The other day a good friend's wife passed. It was not unexpected, she had been sick for about a year and it was her time. Her husband had been attending to Her for the last year and has been out of the loop racing wise. Before She got sick My friend was very active in SCCA and IMRA. He and I were "a team". I build / work on the car and he would drive. For those that care I get tremendous pleasure seeing what some one else can do with a car that I build. I also really enjoy translating what information about the car I get from the driver to making the car better for the driver. Then there is always the question of do I need to adjust the car or the driver?
Anyways, For the last 15 years+ I have been doing the freshening of the motor in his IT prepared MR2. This basically requires re ringing the motor. I can actually do it in the car with very little problem. So now that his wife has passed he has implied that he would like to get back in the car and go racing. I am sure he really misses it. It has been almost 4 years since I did the last fleshing. These motors last between 20-30 hours of racing between freshening and about 200 before you have to do a complete rebuild.
I have always used stock Toyota parts but was wondering what are good sources for parts for these cars and is there any upgrades improvements while I am in there. Are there better rings? I have already upgraded to the turbo oil pump (stock part that supersedes all the NA oil pumps). Are there any new speed secrets that have come to light in the last couple years that will squeeze some more HP out of these motors (that comply to the IT rules)?
So who has the best deals on quality parts for the 4age these days? At a minimum I will need rings, and a head gasket set.
Interested as well as my 4AGE is 'getting there.'
not sure what rules you are following.... I'm planting in excess of 145hp @ the rear wheels in my 4AGE powered rwd Corolla... and it is also emissions compliant. Torque is in excess of 90#s (peak is 112)for nearly 4500 rpm, also measured @ the rear wheels. Oh, it is also running all stock internals - except cams, and wrist pins.
http://grassrootsmotorsports.com/reader-rides/2130/
headwork can go a loooong way with these engines.
Got part of the answer.
just to refresh your memory... this is 10.75 to 1 CR(attained w/10 to 1 pistons and cutting the head), with a 264 type camshaft. bluetop internals inside a redtop block and head with a "clip and flip" smallport intake
This is an epic build by the way all should read I am truly impressed!!!! GRM should condense this in to an article !!!
http://hachiroku.net/forums/showthread.php?t=16037
I am up to page 34
thanks for the compliments...
the thread above is mostly the car build, this thread is mostly the engine build http://www.hachiroku.net/forums/showthread.php?t=10947
In essence...
smallport head ported by Loynings. objective as large a torque gain as possible
(In a 4AGE hp is easy, torque is hard)
How we did it...
1) decked the block approximately .015"
2) cut the head about .038"
3) equalized the combustion chamber volume
4) ported head - most of the work on the exhaust side
5) 3 angle on the seats, full radius back cut on the valves
6) 3 rib internals except wrist pins are 24 grams lighter
7) full rotational balance
Yes this is efi, sequential injection with wasted spark ignition, so yes - running aftermarket management with maximum ignition currently @ 35 degrees
Cam timing is as prescribed by Web (their 577 grind)
Here is the ignition map
I am also very interested in the cam can you shed more light on that? Stock?
How much was the management system. And can you shed more light on the type/mfg? I would really be interested in looking at that as that is legal. I can also get rid of the AFM and go to MAF or better yet just use MAP. Unforchantly I can not add a CPS like you did so I would have to figure this out. I think the major issue I am having is with the intake. I have also decked the head as well. . . ..
I actually went and looked up the spec sheet on my motor and it is a 10.5 / 1.
I don't think I need those special pistons. .. . Just yet. HOWEVER I am wondering if the ones you have are in effect acting like a HEMI and improving the air flow into and out of the cylinder. They are probably creating a better squish and a better shaped combustion chamber pattern as well. I am betting that this difference is a fundamental engineering improvement on the 4age flat tops that I am running. I am going to have to re think this as I don't think I can make my current head work with those pistons. Mmmmmm Time to think about things here. Maybe new pistons and another head with less taken off the deck and the basic IT spec port and polish is a better option. Hmmm.
oldeskewltoy wrote:
not sure what rules you are following.... I'm planting in excess of 145hp @ the rear wheels in my 4AGE powered rwd Corolla... and it is also emissions compliant. Torque is in excess of 90#s (peak is 112)for nearly 4500 rpm, also measured @ the rear wheels. Oh, it is also running all stock internals - except cams, and wrist pins.
http://grassrootsmotorsports.com/reader-rides/2130/
headwork can go a loooong way with these engines.
