the truth about CAI's
 

I see there's alot of people on this forum that seem to think CAI's alter A/F ratio . After reading everyone's reply's about CAI's I wanted to see for myself if there was a difference in A/F between stock & CAI's , so I got a few friend's together for alittle testing last weekend . I have numerous datalog files including STFT , LTFT & actual A/F ratio w/ WB . Datalogged 5 diff. cars , 3 '01 & later GT's , 1 '99 Cobra & 1 '92 5.0 LX . We tested stock against BBK style (end's right after entering fender) & also the one's that after entering fender make another 90 degree turn down . We found no change in A/F ratio , in any of the 5 car's we tested . and yes , I know LTFT is closed loop which didn't need to be logged for this test .

yeah, I remember reading that some people thought it hurt the a/f. but there's only so much air that can enter the engine without forced induction so there's no way any cai can hurt a/f

not saying i dont believe you but what were the mods on the cars? i definitely had a problem with the mac cai on my car, i could not drive in any gear below 2000 rpms, you know how some cars can just barely creep in first at around 5 or 10mph? well i couldnt. my car would start bucking. i had to give it some gas and let off and coast if i ever had to go that slow. in 5th gear on the highway (before getting gears) i had to be going at least 60mph or the car would run like **** because i was below 2k rpms. but as soon as i changed the intake i had no problems at all. the car rode perfect.


that has no relevance, there's turbulence when the air goes through the meter so it ****s up the readings.

yeah , I should have named the title something else , I know it was only 5 car's & only 1 cobra & 5.0 , well it's not a 5.0 , it's been bored & stroked . the cobra has new engine w/ fr500 heads ported/polished/cams . My car was the least modified , the other 2 GT's had head work & cams also . It wasn't my intention for people to read my results and think they will have no problem , I should have made that clear in first post and named title something like "datalogging A/F w/ CAI's" . Out of all the posts I read I didn't see where anyone did any datalogging(I could have missed some thread's) and just wanted to test some car's to see what happened .

When I got my car dynoed, I have a BBK CAI, my tuner even told me that after the dyno it's possible that he'll want to take out the bend and just make it a straight shot because it WILL give a bad A/F signal. And I trust this guy. BTW my BBK was alright with the A/F, not everyone's will be bad, but it is known to happen.

i dont have any a/f results to post, but i know my car drove like crap before. once i modded the intake i've had no problems. it's interesting to see that none of those cars had any difference in a/f ratio but another thing to consider is how long they've had the cai on the car. if you put one on the car and drive around for a while the computer learns and tries to compensate for things like that. if you have a chance to dyno your car again try resetting the battery and running the dyno immediately before it can learn and adjust. that will give you a more accurate reading of what the cai is really doing to the a/f ratio.

the a/f ratio was a little different from car to car , gt's were just about the same. we did reset PCM before each logging .

I DID DEFINATELY have problems with the a/f ratio with the bend. This thread is BS. :icon_bs:

thats exactly what i said... i definitely had problems.

Same here.......My car is running way cleaner than it did before

So if you had trouble with your CAI, then what did you do to fix the problem, anyone with JLT have A/F problems?

They just take out the bend and mount the Maf directly after the Maf, making it a straight CAI, similar to the JLT RAI.

I've never heard of anyone having problems with the JLT's.