Bad Dyno Results
Thread Starter
TECH Enthusiast
Joined: Apr 2003
Posts: 732
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From: Las Vegas
Bad Dyno Results Well, finally got my car dynoed today, along with my friends corvette. My sig has my mods.
This was corrected to altitude and was at 84 degrees. The car was nicely warmed up.
rwhp 299.8
rwtq 318.3
The shop were I got most of my work done has said that these numbers are a little low and they would talk to the main computer programmer and check with him. I recently had things retuned for the 3.15 gears and the Z06 size tires, and when first driving the car it felt absolutely great, but a couple of minutes down the road, it felt like the power fell off. They guy checked my system and said that everything was allright that day, but the car has felt a little week to me since the retune!
My freinds vette has all the same mods except for no headers, and no torque converter, also he has a corsa cat back, but I don't think the cat back makes that much difference compared to a Z06 exhaust. He dynoed:
rwhp 313.3
rwtq 313.8
It was weird also cause my car sounded so much more meaner and powerfull than his.
Now we raced a couple of times after the dyno, and I jump a car length on him due to the bigger tires and torque converter, then the cars sit right in the same spot up to 100mph before letting off. My car was just a little warmer than his, but not much to make the difference.
I would like your guys opinion about what I should do or look at, and I would appreciate any comments!
This was corrected to altitude and was at 84 degrees. The car was nicely warmed up.
rwhp 299.8
rwtq 318.3
The shop were I got most of my work done has said that these numbers are a little low and they would talk to the main computer programmer and check with him. I recently had things retuned for the 3.15 gears and the Z06 size tires, and when first driving the car it felt absolutely great, but a couple of minutes down the road, it felt like the power fell off. They guy checked my system and said that everything was allright that day, but the car has felt a little week to me since the retune!
My freinds vette has all the same mods except for no headers, and no torque converter, also he has a corsa cat back, but I don't think the cat back makes that much difference compared to a Z06 exhaust. He dynoed:
rwhp 313.3
rwtq 313.8
It was weird also cause my car sounded so much more meaner and powerfull than his.
Now we raced a couple of times after the dyno, and I jump a car length on him due to the bigger tires and torque converter, then the cars sit right in the same spot up to 100mph before letting off. My car was just a little warmer than his, but not much to make the difference.
I would like your guys opinion about what I should do or look at, and I would appreciate any comments!
Staging Lane
Joined: Jun 2004
Posts: 73
Likes: 0
From: San Diego
Yea I think I would be dissapointed to...the 299 is corrected? With 3.15's with a tune stock you should be close to that with the 3.15's. The stall isnt too high... I dunno.. Anyone else care to chime in?
Staging Lane
Joined: Jul 2004
Posts: 72
Likes: 0
From: Alexandria, VA
Both were dyno'ed at the same shop on the same dyno, right? And I'm assuming your friend also has the 3.15 rear end.
OK, first off, some engines are just stronger than others. It just happens. They can come off the assembly line right behind each other and one will still be a little stronger than the other.
Next, you've done some drivetrain mods that your friend doesn't have. Bigger hole shot but maybe a little less on the rwhp.
Finally, you really haven't done any engine mods that produce noticably higher hp. The stock LS1 engine produces somewhere between 290 and 310 rwhp. Yours is pretty much right in the middle.
My 04 coupe has similar mods to yours (Vararam intake, Corsa exhaust, 2800 Vig TC, but with 3.42 rear diff) and I dyno'ed at numbers very similar to yours.
OK, first off, some engines are just stronger than others. It just happens. They can come off the assembly line right behind each other and one will still be a little stronger than the other.
Next, you've done some drivetrain mods that your friend doesn't have. Bigger hole shot but maybe a little less on the rwhp.
Finally, you really haven't done any engine mods that produce noticably higher hp. The stock LS1 engine produces somewhere between 290 and 310 rwhp. Yours is pretty much right in the middle.
My 04 coupe has similar mods to yours (Vararam intake, Corsa exhaust, 2800 Vig TC, but with 3.42 rear diff) and I dyno'ed at numbers very similar to yours.
Thread Starter
TECH Enthusiast
Joined: Apr 2003
Posts: 732
Likes: 0
From: Las Vegas
Stock cats with SLP h-pipe, he does have 3.15 auto also, run on same dyno same day! Well, maybe I just need to say screw it and get the heads and cam. I might do it a part at a time since it will take such a long time to come up with that money! I didn't know that others would have dynoed so close also, most dynoes listed are much higher than mine, making me think that something is wrong!
Staging Lane
Joined: Jul 2004
Posts: 72
Likes: 0
From: Alexandria, VA
Originally Posted by hodgeee
I didn't know that others would have dynoed so close also, most dynoes listed are much higher than mine, making me think that something is wrong!
Like a lot of folks say, dynoing is just for bragging rights. Take it to the track if you really want to see how fast it is.
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What your static test shows is you propably need tuning. The PCM needs about 20 minutes of a driving cycle to adjust to any changes and 30 seconds on a dyno will not give you a true picture. If you made 6 pulls in the same conditions, you would get 6 differect results. Find someone with a good scanning software, hook it up and give the car a good workout. You will need a couple of 80-140 mph romps in 4th gear. This will give you duty cycle of the injectors, LTFT,advance, etc. As stated before each engine is a little different and reacts to different inputs. In the Z06, the biggest problem of adding headers and breathing is injectors--many switched to the SVO 30 lbs.
Another suggestion is cold Intake Air Temperature. This creates HP.
Another suggestion is cold Intake Air Temperature. This creates HP.
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