Cobra4B Posted June 21, 2010 Share Posted June 21, 2010 The 2002-2004 Z06 airbox lid has a larger hole on it than the 2001 Z06 and the 2002-2004 Z06 has 2 cats on the h-pipe vs. 4 on the 2001 (it has the 2 main cats, but 2 small pre-cats as well). Instead of having to hunt down an updated airbox lid and h-pipe and spend money would it be legal to simply enlarge the opening on my current air box lid and gut the 2 small pre-cats to effectively mimic the updated parts? It would save me a couple hundred bucks and not provide any extra performanc benefit over and above the OEM '02-'04 parts. -Brian Quote Link to comment Share on other sites More sharing options...
Trevor57 Posted June 21, 2010 Share Posted June 21, 2010 No. You are modifying parts, so you take points for it. Quote Link to comment Share on other sites More sharing options...
drivinhardz06 Posted June 21, 2010 Share Posted June 21, 2010 I *think* that GM actually changed the rear cats on the 02+ pipes to higher flow units than the 01. (would need to verify this). If so, there may still be an advantage to using the 02-04. I'd dyno your 01 first and get a good baseline, and go from there. You may have a good healthy one that doesn't need much massaging to get to what #'s you want Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted June 21, 2010 Author Share Posted June 21, 2010 Trevor yes I know it's a modified part by the letter of the law, but not in the spirit of the law. The end result would be the same w/o me having to waste money. Just wanted to see if this is something a NASA tt official could review on a case by case basis. Mark - Yes I've heard that too.... that the 2 main cats are more efficient, but looking at the h-pipe off of my vert and the 2003 Z06 h-pipe I put on it they sure look the same to me... I forgot to look at the number on the cat units themselves. Looking at that picture there's really no reason to waste money/time hunting down a 2002-2004 Z06 h-pipe when the spare I currently have (I have 2 actually) just needs those little pups cut out. I mean you can look at the bends etc. in the pipes and see that they're the same piece other than the 2 little pre-cats. Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted June 21, 2010 Author Share Posted June 21, 2010 Or I could reconsile myself to running R6s (6pt tires vs. 9pt) and ditch all the cats and weld in an x-pipe where the main cats were like I want to do anyway.... decisions. Problem is that if I did that and found that I need A6s to compete then I'd have to revert to the other h-pipe. Quote Link to comment Share on other sites More sharing options...
kbrew8991 Posted June 21, 2010 Share Posted June 21, 2010 Racing ain't cheap Neither is TT Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted June 21, 2010 Author Share Posted June 21, 2010 Yeah I know racin' ain't cheap, but I am.... and I have the things I have becuase of that quality Like I said, maybe I'll reconcile myself to running R6s and mod the car some more. R6s over A6s would allow me a proper CAI, UD pulley, and no cats. I'd do the cats more for the weight savings and the UD pulley (ATI superdamper) because it'll extend the PS pump life, dampen crank harmonics better, and free up a little power. If I decided to run A6s I could just throw the stock airbox back on and swap out to a stock h-pipe before the event. Quote Link to comment Share on other sites More sharing options...
Trevor57 Posted June 21, 2010 Share Posted June 21, 2010 There really isn't a way to prove that your mods are really going to be the exact same as the other oem stuff. Which is exactly why this rule exists. Exceptions to rules complicate things, and the enforcement of the rules needs to be easy, and consistent. Quote Link to comment Share on other sites More sharing options...
drivinhardz06 Posted June 21, 2010 Share Posted June 21, 2010 R6s over A6s would allow me a proper CAI, UD pulley, and no cats. I'd do the cats more for the weight savings and the UD pulley (ATI superdamper) because it'll extend the PS pump life, dampen crank harmonics better, and free up a little power. you're going to have to watch the hp with all that and a tune. ideally, get the car to min weight, use all the free mods, get the hp to where you want it WITHOUT using pts, use your points for the rest of the car. these cars really don't need any more hp, and if you do, you have to run them heavier, which is going backwards with the 275s Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted June 21, 2010 Author Share Posted June 21, 2010 At 3118 min comp weight with 275 tires it takes 370 rwhp to get to 8.42. A 2001 Z06 is going to have a hard time making that kind of power w/o LT headers especially one like I have w/ 119k miles. I figure a CAI, ATI superdamper, and cat delete w/ a tune would get the car in the 360ish range. Most 2001s make 335-340 bone stock on an accurate dyno. But you're right the thing to do would be to get it tuned w/ the UD pulley and the '02-'04 lid and h-pipe.... see what it makes then go from there. Running A6s and T1 bars a UD pulley is all I could do.... I'd be at 19. W/ R6s I could do the CAI and cat delete and still have 1 point left. Problem is that I used my connections to get a 2003 Z06 h-pipe for my vert a few months back... don't know of any others in the area cheap... will have to dig around. Quote Link to comment Share on other sites More sharing options...
drivinhardz06 Posted June 21, 2010 Share Posted June 21, 2010 Running A6s and T1 bars a UD pulley is all I could do.... I'd be at 19. W/ R6s I could do the CAI and cat delete and still have 1 point left. IMHO A6s and T1 bars > R6's and CAI/cat delete I will say a good ATI crank pulley is a very good spent 1+ mod if you go the A6/sway bar route, especially if you plan to twist it near 7k like a lot of these SE crazies Quote Link to comment Share on other sites More sharing options...
Cobra4B Posted June 21, 2010 Author Share Posted June 21, 2010 Yeah I had one on my yellow car... was a really nice piece, too bad they cost an arm and a leg. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.