[Z06] Big difference in power when the temp went up.
Thread Starter
Instructor
Joined: Mar 2005
Posts: 231
Likes: 1
Big difference in power when the temp went up.
I know hotter air makes less power due to it's lower Oxygen content.
This engine seems to be affected even greater than others I've had in the past. The power difference between 45 and 75 degrees is large.
I have also noticed that when I shift near redline, that I get a quick loudish detonation as I hit the gas right after the shift. Just a single detonation, and the ECU quickly compensates for it. Is this normal for this car?
I recently installed the Vararam intake. At first, I thought I noticed a difference, but now I'm not so sure... Isn't this intake supposed to be the best?
Anyway, I'm going for a ride
This engine seems to be affected even greater than others I've had in the past. The power difference between 45 and 75 degrees is large.
I have also noticed that when I shift near redline, that I get a quick loudish detonation as I hit the gas right after the shift. Just a single detonation, and the ECU quickly compensates for it. Is this normal for this car?
I recently installed the Vararam intake. At first, I thought I noticed a difference, but now I'm not so sure... Isn't this intake supposed to be the best?
Anyway, I'm going for a ride
Melting Slicks
Joined: Jul 2003
Posts: 2,454
Likes: 0
From: Ventura County CA
Originally Posted by Innovator
I know hotter air makes less power due to it's lower Oxygen content.
This engine seems to be affected even greater than others I've had in the past. The power difference between 45 and 75 degrees is large.
I have also noticed that when I shift near redline, that I get a quick loudish detonation as I hit the gas right after the shift. Just a single detonation, and the ECU quickly compensates for it. Is this normal for this car?
I recently installed the Vararam intake. At first, I thought I noticed a difference, but now I'm not so sure... Isn't this intake supposed to be the best?
Anyway, I'm going for a ride
This engine seems to be affected even greater than others I've had in the past. The power difference between 45 and 75 degrees is large.
I have also noticed that when I shift near redline, that I get a quick loudish detonation as I hit the gas right after the shift. Just a single detonation, and the ECU quickly compensates for it. Is this normal for this car?
I recently installed the Vararam intake. At first, I thought I noticed a difference, but now I'm not so sure... Isn't this intake supposed to be the best?
Anyway, I'm going for a ride
Team Owner
Joined: Mar 2001
Posts: 25,889
Likes: 7
From: Virginia Beach
CI 3-5-6-7-8 Veteran
All cars loose some power in hotter temps, but to me this car still feels fast in the hottest weather whereas my '97 Cobra felt like a complete slug when the temps came up. I dont' have any detonation problems, not sure why you would... do you live on the west coast and have to use lower octane gas?
Melting Slicks
Joined: Sep 2003
Posts: 2,458
Likes: 105
From: Northville Michigan
Richard,
Get yourself a Tune ASAP. With the VaraRam you are able to flow much more air than with the stock air cleaner. Your engine's PCM is not able to increase the fuel flow enough to compensate for the increased airflow. You will probably find your air-fuel ratios in the 14.0 to 14.5:1 range.
If that is the case it will cause the detonation. You need to get your air-fuel ratios back in the 13.0 range. 
I just went through the same thing in my Z06. I picked up 30 RWHP by correcting the air-fuel ratios.
.
Get yourself a Tune ASAP. With the VaraRam you are able to flow much more air than with the stock air cleaner. Your engine's PCM is not able to increase the fuel flow enough to compensate for the increased airflow. You will probably find your air-fuel ratios in the 14.0 to 14.5:1 range.
If that is the case it will cause the detonation. You need to get your air-fuel ratios back in the 13.0 range. I just went through the same thing in my Z06. I picked up 30 RWHP by correcting the air-fuel ratios.
.
Last edited by Pumba; May 15, 2005 at 09:26 PM.
Thread Starter
Instructor
Joined: Mar 2005
Posts: 231
Likes: 1
Originally Posted by Pumba
Richard,
Get yourself a Tune ASAP. With the VaraRam you are able to flow much more air than with the stock air cleaner. Your engine's PCM is not able to increase the fuel flow enough to compensate for the increased airflow. You will probably find your air-fuel ratios in the 14.0 to 14.5:1 range. If that is the case it will cause the detonation. You need to get your air-fuel ratios back in the 13.0 range.
