Cold air Intake???
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
if you want to calculate the increase in cold air temps effect on hp... consider that every 10 degrees of cold dense air increases HP by 1.4 + - .2 .... these are calculation from dyno tests that are corrected for ambient temps.. So lets say you have a stock air box and under the hood the temp is 100 F. and the ambient temp is 70 F. now add a heat extracting hood and this lowers the underhood temp to 80 F.. you have gained about 3.0 HP, not really noticed in the seat of the pants.. now add a cold air box that allowes the ingested air to be 75 degrees. whether or not you used the throttle body by pass... the ingested air is not in there long enough to raise the temp... adding the cold air box will get you another .75 hp making the gain aprox 3.75 HP...
Now take the same stock air box on a 30 degree day the underhood temp is 90 F now add a heat extracting hood bringing the underhood temp to 80, then add a cold air box bringing the ingested air to 40 degrees.. you have now lowered the ingested air down 50 degrees.. yielding about 8 HP but the difference between summer and winter with an extracting hood and a cold air box could be 10 to 12 HP.. this is why the car feels so much healthier in cold weather.. the air being ingested in much denser so you get more air molicules to be burn with the fuel mixture. The same situation occurs whether you have a stock air box or not you can feel the difference in the seat of the pants.. Itsd much more dramatic with an extractor and a cold air box... I hope this makes sense.... take a stock car with 314 at the crankwith air temp at 70 F... add an extractor and a cold air box your going to get 318 at the crank... Same car in the winter uncorrected hp is 316 add a heat extracting hood and a cold air box you are going to see 326 to 328 at the crank.
Now take the same stock air box on a 30 degree day the underhood temp is 90 F now add a heat extracting hood bringing the underhood temp to 80, then add a cold air box bringing the ingested air to 40 degrees.. you have now lowered the ingested air down 50 degrees.. yielding about 8 HP but the difference between summer and winter with an extracting hood and a cold air box could be 10 to 12 HP.. this is why the car feels so much healthier in cold weather.. the air being ingested in much denser so you get more air molicules to be burn with the fuel mixture. The same situation occurs whether you have a stock air box or not you can feel the difference in the seat of the pants.. Itsd much more dramatic with an extractor and a cold air box... I hope this makes sense.... take a stock car with 314 at the crankwith air temp at 70 F... add an extractor and a cold air box your going to get 318 at the crank... Same car in the winter uncorrected hp is 316 add a heat extracting hood and a cold air box you are going to see 326 to 328 at the crank.
What really amazes me is that not one person paid attention to real scientific information.
Melting Slicks
Joined: Jun 2004
Posts: 2,453
Likes: 81
From: Fishin' Pole FL
Race Director
Joined: Dec 2000
Posts: 19,304
Likes: 85
From: San Diego CA
This why I installed a "Car Chip" OBD II data logger before and after my cold air mod (with my Halltech Stinger intake installed). I found that under slow-moving and stop&go driving, the difference in actual intake air temps was dramatic, 140F+ without the mod vs 104F with the mod. As an added bonus, engine bay temps descreased almost as dramatically - reducing the harmful effects of heat on degradation of belts, hoses, and circuit boards. Buying a heat-extraction hood would also decrease engine bay temps, but at a huge difference in cost.
Advanced
Joined: Jun 2009
Posts: 56
Likes: 0
Well, I finally finished up the CAI install on my '02 Z06. I must say that I was thoroughly disgusted at the finished state of the VaraRam when I opened the box. It looked like someone pieced together a handful of plastic bits, put a sticker on it, and sold it to someone who didn't know any better.
The installation went well and was fairly straight forward once I juggled around the rubber hose connections to make the system whole. The VaraRam looks pretty good under the hood in the end.
Since the CAI addition was in conjunction with replacement valve springs from Patriot Performance, I gave the car a bit of time before really testing for performance gains. I never got a Check Engine Light, which was a surprise to me. After 40-50 miles, I ripped into it and could not help but smile. I cannot believe the seat of the pants dyno has jumped this much. The car has new life and I am enjoying every second of it.
My recommendation is to install a VaraRam, but this is only based on experience with it and the stock Z06 airbox.
The installation went well and was fairly straight forward once I juggled around the rubber hose connections to make the system whole. The VaraRam looks pretty good under the hood in the end.
Since the CAI addition was in conjunction with replacement valve springs from Patriot Performance, I gave the car a bit of time before really testing for performance gains. I never got a Check Engine Light, which was a surprise to me. After 40-50 miles, I ripped into it and could not help but smile. I cannot believe the seat of the pants dyno has jumped this much. The car has new life and I am enjoying every second of it.
My recommendation is to install a VaraRam, but this is only based on experience with it and the stock Z06 airbox.
Last edited by chiefsr; Apr 19, 2010 at 02:31 PM.
