False dyno reports from magnaflow

[RPIpower]

Originally Posted by shabby It was on my car, but i wasnt there. Westport is just a shop that has a dyno, they're not affiliated with the guys from Solo Performance. Here is the dyno with the two difference 3" catbacks

Wish you were here. I'd let you dyno the car yourself.

[perris]

elroy, I'd love to know if you ever did re dyno a car after you disconected the ecu for it to zero itself out

I'll tell you what though, there is a chance it has flash memory which means it wouln't loose anything unless the ecu were actually reset to factoriy specs

[shabby]

Originally Posted by RPIpower Wish you were here. I'd let you dyno the car yourself.

A first class round trip ticket might solve that problem

[JMHZ2401]

Originally Posted by perris time logs on auto transmission, done with a computer log like dashawk and you log from wot I don't think in any scenario with the mods you are gonna get bellow 5 seconds, yet without mods we get right to it is there even a best case scenario where a modded exhaust gxp logged in the 4's?

That still does not solve. Dyno is still best and safeest way. Still driver error can happen in a auto (yes much less than a Stick car).

[MTS]

Originally Posted by bones Those dyno sheets are from my car.Everybody seems to think that the stock motor puts out about 216 whp stock. So if mine dynoed at 217 whp with the 3 " magnaflow, what would your guess be without the exhaust?About 190??? The exhaust had been on the car for approx. 800 miles,so had plenty of learning time I expected a little more, got a little less. No big deal. Just trying to show that there was no 30 hp gains. If its there i sure cant feel it. Maybe twords fall i'll put the stock exhaust back on and go try it again,just to keep everyone honest

One can't assume their car is going to put out a certain number stock. It's possible your car makes less than average on the dyno you use, so you can't use this dyno sheet above as a fact that says all magnaflow systems produce only 6hp gains.

Also, if you're saying the gxp magnaflow (or your exhaust line) makes 20hp gains but then the ecu pulls back the power, you're then admitting that your point is without merit as you're admitting the ecu is the culprit as to why this vehicle reads only a 6hp gain after 800 miles of break in time.

If you ask why I personally feel this whole argument is bunk then it's because I know how it is to have someone with their own personal agenda knock your product without thoroughly/accurately representing all the facts. Not saying you have some agenda, but you get my point.

Take care,
Rob
MTS

[bones]

Originally Posted by MTS One can't assume their car is going to put out a certain number stock. It's possible your car makes less than average on the dyno you use, so you can't use this dyno sheet above as a fact that says all magnaflow systems produce only 6hp gains. Also, if you're saying the gxp magnaflow (or your exhaust line) makes 20hp gains but then the ecu pulls back the power, you're then admitting that your point is without merit as you're admitting the ecu is the culprit as to why this vehicle reads only a 6hp gain after 800 miles of break in time. If you ask why I personally feel this whole argument is bunk then it's because I know how it is to have someone with their own personal agenda knock your product without thoroughly/accurately representing all the facts. Not saying you have some agenda, but you get my point. Take care, Rob MTS

I really have no axe to grind here. I'm just john q public that bought an exhaust system and put it on. I'm not badmouthing it or anything like that, I should have dynoed it before i put it on but i didnt. After seeing some of the gains that other people reported,i expected to see something similer.It was just a guess on my part that the ecu has pulled the gains back from the exhaust. I dont know if it has or not. I dont know if anybody knows for sure if this is happening or not. I dynoed the car after i put on the exhaust and the results are above. I was basically looking for info as to why my numbers seemed low,thats all.no more no less.The reason Eloy posted my dyno sheets was that my scanner doesnt seem to work,so i faxed them to him and he posted them for me. No big conspiricy going on here. Hope i cleared this up. Thanks Mike

[Critterman]

I have no idea why I'm joining in this fray as I can only speak from N/A experience. I dyno'd my car stock, then after the ECU was tuned everything except the temp was the same. 2 HP gain. In addition I went to the track after both dynos and showed .8 second gain.