Gotta think about where it's gonna run, tho. I haven't seen the SCCA rulebook in awhile, but back when I was running IT, you could only match the port & intake/exh manifolds, the limit for grinding was 1" into either side of the gasket. Dean, does your buddy wanna stay SCCA, or is he gonna pump up the engine and go elsewhere?
SCCA IT allows the replacement of the AFM and allows an aftermarket ECU. I am well aware of the head work limitations and obviously will stay with in those constraints. I am not sure about the pistons. They are an oe part but.. . . . Well you know. Considering that MR2's have seen there day and are now a mid pack car in IT I am not really to worried about it however once you start creeping to the front people do take notice and will protest.
I have actually looked at EP as a possible place to bump to. We started building an EP cars some years back but then life got in the way. I have heard that the MR2 is actually more competitive in EP. The problem is that every bump in class is a hit in the $$$$.
I guess I am really just looking for the best source for Toyota parts especially rings Are there any better mousetraps out there?
I always used Toyota rings in my old IT MR2, and I'm sure other options are out there, but my old engine builder always preferred those to the others. He's built and driven numerious runoffs winners, including building the motor in last year's SSC winner.
Wow, and I just want to get the timing right and stop that clicking noise.
A LOT can be gain with just a little... Are you allowed to do a valve job?? Blending the valve seats into the bowls, along with a 3 angle(on the seats) and radiused back cut valves should gain you a decent amount...
The biggest restriction would be in the exhaust ports. The IDEAL way would be to change the merge angle of the port by working the outer walls (smoother taper). and as always the port roof can use work as well.
Are you allowed to use a "newer" piston? The later style of 4AGE does have 10.3 to 1 CR, BUT it also uses massive rods. Would you be allowed to enlarge a stock connecting rods small end to accomodate a larger wrist pin? That way you use the earlier crank and rods(saving OVER a kilo) and still benefit from a good compression bump?
Are you sure you have cut your head too much? As I stated mine was cut about 1mm(.040"), and I've ported heads with cuts as deep as 1.5mm(nearly .060")
Unless it's changed in the past few years, the internals had to remain stock, as did the cams and the head. you could do a small amount of "clean up" around the ports, but nothing major. You are allowed to change the ECU, however this is not as big of a help to the MR2 as it is to others. One trick is to build the motor, get a few hours on it, pull the head, rebuild it again, and then reinstall. It's good for a couple of hp and you still remain legal. It's also not easy to get a cone air filter to give you a big hp increase. You have to be careful where you "aim" it to get any real benefit.
Basically, unless you start replacing internals it's hard to get more hp by legal means. You can optimize what's there, but don't expect big gains like the Hondas can get.
I can do a better valve job than what is in there at the moment. As for the head, Ya it is milled as much as it can be (I think). I took static compression on the car and came up with 10.5/1 Heads CC'd at 29cc's. Looking at it I am guessing that it has had at least.125" off of it. There is actually some legal issues with IT classification but like I said running mid pack things like this do not really matter. I did not do the mill work the car came with it.
I really like your idea of getting the higher comp pistons. Add in a properly machined head (that is legal) and combine it with opening up the intake (getting rid of the AFM would help out alot!!!!) and some further exhaust work may be the answer. BTW I contacted the Toyota dealer in Singapore about getting pistons and they say that they will not ship to the USA. How did you get your pistons?
Regarding rotating mass. Since this car is primarily used for enduro races of 4+ hours or more high RPM is not nearly as important. There for the need to be as careful about the mass of the pistons,rods and crank are not as important as if this was a car used in sprints.
So I think I have two plans.
Plan A
1. Just freshen the current motor up and look at the valves.
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Go MS using the DIY plug and play getting rid of the AFM
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Look at the exhaust side of things and see if there is any improvement to be had. I really have not looked at that carefully. I am using a TRD header to a Cherry bomb so that part is ok. Where I have to look at is the ports in the head.
Plan B
Take my spare running 84 motor
1. Go with either the pistons you have if possible or the newer ones and have the rods machine
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Mill the head so as to get to about 10.5 /1
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Head Work to the IT spec paying attention to your comments above.
