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Evidently, stock is best. *dyno charts*


WJM
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JWX's new toy....a completely bone stock 1988 RX 3 Door. It is like it was delivered off the showroom floor. 100% stock intake system, boost control system, ECU, exhaust....all of it factory stock.

 

stock1988.jpg

 

Interesting....it was turning the boost up by its self up high...I would have run it out to 8k but JWX didnt want to....it looks like the power band reversed up there.

 

Now, vs Mine, 4 mins after pull #3 of JWX's new toy....

 

stockvsWJM.jpg

 

Suffice to say, I am not very happy at this point.....

 

Also, I am now set on the fact that the 1987~1989 ECU's are a ton more advanced than what we think they are......

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Yeah...but calculated 150hp/170tq at the crank? There's something a-miss...

 

We put a boost guage on it....held 7PSI until it got past 5000...then, as you see the peaks there, it boosted to 10 psi...back to 7...back to 10.....back to 7....by its self.

 

We also changed the timing around...ALOT...from 35 deg to 20...to 10...back to 35. No differences. Those charts will be posted soon.

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I dont understand how a stock car is making the power mine is....

 

his compression numbers were...

 

1-115

2-115

3-100

4-125

 

 

MINE are...

 

1-145

2-150

3-150

4-150

 

 

I dont understand it.

 

Both Kevin's and JWX's other 88 RX (was mine, and was pleiades and then deadbolt before that) dyno'd the same at around 75hp/90tq at the wheels with intakes on them...on dynojets.

 

:confused::confused::confused::confused::confused::confused::confused:

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Yes.

 

anyone have theorys?

 

I have a theory. If his intake is stock, stock timing, stock boost checked with gauge and stock exhaust with no excessive leaks....then he's making power by (Drumroll)

 

He has excessive carbon built up in one or more of his pistons. Excessive carbon buid up will raise cylinder temps and pressure and make more power than stock. However, this will push him closer to his detonation threshold once he begains to raise the boost. His compression is higher due to the extra carbon built up. That's my take on this. :drunk:

 

I'll take it a step further and say this may even be causing his dyno chart not to be that smooth up high. See how funky the lines are? This is the same thing your dyno (Will) was doing when you increase the boost in your past dyno charts. Detonation/Pinging/Knocking.....one of those. I dunno! Just a thought.

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I have a theory. If his intake is stock, stock timing, stock boost checked with gauge and stock exhaust with no excessive leaks....then he's making power by (Drumroll)

 

He has excessive carbon built up in one or more of his pistons. Excessive carbon buid up will raise cylinder temps and pressure and make more power than stock. However, this will push him closer to his detonation threshold once he begains to raise the boost. His compression is higher due to the extra carbon built up. That's my take on this. :drunk:

 

but the compression #'s show that *I* have more compression....and he was running "stock" boost....aka it was dead on 7 psi until the ECU went to 10 then 7...10, 7, 10, 7...after ~5200 RPM.

 

Either way, before the boost increase, it was still making as much power as mine w/out IC...and more TQ.

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Between 2500 and 3500, what was his air/fuel ratio like? Air fuel ratios in the 14 -15 to 1 range can make a spike like that. I'm surprised he was able to start dynoing at 1000rpm. ??

 

AFRs are pig rich. I know from other RX's. The stock exh is too small for our wideband to fit in it... :banghead:

 

You can start the run anytime you want. I choose the green pill at 1k. :D Sometimes at 1.5k....but for RXs i always try to start low to get a good chart.

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Those things have WILD cams in them. i still say that none of our "stock" race cars pulled as well as our '88 rx!! By stock i mean stock turbo, the only mods being K&N and Open Exhaust.

 

 

The thing would pull all the way to 8 grand without a problem.

 

The 88 computers are agressive. They will pull/add alot of timing, and will play with the boost alot. You will see that on a really cold day in the winter, they will only pull like 7 PSI, but on a hot day, they will pull like 12 PSI in an effort to keep the power the same no matter the conditions.

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FSM says it best..it is a learning system..it's constantly advancing timing and adjusting boost..Having taken appart an 88' ECU they are complex..what I find interesting is room for a second ROM chip..Unisia Jecs now a subsidiary of Hitachi was doing interesting things and still is from what wrx ECUs can do..many a rex driver has noticed their car getting faster over time..

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Honestly they switched over the computers from 87-88 I'm not sure about 89, but maybe the 88 computers are more aggressive then the others. or its the carbon build up thing, I don't think it got rung out that often.

or its just the "strong" one on the run of cars it was on.

and the cold thing, it was colder as I was driving back, it it was pulling harder than my car at 10PSI, and healthier comp numbers. same roads, same night.

no on the JDM engine thing. I am planning upon trying to find all the stock intake stuff, and putting it back on with a K/N drop in filter, hook the stock boost controler back up and hopefully get more dyno time and see.

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I'm kinda wondering if you guys aren't over-analyzing this a tad...

 

I'm assuming that you're talking about a 4-wheel dynojet. If that's the case, then one of the things the computer on the 'jet will try to take into account is the increased losses inherent in an 8 roller dyno. 4 rollers lose more than 2 rollers and 8 roller lose more than 4. This brings up the question of tires.

 

WJM, I have no doubt that your engine is probably making more power the JWX's. However, if his tires were able to hold on to the rollers better, then the dyno will show his car making more power. This could be due to a better compound, better tread or simply because is tires were slipping on the rollers less due to less power output from the engine. What I would do, to eliminate that question is run both cars on the SAME tires. THEN compare dyno charts.

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Here's a simple answer: You arent making as much power, over stock, as you thought. Your motor is making more power than JWX's; just not as much as you had hoped for. 138 torque is sweet; don't sweat it Will :)

 

Where did all your other dyno charts go? http://wjmrallyesport.com/dyno_charts/ is devoid of your old charts :(

 

cuz they were faked =x

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