[Z06] HP Tuners scan proves factory CAI does work
03-10-2007, 08:34 PM
#1
Tech Contributor
Thread Starter
HP Tuners scan proves factory CAI does work
I don't frequent this section too much so sorry if this is a dupe.
Using HP Tuners I logged some drag strip runs with my buddy yesterday in his new (to him) Z06.
As many of you know HP tuners logs IAT. My buddy has a Halltech filter and factory CAI. The Z06 factory cold air induction had IAT at 150 in the staging lanes, and got down to 104 at about 80 mph and stayed there. So it does work. Ambient yesterday was about 84 at that time.
I have a Vararam on my C6. My scan showed IAT 93 in the lanes and got down to 84 (ambient) by 100 mph.
You Z06 guys have a ton of timing being pulled starting at 86 degrees just like us C6 guys (factory tune of course). Here's your table. Note that my buddy had 10 degrees being pulled at the start of his run, and still 6 degrees when his IAT got down to 104. That's why these C6's love cool weather and the Vararam so much. Of course a tune takes care of that problem too.
Using HP Tuners I logged some drag strip runs with my buddy yesterday in his new (to him) Z06.
As many of you know HP tuners logs IAT. My buddy has a Halltech filter and factory CAI. The Z06 factory cold air induction had IAT at 150 in the staging lanes, and got down to 104 at about 80 mph and stayed there. So it does work. Ambient yesterday was about 84 at that time.
I have a Vararam on my C6. My scan showed IAT 93 in the lanes and got down to 84 (ambient) by 100 mph.
You Z06 guys have a ton of timing being pulled starting at 86 degrees just like us C6 guys (factory tune of course). Here's your table. Note that my buddy had 10 degrees being pulled at the start of his run, and still 6 degrees when his IAT got down to 104. That's why these C6's love cool weather and the Vararam so much. Of course a tune takes care of that problem too.
03-10-2007, 08:49 PM
#2
Le Mans Master
I think Jim Hall's tune does away with that. It has not been that hot here yet. Jim, is this correct?
03-10-2007, 09:17 PM
#3
Melting Slicks
This is one of many timing countermeasures GM has placed into the stock tune. This is part of the reason why back to back dyno numbers can produce horsepower swings of 20+ hp.
Howard
Howard
03-10-2007, 09:26 PM
#4
Tech Contributor
Thread Starter
). I had my car dyno'd on a dyno dynamics dyno and I see you use one and like them from other threads. I've read about them and I can see why you would like them. I had my car dynoed on one. But nobody believes my graph below.
In your opinion, how does the dyno dynamics compare to the more standard Dynojet? Does it read higher or lower?
By the way you Z06 guys stop laughing. I'm in a standard C6 with only Vararam, ported intake, American Racing headers and 3:90 gears.
03-10-2007, 09:56 PM
#5
Melting Slicks
Joe,
After two years of tuning cars on the DD dyno we have determined that it reads 10-12% lower then a DJ. We have backed up this math countless times as we have access to a DJ as well. Because of this we have set the "fixed" correction factor to allow for this and haven't looked back. This correction factor has nothing to do with the corrections from conditions (ie. temp, humidity and baro). I tune more then GM cars which include the 03-04 Cobras and also the Vipers so we have had our share of stock power cars come in in which the industry knows there outputs to compare too. We bought this dyno over the competitions as its a "tuners" dyno. Smooth load control, injector pulse for rpm signal and very repeatable. Its not always about the number but where the number goes after it has been baselined!
From the look of your dyno sheet it looks like you lost your tach signal. Let your shop know that using injector pulse as opposed to the inductive pickup is far more accurate if he hasn't done so. A stable RPM signal is critical to accurate numbers since torque is a function of rpm!
Nice numbers by the way!
Howard
After two years of tuning cars on the DD dyno we have determined that it reads 10-12% lower then a DJ. We have backed up this math countless times as we have access to a DJ as well. Because of this we have set the "fixed" correction factor to allow for this and haven't looked back. This correction factor has nothing to do with the corrections from conditions (ie. temp, humidity and baro). I tune more then GM cars which include the 03-04 Cobras and also the Vipers so we have had our share of stock power cars come in in which the industry knows there outputs to compare too. We bought this dyno over the competitions as its a "tuners" dyno. Smooth load control, injector pulse for rpm signal and very repeatable. Its not always about the number but where the number goes after it has been baselined!
From the look of your dyno sheet it looks like you lost your tach signal. Let your shop know that using injector pulse as opposed to the inductive pickup is far more accurate if he hasn't done so. A stable RPM signal is critical to accurate numbers since torque is a function of rpm!
Nice numbers by the way!
Howard
03-10-2007, 10:19 PM
#6
Tech Contributor
Thread Starter
Joe,
After two years of tuning cars on the DD dyno we have determined that it reads 10-12% lower then a DJ. We have backed up this math countless times as we have access to a DJ as well. Because of this we have set the "fixed" correction factor to allow for this and haven't looked back. This correction factor has nothing to do with the corrections from conditions (ie. temp, humidity and baro). I tune more then GM cars which include the 03-04 Cobras and also the Vipers so we have had our share of stock power cars come in in which the industry knows there outputs to compare too. We bought this dyno over the competitions as its a "tuners" dyno. Smooth load control, injector pulse for rpm signal and very repeatable. Its not always about the number but where the number goes after it has been baselined!
From the look of your dyno sheet it looks like you lost your tach signal. Let your shop know that using injector pulse as opposed to the inductive pickup is far more accurate if he hasn't done so. A stable RPM signal is critical to accurate numbers since torque is a function of rpm!
Nice numbers by the way!
Howard
After two years of tuning cars on the DD dyno we have determined that it reads 10-12% lower then a DJ. We have backed up this math countless times as we have access to a DJ as well. Because of this we have set the "fixed" correction factor to allow for this and haven't looked back. This correction factor has nothing to do with the corrections from conditions (ie. temp, humidity and baro). I tune more then GM cars which include the 03-04 Cobras and also the Vipers so we have had our share of stock power cars come in in which the industry knows there outputs to compare too. We bought this dyno over the competitions as its a "tuners" dyno. Smooth load control, injector pulse for rpm signal and very repeatable. Its not always about the number but where the number goes after it has been baselined!
From the look of your dyno sheet it looks like you lost your tach signal. Let your shop know that using injector pulse as opposed to the inductive pickup is far more accurate if he hasn't done so. A stable RPM signal is critical to accurate numbers since torque is a function of rpm!
Nice numbers by the way!
Howard
I had heard similar accolades on these dynos from high end shops. So maybe I'd get 10% more on a DJ? Cool. 
Nobody will believe me anyway. But I can hold my own at the drag strip where it counts. I've actually tweaked my tune quite a bit from drag strip logging.He said he had trouble on my baseline run, I thought he said spinning on the dyno but maybe he said the lead came off. You'll note my power dropping like a rock over 5800. I had a rev limiter kicking in at 5800 despite the main rev limiter being 6700 in every gear. That is why I bought HP Tuners - Tuners has a table to adjust an acceleration based rev limiter that the LS2 has that the LS1 didn't. And LS2 edit didn't have this table at the time my car was tuned. I bought Tuners to adjust this table myself.
03-10-2007, 10:53 PM
#8
Tech Contributor
Thread Starter
There are a lot more things to a tune than just that though. You could alter the IAT's reading with a resistor but that's an old school way dating back to when we didn't have the sophisticated easy to use tools we now do at the consumer level like HP Tuners. You are better off giving your computer accurate information and then deciding what you want to do with the accurate info.