With the engine management changes and option #2 I would be thrilled to see 130hp
My last dyno run I was at 109 at the rear wheels. Blue is the first run of the day as I had ser the car up by ear. The red is the 9th run it was after playing with the timing and tweeking a could things. My only concern is that it looks to be going lean between 5 & 6k. I am going to have to look at that.
It is intresting to note that one hour of dyno time netted 10 hp and 9 torques by just tweeking timing and things. I also noted that max performance is about 6500-6750. IT also smoothed things out alot. Not bad for the $$.
Man have I rambled on!!!
I'm not a big proponent of running illegal parts. All you do is create a difficult situation in getting the car classed correctly, at a correct weight, etc. I know there are a lot of illegal cars in IT, but they don't help matters any, instead just add a lot of expense to their owners. Instead of adding cams and pistons, maybe a good driving school might be in order.
I once met a guy that ran illegal cams in showroom stock, not sure how he got away with that one! 
racer dave 600 wrote:
I'm not a big proponent of running illegal parts. All you do is create a difficult situation in getting the car classed correctly, at a correct weight, etc. I know there are a lot of illegal cars in IT, but they don't help matters any, instead just add a lot of expense to their owners. Instead of adding cams and pistons, maybe a good driving school might be in order.
I once met a guy that ran illegal cams in showroom stock, not sure how he got away with that one!
I completely agree and to the point I am concerned about the amount taken off the current head. The porting etc is to IT spec as is the rest of the motor (I built it).
Using the later pistons is legal they are in the later large journal 4age's. There is a long standing debate about durability versus rotating mass.
What I am not sure about are the special 10.5 /1 ones. I have not read the rules about that but they are an OE part. Some how I doubt it. With the new changes to the rules allowing much more freedom with the engine management and the ability to open up the intake as compared to the stock AFM setup. I can actually see the reasoning behind the rule change it in effect makes all the older AFM cars able to gain a little parity with the newer cars
Why would you ever think that we would be building an illegal car?
The real issue is that the MR2 needs to be reclassified it is no match for the rest of he cars in ITA. But I dont think SCCA wants a 20+ year old car to be the class of any group. A honda of the same displacement and weight has 50-75 more HP. However this is an issue for another thread.
stock cams die @ 6600 rpm, and it sounds like your tuning bears that out.
29cc chamber is TINY.... stock uncut head is 36.25cc. My head is @ 33cc.
You could gain a bit by decking the block(I already said that) and you can gain a bit with running a 7AFE gasket (stock 4age = 1.2mm, stock 7afe = .7 net gain of almost 1/2 point)
There are 2 advantages of running the earlier cranks and rods... one is the common mass vs strength, but as long as you stay under 8500, the early/lighter parts are plenty stout. The other reason to run the smaller parts has nothing to do with mass... the smaller crank has a drag advantage - because the journals are 40mm, instead of 42mm, there is less drag @ the crank/rod connection.
Hmmm, can you run the smallport engine - bare block and head? It wasn't available for the AW11, but it was available for the AE92, and the Geo Prism. The head is quite a bit better on the intake side... and it will fit with no mods** needed to the intake(like mine did) because you are in essence running the engine the same way as it sits in the AE92. Add the smaller internals, bump static CR to about 10.5 to 10.75, and run the older cams (the older cams - pre 88 have 6 to 8 degrees more duration then the cams were in 88+)
** - you will need to run the intake manifold from the smallport - there is an adapter sold which can adapt the old to the new... but it isn't as large a gain as running the smallport intake
oldeskewltoy wrote:
29cc chamber is TINY.... stock uncut head is 36.25cc. My head is @ 33cc.
As you can see I dont think I can take any more off.
oldeskewltoy wrote:
You could gain a bit by decking the block(I already said that) and you can gain a bit with running a 7AFE gasket (stock 4age = 1.2mm, stock 7afe = .7 net gain of almost 1/2 point)
This however is one of those golden nuggets that are invaluable. Something I am looking for!!!! The real trick to building one of these motors is in the details. There is no magic bullet with a 4age. It is a bunch of little things that have to be put together just so to go from really good to great.
I need to chew on the rest of the info you spelled out there re the large and small port heads. I don't think that it will be legal in IT I am not sure about the cams either. I need to read up on the back dating rules.
It has been reclassed in ITB now, some help, but still not a front runner.
