dynoed today. lost power since last time wtf

[crdcz03]

both were on mustang dynos. last time around septemberish 2005 i dynoed 181whp and 158wtq. they tuned it and all that fun stuff and that was the final numbers
since then i havent done much, just an h22 tranny, Quaife LSD, and carsound catalytic converter. i figured id put down like 2whp more lol

not the case... today i went to a local shops (different from the first shop)kinda "grand opening" ish dyno day. $20 for 2 pulls so i figured id go for the hell of it. sadly i only put down 169whp and 137wtq on the first run and 170whp and 139wtq on the second run.

so my question is... what causes such a drop? i know different dynos put out different numbers but they're both mustang dynos so id assume they'd at least be relatively close to each other. and it was a tad warmer today than when i dynoed back in september (was almost night time). but i cant see losing 20lb/ft over those two things

i have the sheets but no camera or scanner unless you include my camera phone but i dont know how well that would do. and besides, the sheet from a few months ago and the sheet from today are totally different looking so it would be sorta hard to compare the two.


if my car hadnt just been hit and run two days ago id be buying parts for the head right now

[danmakG60]

I would do a compression check and get a wideband too

[EK4me]

i wouldnt bother running the compression check. its probably the dyno difference and the lsd you installed

[EK4me]

oops sorry , i didnt read the whole post, disregard my reply

[bonestock94]

was last yrs dyno pulls done on a dyna pack or dynojet dyno? they read higher than mustang dynos.

[ATISTANG]

Theres a lot of factors that can cause that to happen. You are on two differn't dyno's, two differn't locations, two differn't seasons. There is altitude, barametric pressure, temperature, humidity, dyno calibration differences, if you are using a piggy back to tune it is poissible your ecm adjusted a few things over time to act better with your driving habbits. And I can't figure out how a lsd is going to make you lose hp, a few hp could have been lost throught the tranny if its made of heavier componets, or the gearing difference could also show a small hp difference.

[crdcz03]

Originally Posted by bonestock94

was last yrs dyno pulls done on a dyna pack or dynojet dyno? they read higher than mustang dynos.

the very first sentence would answer your question... this is illiteracy to a whole new level

[LilGecko96]

ive read that you can take your car to two diffrent shops with the same dyno and there could be like as much as a 10 - 15 hp diffrance, like ATISTANG said there are many veriables

[Hardedge]

Your losses seem pretty reasonable. You've got temperature difference, dyno difference, a different transmission, a new differential, and a different catalytic converter. If I did all that I would expect a serious power loss. And did the guys running the dyno the first time use a smoothing algorithm?

[f22hafler]

Originally Posted by Hardedge

Your losses seem pretty reasonable. You've got temperature difference, dyno difference, a different transmission, a new differential, and a different catalytic converter. If I did all that I would expect a serious power loss. And did the guys running the dyno the first time use a smoothing algorithm?

YES

[tienlude]

what ATISTANG said, should be common knowledge....+1

[9400rpms]

your comparing apples to oranges.

doesn't matter if its two of the SAME mustang dyno's.
Day,time month, year all that weather shit is different. Whats funny is, stock h22's put down mid 150~160'swhp on a dynojet, i wouldn't except bigger numbers from a low reading dyno in the first place.

[kommon_sense]

You guys realize this thread is a year and a half old right?

[G2IntegraGS-R]

Thats f22hafler's nub ass bringing it back to say "Yes"