I dynoed my car today, and the ambient temperature inside the dyno booth was 95*. My car made only made 470 rwhp and 445-ish rwtq with a 2.76" upper and a Steggy stage IV port. Do these numbers seem right considering the heat? It was tuned by Ed from RWTD...perfect 11.8-11.9 A/F and 23* timing. The guy at the dyno started pulling up other graphs where cars similar to mine had lost 30-40 hp by dynoing in different weather.
Lost HP due to heat
- Thread starter TheJeanyus
- Start date
Ed tuned mine & a couple buddies car in the heat. mmustangsrus' car only made 474 with a Stage 4 in the heat. Where did you dyno?
Walker Dyno Tune in Trussville, AL.lloyyd said:
Mine made 462/489 with no port. That's why I'm wondering about the low #'s.antiv6 said:
im sure you will lose some power due to heat. but with the correction factor of a dyno you shouldnt lose alot. try to get your car tuned when its the same temp out as the time before. i generally try to get my car tuned when its 70 out and low humidity.
It's not pinging or breaking up at all. Ed's tuned a lot of them, and as far as I know they're all still together. :shrug:posi said:
You can keep the tune I was just saying the norm on here seems to be what I posted. Me, I wouldn't have it that aggressive. But like I said it's your car and in the end you need to trust your tuner. My tuner shoots for the 11.5/21degrees of timing. Or even less on the timing if we aren't picking up any more hp/tq.
You can loose 30 hp due to heat. Don't believe me? Data log your Maf AD counts vs RPM on a hot day (90) versus a cool day (54). At the same RPM (5900) I saw the MAF AD counts be 990 (cool) vs 960 (hot). Our car's power are just really that sensitive to the heat outside. It sucks, but its a fact.
lloyyd said:
Josh has a Stage III ... and I think the temp on his sheet is above 100 degrees.Josh seems to be running good at the track as well.
TheJeanyus Do you have before and after track times?
Tune seems fine to me I ran the same est up for a year or two (23*,2.76,A/F),
How hot was it when you dynoed pre-port?
What did Ed have to say about it? Maybe he will chime in.
I have been to Walker in the past and my numbers were kinda high best I remember. I had a 2.76 no port 465 Rwhp 507RWTQ SAE. Two months later on Stiegemeiers dyno I hit 462rwhp 485 RWTQ STD Pre-port.
My car hit 445/502 after a good 30-45 minute cooldown with the IC pump jumped and flowing. On the 2nd run right after the first it only pulled 420/470, the first run got aborted due to a stuck throttle cable. That was on a 2.8 upper only, no port on a 90 degree day. Luckily for my 3rd run the guys at the dyno were cool and let the car sit a little longer than normal beforehand. They had no other cars after me.
If your car had been run a bunch of times on a 95-degree day then you were heatsoaked like a mofo and could have been down 30 hp to the tire. Given the heat I'd say that on a 65 degree day you'd be looking at a little over 500 rwhp 470-480rwtq. Do you have an off-road mid-pipe?
If your car had been run a bunch of times on a 95-degree day then you were heatsoaked like a mofo and could have been down 30 hp to the tire. Given the heat I'd say that on a 65 degree day you'd be looking at a little over 500 rwhp 470-480rwtq. Do you have an off-road mid-pipe?
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bring that car to a roadcourse with that 95degree heat for a 20 min session and you'll see your HP go down down down. I see it all the time with cobras.
Cobra drag strip=all business
Cobra road course on hot day=stay home
Cobra drag strip=all business
Cobra road course on hot day=stay home
I don't have any track times since the ported blower, and I never made a good pass before the port. My best was a 12.3 @ 117-ish, one of my friends ran a 11.99 @ 118 the same day with a 2.0 60'.
I'll head back to the dyno when it cools off and see what it does. Until then I'm just going to drive it and not worry too much about it.
I know I can feel a definite "butt dyno" difference in different weather, but I didn't know how much it would change the "SAE corrected" numbers on the dyno. I know the SAE correction factors are designed around N/A motors and blower cars react a lot worse to heat. Once the IAT's go up and the computer starts pulling timing, forget about making big numbers.
I'll head back to the dyno when it cools off and see what it does. Until then I'm just going to drive it and not worry too much about it.
I know I can feel a definite "butt dyno" difference in different weather, but I didn't know how much it would change the "SAE corrected" numbers on the dyno. I know the SAE correction factors are designed around N/A motors and blower cars react a lot worse to heat. Once the IAT's go up and the computer starts pulling timing, forget about making big numbers.
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dtheo said:
Humm I have more than a few buddys that open track their 03's year round with good results. I guess your of thinking way the Ford GT and Shelbys may need to stay off the open track too :shrug:
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