by Chinky420 » Tue Jul 10, 2007 1:28 pm
i attempted fabricating a custom cai for my gen 1...as you can note in my sig, i wasn't able to get the extension measurements right, so i had to settle for a sri instead. it's not that hard, but it is time consuming.
3" pipe is feasible, but the angling is going to be kinda tough (as far as making the extension go into the fender). 3" is what i used myself in my project.
you can order aluminized tubing from JC whitney (under the exhaust piping/shop section on their website). make sure you get the mandrel bent tubing though, otherwise you may as well not even try it, and just buy a system that's already been made/tested (recommendations to cpe, in that case), since the gain's will be little other than noise. for me, it took about a week of working on it (as far as cutting the pipe, cutting and jbwelding the MAF port, and drilling the holes for the crankcase vent, and other hoses).
as for my seat of the pants dyno is concerned...i can't tell if there really is a difference in performance (since i cleaned my throttle body for the 1st time while i had the air intake off), BUT after taking a road trip this weekend, i noticed that i was able to get ~400mi to my tank (hwy) rather than the usual ~340 mi (which calculates to about an extra 4 mpg).
i wouldn't recommend doing it the way that tacti did (no offense), but that's just cuz i'm not a fan of duct taping 'performance parts' together in order to get minimal gains
....if you decide to undertake this project, i recommend getting aluminized mandrel bent steel tubing, many can's of ceramic engine enamel, 3" couplers for PVC piping (which will have to be cut to fit), and a metal blade for a hacksaw/reciprocating saw.
oh, and if you want to save your old airbox stuff, then i also recommend getting a used airbox (for the MAF sensor mount) from a junkyard/salvage yard, since it's easiest to mount the MAF sensor into it's original bracket (which i hacksawed off of my OEM airbox, for conveinence sake).
the end result, an ~8" SRI with a 7" AFE cone on it. it's kinda ghetto (IMO), and i only used aluminum tape in one spot that can't be seen...if you really want to do the CAI, be prepared to either make mistakes, or make presice measurements (which is really hard, i found out). in order to fit the extension through the fender.
pm me if you have any questions about my process