the forest for the trees. To cut a longer story short,
I installed the thermostat, which resides horizontally in the back of the
head, whilst I had the garden hose in the radiator, ensuring a constant
flow of water out of both sides of the thermostat until it nipped up. In
this manner, all the air was expelled from the engine. Additionally I have
a gradual slope from the engine outlet to the radiator, which relieves
all air from the engine side of the thermostat. (The conceivable problem
is air locking the inlet side of the thermostat.)
The temperature gauge sender, again a Triumph 2500
PI one, to match my gauge, screwed straight in to the Toyota mount. The
problem is that the sender is on the radiator side of the thermostat, so
it measures the cooled return water from the radiator rather than the engine
water jacket temperature. The hose between the radiator and the inlet to
the thermostat alone holds over a litre of water, not counting a heavy
duty modified Cortina radiator, the return hose and overflow tank, which
means that there is a hell of a lot of water to warm up before the gauge
reads anything. Typically this takes over 10 minutes of driving to achieve.
I thought of mounting the sender on the engine side of the thermostat like
Escort motors are, but I am going to run an oil temperature gauge on the
inlet side of the oil cooler, which will give me a quicker indication of
engine temperature.
In the final analysis I'm very happy with the engine
so far, although bolting the engine into the car was the easy part! I consider
that I had effectively no teething problems and have been most impressed
with the engine. The most surprising factor is that it is considerably
more economical than the old engine - I drove from Tawa in Wellington to
Pokeno in the Bombay Hills on $45 of petrol. This was on a trip that took
8 hours from Tawa to Glenfield, with a few brief stops along the way, and
no holds barred when overtaking, on a 4.44 diff ratio. I reckon that's
pretty reasonable.
Sure, it would be nice to have a 3SGE with even more
horsepower and torque, but where do you draw the line? As I said in my
original article about installing the 4AGE - my car is not a race car,
is my only transport and is used every day. It was a bloody good road car
with 118 horsepower, and with 165 it is realistically bordering on having
too much power now, but it would appear to be the ideal solution for me,
and I guess that is the important part - it doesn't matter what engine
or drive train you choose to put in your car - if it works well and does
what you want it to, then it is the right combination.
Once again my thanks to all the people mentioned
in this article, and the many others not, for their time and advice.
| THE BOTTOM
LINE - New Bits |
|
| Engine |
$2500.00
|
| Sump Shortening
and Bash Plate |
$ 168.75
|
| Oil Cooler/Adapter
Plate |
$ 281.25
|
| Fan Belt |
$ 18.00
|
| Paint |
$ 90.55
|
| Coil Lead
Cap |
$ 3.45
|
| Thermostat |
$ 28.70
|
| Temperature
Gauge Sender (Triumph 2500 PI) |
$ 14.00
|
| 7 PSI Oil
Pressure Warning Light Sender |
$ 20.00
|
| Accelerator
Cable Bits |
$ 19.00
|
| Air Filter |
$ 122.63
|
| Crankshaft
Spigot Bearing |
$ 6.05
|
| Braided Fuel
Lines/Vacuum line |
$ 226.62
|
| Electrical
Fittings, Wire, Conduit |
$ 65.55
|
| Oil Filter |
$ 15.87
|
| Sump Sealant |
$ 7.06
|
| Exhaust Manifold
Sealant |
$ 3.83
|
| Exhaust Gaskets |
$ 20.72
|
| Radiator Flush |
$ 8.79
|
| Stainless
Steel Nuts and Bolts |
$ 25.00
|
| Circuit Open
relay |
$ 28.12
|
| Braided Radiator
Hose and Clamps |
$ 300.00
|
| Stainless
Radiator Tube |
$ 35.00
|
| Oil Cooler
Hose and Fittings |
$ 227.00
|
| Oil Gauge
T-piece and line |
$ 30.00
|
| TOTAL |
$4188.94
|
| Bits I already Had: |
| Engine Mounts |
| High Pressure Fuel Pump |
| Gearbox |
| Alternator Bracket |
| Clutch Flex Plate |
| Fuel Filter |
| 4AGE Engine Manual |
| AE 86 Corolla Body Manual |
| Drive Shaft |
| Starter Motor |
| Compatible Gauges and Senders |
Note: The 20 valve now has some 42,000 miles on it
in my car, and despite running a 4.44 diff ratio returns a genuine 34.5
mpg regardless of around town or on a trip. The car will do 115 mph on
the flat before the speed sensor speed limits it, although it is still
accelerating. It will accelerate to 110 mph up long hills... I believe
it will do a genuine 120 on the flat in full road trim, clamshell, windscreen
etc, but it is largely academic as I want to keep my licence. Not bad for
a car with a cd of 0.74...
|