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Marauderjack
08-25-2004, 10:17 AM
Hey Folks....

I have been running an SCT program and a PHP cold air box for a couple of months now and the sound.....as well as performance seems GREAT!!! :up:

Recently I was running about 45 MPH in 4th with TC locked and floored it to pass!! :cool5: Well....I discovered that lifting the accelerator about 1/4" gave me much more power than WOT??? :eek: Upon reapplying WOT it continued as expected!! :cool5:

Now.....My fear was that the TC was trying to engage at WOT or the Alternator was coming back on for some reason?? :nono: Further experimenting revealed that part throttle runs were the same way as long as it was from 3rd or 4th gear and a downshift?? (From a stand still WOT seemed to work OK...When I backed off so did the engine)!

Quite by mistake I found out that my combination DID NOT LIKE the "J" tube that I reinstalled to control intake noise with the PHP box!! :eek: I took out the SCT program and "Stock" works OK with the "J" tube?? :up:

I removed the "J" tube and reinstalled my plug and drove the car to Charlotte today and under all conditions it performs flawlessly....Much smoother and stronger than with the "J" tube......Sooooo if any of you have weird things happening by all means remove the "J" thing before you change a lot of stuff with respect to programming!! :soapbox:

Here endeth the epistle for the day!! :rolleyes:

Marauderjack :pimp:

RF Overlord
08-25-2004, 10:28 AM
Excellent detective work, Mr. jack... :up:

I'm curious as to WHY this should matter, though...the J-thingie is just a resonator for acoustic control...it should have no effect on air-flow... :confused:

Marauderjack
08-25-2004, 06:29 PM
RF....

I can't explain what the difference is but it is much better without the "J" thing!!! :party:

I wonder if it has to do with harmonic shock waves with the SCT program and no intake restrictions??? :dunno:

Marauderjack :D

Dr Caleb
08-26-2004, 08:20 AM
RF....
I wonder if it has to do with harmonic shock waves with the SCT program and no intake restrictions??? :dunno:


I was thinking on why last night. I expect the idea of the silencer is to keep air pressure from changing suddenly, thereby reducing the noise it makes and smoothing it out for the MAF.

Perhaps removing the silencer increases the throttle response, but also makes the air through the MAF more unstable? The programming perhaps can't deal with the faster responses of the air?

:confused: