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Discussion Starter #1
I got my car dynoed last week and it only made 200whp & 217 lb ft of torque. My mods are: intake, 3" turbo back exhaust, mbc at 15 psi, ct20b. It's a gen2 motor.
The AFR's were off the charts rich after 3500 rpm. I know I need some tuning but I think it should make more power than that as it is. It holds boost pretty well, I think it might drop to 14 psi by redline.
Prior to the dyno I replaced the spark plugs, wires, dist cap & rotor, & fuel filter. And I also checked my ignition timing & checked for boost leaks.

The only other things I know to do are check my cam timing & do a compression test.
I checked my cam timing today and the marks on the cam gears are both off by 180 degrees. In other words, I have the crank pulley lined up with the mark as described in the BGB and the marks on the cam gears are at the bottom instead of the top.
The car runs pretty well so I'm thinking it's just the marks that are off by 180 degrees and not the actual cams.

If anyone can think of anything else I should check, let me know! Thanks!
Alex
 

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When was the last time you replaced your ignition components - Distributor cap, rotor, spark plug wires and spark plugs?
I heard this can help alot.

Jeff
 

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MR2climber said:
I got my car dynoed last week and it only made 200whp & 217 lb ft of torque. My mods are: intake, 3" turbo back exhaust, mbc at 15 psi, ct20b. It's a gen2 motor.
The AFR's were off the charts rich after 3500 rpm. I know I need some tuning but I think it should make more power than that as it is. It holds boost pretty well, I think it might drop to 14 psi by redline.
Prior to the dyno I replaced the spark plugs, wires, dist cap & rotor, & fuel filter. And I also checked my ignition timing & checked for boost leaks.

The only other things I know to do are check my cam timing & do a compression test.
I checked my cam timing today and the marks on the cam gears are both off by 180 degrees. In other words, I have the crank pulley lined up with the mark as described in the BGB and the marks on the cam gears are at the bottom instead of the top.
The car runs pretty well so I'm thinking it's just the marks that are off by 180 degrees and not the actual cams.

If anyone can think of anything else I should check, let me know! Thanks!
Alex
your hp numbers sound identical to a friend of mine who also had 20B at around 15psi.... turned out that the Greddy SP exhaust was severely limiting his power.
 

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try removing the exhaust completely and dynoing the car after changing ignition components and see if that helps, it's an old car, need new stuff
 

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Discussion Starter #5
lol as I said in my post I just replaced all the ignition components a couple of months ago. And the exhaust is fine. It's all 3" mandrel bent tubing with a magnaflow muffler.
 

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What kind of dyno did you test on? Different brands of dyno (and different operator set-ups) will give wildly different numbers.

As an example, the summer before last my Evo made either 272, 302 or 330 whp - all with the exact same tune and mods depending on which dyno I used. The lowest number was from a Mustang dyno, but it was the best for tuning the car. I now use that "low" dyno for all of my tuning. Since then I've added about 35 more "Mustang" whp.
 

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You have an issue. Since it's going rich there isn't much to be concerned about but it would still cause a lack in power. The optimal a/f ratio is around 11.5:1.

EDIT:Just saw where your timing was off. That could be the issue there. You should be up around 240 or so rwhp and the cam timing being off would cause the power loss and a rich a/f.
 

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I thought it was normal for the stock GenII ECU to put out well below a 10:1 AFR once you excede 12 PSI?

You also have a 3" DP, correct? And yes, you are a little down on power, but there doesnt seem to be any obvious reason for it :eek: .
 

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Discussion Starter #11 (Edited)
qwik_MR2_5sfte said:
You have an issue. Since it's going rich there isn't much to be concerned about but it would still cause a lack in power. The optimal a/f ratio is around 11.5:1.

EDIT:Just saw where your timing was off. That could be the issue there. You should be up around 240 or so rwhp and the cam timing being off would cause the power loss and a rich a/f.
lol so far you guys haven't told me anything I didn't know already. Yes it is very rich as I said. This is to be expected from running a stock ecu with no tuning. But I'm under the impression that the car should make considerably more power even though it's so rich.

The cam timing marks are off by 180 degrees. Clearly the cams themselves can't be off by that much. Should I remove the valve cover to be sure the cams are aligned correctly?

Yes I'm running a 3" Aussie DP.

For reference, here's a thread of someone with practically the same setup but running a little bit more boost making 245 whp:
http://www.mr2oc.com/showthread.php?t=53925

One other thing I should mention, I'm planning on getting an aftermarket intercooler, FPR, & SAFC. I just don't have any money at the moment.
 

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when i had my alltrac, the timing was off by a couple teeth and it ran like piss. what had happened was the belt had slipped on the crank timing pulley.

to be honest, i'm not sure how the car still feels decent with the cams supposedly being off by 180 degrees. isn't it about impossible to put the gears onto the cams wrong/upside down?

i'd say to do that...after i fixed the timing belt, i was good to go on the alltrac...haha...then i had problems with the turbo and headgasket. [sigh].
 

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Discussion Starter #14
I really don't want to take the valve cover off if I don't have to. So far just checking the damn timing has been a pain in the ass! Can someone tell me whether or not the car can run ok with the timing chain being off by a tooth or two? My car runs fine other than the low power. Thanks.
Alex
 

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well, letsee... if youre timing is off, youre power is going to be crappy, your gas milage will probably suffer, and you'll probably risk knock/detonation issues when the weather starts to get warmer, you are NOT running ideal conditions for your engine right now, is that really something you want to leave unchecked?
 

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Discussion Starter #16
Gas mileage has been normal and I doubt there is much risk of knocking with the amount of fuel the ecu is dumping in the cylinders.

Anyone with actual experience of their cam timing being off is welcome to chime in. :)
 

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MR2climber said:
Can someone tell me whether or not the car can run ok with the timing chain being off by a tooth or two? My car runs fine other than the low power. Thanks.
Alex
HaPpYfAcE said:
when i had my alltrac, the timing was off by a couple teeth and it ran like piss. what had happened was the belt had slipped on the crank timing pulley.
MR2climber said:
Anyone with actual experience of their cam timing being off is welcome to chime in. :)
i put my two cents in...i really think you need to suck it up and check the cam gears. it should be a belt...not a chain. until you do that and find something wrong, i don't think there's a lot more we can tell you. if that's not the problem, then tuning would be your only solution...you should be doing that anyway. try running stock boost and see if that makes a difference.

if you don't want to try out what you've found here, then continue driving your car at your own risk. or maybe just take it to a good mechanic rather than relying on our 'help.'

:toast
 

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Discussion Starter #18
Thanks for the help. My point is that your car ran like piss when the timing was off. Mine does not. It runs pretty well, nice and smooth. I will probably end up checking it, maybe I just wanted to bitch about it first. lol My next car won't be midengine! :p
 

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My timing was off, i had a ct20B @ 1.0bar on a 1993 JDM GT-S at the time, and it sucks, and it felt crappy as hell. I had it fixed. There's a real life experience situation that you can relate to = )
 

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Discussion Starter #20
Thanks. :) I think for now I'm going to leave it be. I'm not too motivated to work on my car at the moment. I'm too lazy, plus I've got school and other things going on.

I'll get an SAFC and get it tuned whenever I have money. If the power isn't adequate after that, then I'll go on another diagnosing spree.
Thanks for the help guys!
Alex
 
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