Big Geek

iTrader: (2)

I just put a set of Pacesetter headers and Y-pipe on my car. To my dismay the Y-pipe hits the bottom of the car. While I can deal with the clanking until I can figure out a good way to deal with clearancing it without beating up either the Y-pipe or the floor of the car I am wondering about the PCM picking up the clanking as false knock. It only does it upon the launch and is gone within a second or two. I know that it is most likely caused by the torque of the motor pulling it over to one side. So I pose this question- Is the knock sensor sensative enough that it can or will pick up the Y-pipe smacking the floorpan as knock and compensate by pulling out timing? I know that with my Turbo Buicks the knock sensors as sensative enough that they will detect the downpipe hitting the chassis sometimes and pull timing out. Thank you in advance for any and all advice regarding this matter. Cheers !!!

Jim C.

P.S.- It doesn't appear to have affected my times as the car (2000 Firebird, auto, 3.42 gears, airlid, longtube headers, Y-pipe and most of the free mods. The car is also heavy as it is a t-top and I weigh 302-lbs) has trapped at 105.58 with an E.T. of 13.24, 2.08-60FT. on street tires.

LS1LT1

iTrader: (16)

Unfortunately, yes.
It's not definite that it will but the sensors certainly can (and have in other cars) pick up the banging as 'false knock'.

Ferocity02

iTrader: (60)

Well the Pacesetter y-pipe is a piece to say the least. I think a quick fix it to get some high temp heater hose and place it between the y-pipe and floor board, and secure it with a large hose clamp. Or let an exhaust shop deal with it.