alright, yesterday i got to throw my car on the dyno. my baseline run ended up being my best pass. no matter what i did, i lost power. advanced the intake cam, retarded the intake cam, advanced the exhaust cam, retarded the exhaust cam. bumped FP up, everything i did did not equal my baseline pass. even on the VAFC i couldnt make any differences. just curious if anyone has done that b4.

 

yeah that happened to me b4. had to dial in my cams due to thicker HG. best run was made when i had +4 intake, -1 exh (474 whp). started to play with more cam timing and ending up losing 15 whp. somehow couldn't get back the power. ended up with 464 whp. went home and realised that the cam gears was not lined up at exactly +4, -1, more like +4.5, -1.5. i guess these mistake were made trying to squeeze in as many runs within the hour.

 

Its called heatsoak

 

464 whp...gee- i bet you get AWSOME traction

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FULLTHROTTLE &raquo;</TD></TR><TR><TD CLASS="quote">Its called heatsoak </TD></TR></TABLE>

I'll agree on that one

 

yeah man , AWESOME Traction. Not!!! Today did a tune @ 25psi at the track with a Wideband. I am guessing it is over 500 whp. i will only know when i hit the dyno to do some fine tuning.

 

BoostedbyFastrax who tune your car and where located at i am not sure but i think you live in Md

 

did it with a D15B7...............

be surprised what 200+ passes at the drag strip will tell you about tuning...........



118 whp/135 crank hp from a puny D15B7 with easy bolt-ons.

Had a AEM CAI, tried a generic 3" short ram, lost power. Also had a B&M FPR. +/- 2 psi was lost power also!

Also note the the 6800 limiter, motor was BARELY still making power. I don't think it would have broke the 120 whp barrier though.

 

I went to the dyno on Thursday and had that problem. The temp there was 106 degrees. The car started losing power on every run. It was very frustrating. I made so many runs I did figure out what each adjustment would do so I adjusted the fuel and cam timing and now it feels much better. I left the dyno making .3 less hp but I know thats just from the heat.

 

well i guess im just happy to know im not the only one. i go there to expect to make/gain HP and torque and left with 3 less HP also. even looking at the graphs the changes i made didnt affect it much at all. so i guess ill go back to my backroads *** dynoing which seems to always have worked for me in the past.

 

newb question, but what is heat soak?

 

Yeah well done with the infamous *** dyno.

Sometimes you get the settings right before the dyno. Pisses you off cause you expect to pick up power with dyno time......

 

heatsoak is when ure car gets hot and just keeps suckin up hot air, as we all know colder air makes more power so u lose power on runs that ure car is too hot.

 

Best way to ensure that you maximize your dyno time is to monitor coolant and intake temps. Easy to do on an OBDII car, or if you have engine management (hondata, AEM, etc.).

If you don't have these options, a good coolant temp gauge and a multimeter work well. Monitor the intake air temp output with the multimeter.

Cool the car down between runs too. And if you turn the car off between runs, be sure to run it at 3000 rpm or so for 20 seconds before making your next run to cool the intake manifold (and IAT) down.

C_A_T

 

What about going to a Safeway and buying a couple bags of ice for the next time you take your car to the dyno? That way maybe if you cover the intake and IM you might have less of a problem with heatsoak.

 

better to learn proper cool down procedures.

Manual fan switch control along with proper use of the heater does wonders.

 

the temp wasnt very hot at all, manual fan switch was engaged when the car wasnt running, i was in the shade and the whole front end was off the car. cant do much more than that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by C_A_T &raquo;</TD></TR><TR><TD CLASS="quote">Best way to ensure that you maximize your dyno time is to monitor coolant and intake temps. Easy to do on an OBDII car, or if you have engine management (hondata, AEM, etc.).

If you don't have these options, a good coolant temp gauge and a multimeter work well. Monitor the intake air temp output with the multimeter.
</TD></TR></TABLE>

One of the local dyno shops here monitors the coolant temp using a laser thermometer gun. I believe it's a RayTek. When I dyno'd he allowed adequate cooling time between runs to ensure consistency. He didn't "rush" getting in the runs. He noticed that my car was running "cooler" and more consistent than the other cars that dyno'd that day. BTW, he also uses a Dynapack.

 

TOO cool (below 170F) and the ECU will still be in cold start loop.