Everytime I shift the car at high rpms (4,500 - 6,000 rpms), I get upto 9 degrees of timing being pulled out. The rpm varies and so does the ammount of timing pulled when this happens. Could this be problems in PE or just header knock being picked up by KS(longtubes pretty close to frame)???

It pulls upto 9 degrees out cause I set MAX timing retard to 9 degrees in the PROM.

ANy suggestions?

I use Datamaster to scan with and I can e-mail someone a .uni file or 2 if anyone would like.

Thanks!

Mike

 

You have to have the mechanical stuff right before tuning. Yes, an exhaust rattle can easily trigger the knock sensor.
As well as some cam profiles.
A bad serpentine belt.
Alternator bearings.
tracking down false knock can be a PITB

 

I have similar BS going on with my corvette right now and its ticking me off. In the dead middle of 1st gear at the track it pulls 8.4* out @ 4800 then slopes back to nothing. Then 4800 in 2nd and 3rd do the same thing, but less degrees. Car shows no feel of power loss, but its showing up in the scans. Pulled hte knock sensor connector and promptly gained 2 tenths back in the 330'.

Grrr...

 

i get the KC on starter engage and also on a shift. happens always on starter and once a day on shift(manual). 4+3 is kinda clunky on shift? i did see KC under load at 30-40 map 2400-2800 rpm so took out 2 deg (only there) timing and that definately helped. not totally sure is the knock was from spark table too aggressive or some mechanical noice. i am running 10 deg initial timing with stock spark table from 84 vette. would the stock timing curve would bring KC? maybe the 10 deg initial adv brought it on! using tuner cat/winaldl. i am hesitant toallow more advance anywhere for fear of more knock. what else brings on KC? headers are not touching and not loose.

 

I think what I'm gonna do first is make sure I'm not lean in PE and then I'm just gonna run 100 octane and disable the damn KS stuff in the .bin! Hell, carbed motors dont use them!

Or I will just set knock sensor to only be allowed to pull 2 degrees max under any circumstance.