Caught flack about my numbers, the temperature difference and I must have learned to drive the car yatta-yatta. So I re-dyno'd the car on a day that was basically the same as the baseline dyno within a couple of degrees. Can't remember if there was any difference.

Put on a cold air and a catback gained HP lost torque. My dyno sheets and time slips are on putfile user name critterman.

This is not an argument you can win. Dyno runs aren't cheap, unless you own the shop!

[achieftain]

Just so as to clarify a bigger issue between dyno results is if successive runs are not performed on th esame machine or at least brand then the results are meaningless. I guarantee if you ran two back to back runs 5 minutes apart at the same location but on different brands of dynos you will get different results.

[RPIpower]

It really wouldnt matter what any one posted here. Its the same sad story each time. "Something is wrong with your car." "There is NO WAY its only this."

Guys, believe what you want to believe. Anyways, you are all welcomed to our product testing session.

http://www.skyroadster.com/forums/sh...ad.php?t=15700

I understand that there are variances with the cars. Some cars make more power stock than others and I can assure you that its NOT a 30whp difference. I just find it funny that anyone who has posted charts of massive gains all have dyno runs where the print outs were GIVEN to them, and its not them taking their cars to get dynoed. lol. But hey, if any of you want to come Thrusday, feel free to. I will personally show you how a dyno works, how it makes calculations, how you gain power with an exhaust, how you DONT make power with an exhaust, how you increase VE, etc. Its free. We just ask that you respect our facility and not trash the place.

[MTS]

Originally Posted by RPIpower It really wouldnt matter what any one posted here. Its the same sad story each time. "Something is wrong with your car." "There is NO WAY its only this."

As a dyno operator you of all people should know there are variances in vehicle output from the factory, atmosphere conditions, operating temperatures, etc. Could a slipping clutch cause issues? Sure... Is the jump back on the dyno chart above a slip in the clutch or a slip on the rollers; was it strapped down correctly? Who knows.

Besides, dyno charts are useless anyway... they give you a histogram to work with why you tune a car... and right now, nobody can tune a GXP effectively, so it's moot.

[RPIpower]

Originally Posted by MTS As a dyno operator you of all people should know there are variances in vehicle output from the factory, atmosphere conditions, operating temperatures, etc. Could a slipping clutch cause issues? Sure... Is the jump back on the dyno chart above a slip in the clutch or a slip on the rollers; was it strapped down correctly? Who knows. Besides, dyno charts are useless anyway... they give you a histogram to work with why you tune a car... and right now, nobody can tune a GXP effectively, so it's moot.

Who needs to tune when you can slap on an exhaust and intake and make 40whp?

[LatinVenom]

MTS, You just agreed with him, NO TUNE NO CLAIM.

[MTS]

Originally Posted by LatinVenom MTS, You just agreed with him, NO TUNE NO CLAIM.

Adding higher flowing exhaust WILL increase horsepower without a tune. Depending upon the application it can add a little or a lot (relatively) horsepower. If the ecu pulls timing or whatever after the fact because it calculates a high torque value, than so be it... Doesn't mean adding exhaust wont add power claimed. Just means the ecu is holding the potential of the ecu back. One can raise boost, and tune the car, to take full advantage of a higher flowing exhaust. I can garantee my car is making about 260rwhp right now with catback, downpipe and boost controlled 17psi.

[Jack B]

Originally Posted by Mallard Jack B - Those are HPTuners screen shots.

Thanks - that even makes less sense, since HP Tuners recently posted that they cannot find the key to unlocking the ECU.

[Jack B]

Originally Posted by perris ya and that's what I meant, this is much better then dyno and as I say, there is nobody logging below 5 seconds...how can anyone make a claim of gain if they can't get even one or two tenths of a second

If you want a true gauge, the 60 is not a good bench mark, there are too many variables. The true yardstick would be to have the same car run the quarter multiple times at the same ambient air temp and watch the mph, that is the true indicator of hp. The comparison made before and after mods would tell all. Basically that is how you tune at the strip, for mph, not ET.

I am going to the drag strip next week. I have all those no-value mods, most of these cars run about 98-99 stock, it will be interesting where the cars ends up at.