I just went through the same thing in my Z06. I picked up 30 RWHP by correcting the air-fuel ratios.
.
Get yourself a Tune ASAP. With the VaraRam you are able to flow much more air than with the stock air cleaner. Your engine's PCM is not able to increase the fuel flow enough to compensate for the increased airflow. You will probably find your air-fuel ratios in the 14.0 to 14.5:1 range.
If that is the case it will cause the detonation. You need to get your air-fuel ratios back in the 13.0 range. I just went through the same thing in my Z06. I picked up 30 RWHP by correcting the air-fuel ratios.
.
Melting Slicks
Joined: Jul 2003
Posts: 2,454
Likes: 0
From: Ventura County CA
Originally Posted by Innovator
Thank you for your advise. Although I HIGHLY doubt there is that much more air flow through the Vararam filter than with the stocker.
Thread Starter
Instructor
Joined: Mar 2005
Posts: 231
Likes: 1
Originally Posted by slong
To each his own. You now have a ram air system with the VR. Trust me you are getting much more air at speed. Now for the tune, I believe Innovator is correct, but the problem is hard to duplicate the VR performance when you’re at a stand still dyno run. Good tuner will compensate for this, so a local shop has told me about mine. Maybe you should go back to OEM air box. Good luck either way.
What has me a little concerned though, is that my car seems a little slower now, if anything...
Last edited by Innovator; May 17, 2005 at 09:11 AM.
Le Mans Master
Joined: Mar 2002
Posts: 6,885
Likes: 2
From: Corpus Christi TX
I keep reading this time and time again....a 13.0 or even a 12.0 a/f ratio guarantees nothing as far as detonation. A 12.0 a/f ratio can detonate if the other key tuning parameters aren't dialed in. You can even have audible detonation and not set the knock sensors off. It happens.
I will agree with the rest of the advice....seek a professional tuner that can handle all of the parameters and make adjustments accordingly.
I will agree with the rest of the advice....seek a professional tuner that can handle all of the parameters and make adjustments accordingly.
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Thread Starter
Instructor
Joined: Mar 2005
Posts: 231
Likes: 1
Originally Posted by Shylor
Well I'm not worried about it either but, it's nice to know there are benefits to warmer weather.
I installed the Magnaflow X pipe, and now the car sounds wimpy. Now the Vararam is making the car slower?
Le Mans Master
Joined: Dec 2000
Posts: 7,096
Likes: 153
From: "Atlanta" Ga.
Originally Posted by Pumba
Richard,
Get yourself a Tune ASAP. With the VaraRam you are able to flow much more air than with the stock air cleaner. Your engine's PCM is not able to increase the fuel flow enough to compensate for the increased airflow. You will probably find your air-fuel ratios in the 14.0 to 14.5:1 range. If that is the case it will cause the detonation. You need to get your air-fuel ratios back in the 13.0 range.
I just went through the same thing in my Z06. I picked up 30 RWHP by correcting the air-fuel ratios.
.
Get yourself a Tune ASAP. With the VaraRam you are able to flow much more air than with the stock air cleaner. Your engine's PCM is not able to increase the fuel flow enough to compensate for the increased airflow. You will probably find your air-fuel ratios in the 14.0 to 14.5:1 range.
If that is the case it will cause the detonation. You need to get your air-fuel ratios back in the 13.0 range. I just went through the same thing in my Z06. I picked up 30 RWHP by correcting the air-fuel ratios.
.
I have a Vararam and I noticed a diffrence at highway speeds
Thread Starter
Instructor
Joined: Mar 2005
Posts: 231
Likes: 1
Originally Posted by Gonzo
This is correct, your A/F ratio should be around 13 with the Vararam. If you doubt this call Vararam and speak to the owner. I did and he told me the A/f with the vararam is best around 13.
I have a Vararam and I noticed a diffrence at highway speeds
I have a Vararam and I noticed a diffrence at highway speeds