Cold Air intake on a GSport

[Armitage]

So has anyone had a good experience putting a Cold Air Intake on a Grand Sport?
I hear loads of contradictionary info from it makes zero difference, it makes a difference of +20Hp... to others who claim it only makes a difference on a dyno because the car was tested hot the first time and cool (after the swap)... for the second test.
The GM Performance Cold Air Intake says it makes no gains on a Grand Sport... and why would they get it wrong?
I've seen a number of people who liked the AFE one as it didn't require any hose rerouting and sounded killer.

 

[cdnrx1]

So has anyone had a good experience putting a Cold Air Intake on a Grand Sport?
I hear loads of contradictionary info from it makes zero difference, it makes a difference of +20Hp... to others who claim it only makes a difference on a dyno because the car was tested hot the first time and cool (after the swap)... for the second test.
The GM Performance Cold Air Intake says it makes no gains on a Grand Sport... and why would they get it wrong?
I've seen a number of people who liked the AFE one as it didn't require any hose rerouting and sounded killer.

A CAI, by itself, will produce little to no performance increase on a stock LT1 as GM has accurately stated.

The main reason for this is the fact that the air intake tube creates a bottleneck in the induction system. It's design and construction do not allow for significant improvements in either efficiency or flow with anything over and above the stock air box. But they do sound great.

A CAI may well allow for more air to flow but as it reaches the intake tube it is A) restricted as to it's volume due to the bore size of the intake tube and B) the air that does flow is quite turbulent due to the design and construction of the intake tube, casting marks, ridges, etc. That's why the bore of replacement intake tubes from LG or WEAPON-X, as an example, have been slightly enlarged, moderately reshaped and considerably smoothed. This allows for more air to flow and to do so more efficiently with less turbulence. By comparison, the air intake tube from the Z06 has a larger bore designed to handle the increased air requirements of the supercharged LT4. It's over-engineered enough that it can accommodate slightly more air flow thus allowing for a small performance improvement when adding a CAI. Again, as stated by GM.

The best way to realize more HP from a CAI on a stock LT1 is to combine it with an aftermarket intake tube and less restrictive exhaust components, ie: headers, x-pipe, cat delete etc. This combination will allow for improved intake and exhaust efficiency / flow and, in theory, produce more useable HP. Unfortunately, to get the most out of it, it will also require a "tune" which may void the warranty.

You're quite right is your comments regarding dyno testing. They can be marginally manipulated, in terms of set-up, ambient conditions and engine temperature to produce the most desirable results.

Just my .02 cents, I'm sure others will have different opinions.


Best regards
Ross

 

[Keith Tedford]

The only way that you will see the full benefit of a ram air intake would be with a before and after quarter mile test. Sitting still won't show the ram air benefits if any. Tallying up all the advertised numbers don't count for much. Our 400 hp 2005 MIGHT put down 330 hp at the rear wheels. Our COPO 427 425 hp Chevelle made a whole 260 hp at the rear wheels on a chassis dyno. I was some disappointed because I was supposed to be getting a killer car. The rings in 5 of the eight cylinders didn't seat so a ring job on the new car was in order. These cars were jetted lean for emissions and a very retarded advance curve. Getting those things sorted out made a big difference. Closed headers didn't seem to make any big difference. Our 2005 runs well just the way it is so I am not about to spend a whole lot of money and perhaps mess up a happy combination.

 

[LUVMYC7]

Very well said Ross.
I also replaced my CAI and didn't notice any difference at all.