knock

[dgreen]

Took my 87 GN out today, good fuel (93 sunoco), about 88 degrees outside , i got into it and looked down at scan master and saw 10.3 on knock! Backed out of it and it has not done it again. Should i be worried? or was it just a fluke? I try to mix 100 octane and 93 as much as possible. (Boost is set to 17 lbs. 42lb injectors and tt chip.) Any thoughts? Thanks

 

[HouTX87]

Something caused it. I'd keep an eye on it. Did you have 100 octane mixed when it happened?

 

[Ttype6]

Took my 87 GN out today, good fuel (93 sunoco), about 88 degrees outside , i got into it and looked down at scan master and saw 10.3 on knock! Backed out of it and it has not done it again. Should i be worried? or was it just a fluke? I try to mix 100 octane and 93 as much as possible. (Boost is set to 17 lbs. 42lb injectors and tt chip.) Any thoughts? Thanks

When you see spark retard,you should first suspect fuel pressure. You should be able to run 17 lbs of boost with just 93 octane.

 

[haywire4130]

When you see spark retard,you should first suspect fuel pressure. You should be able to run 17 lbs of boost with just 93 octane.

I'm having a similar problem, i get 3-5 degrees of kr during spoolup, i suspect a small change in fuel pressure will make it go away. I just installed my wideband yesterday and was very suprised how much the numbers differed from what the oe narrowband was showing. Could you make a suggestion if I posted a log file? I finally have my car to the point where I can start tuning but I dont really know what to change other than experimenting

 

[Ttype6]

I'm having a similar problem, i get 3-5 degrees of kr during spoolup, i suspect a small change in fuel pressure will make it go away. I just installed my wideband yesterday and was very suprised how much the numbers differed from what the oe narrowband was showing. Could you make a suggestion if I posted a log file? I finally have my car to the point where I can start tuning but I dont really know what to change other than experimenting

I'll take a look and so will others.

 

[dgreen]

didnt have 100 octane when it happened i did look at fuel pressure and i'm at 43 lbs at idle. (vac. hose undone)

 

[Ttype6]

didnt have 100 octane when it happened i did look at fuel pressure and i'm at 43 lbs at idle. (vac. hose undone)

You shouldn't need 100 to run 17. You need to know what the fuel pressure is at 17 lbs of boost. It should be 60 psi. It's also important to know what your O2 number is at full song.

 

[Pronto]

I'm having a similar problem, i get 3-5 degrees of kr during spoolup, i suspect a small change in fuel pressure will make it go away. I just installed my wideband yesterday and was very suprised how much the numbers differed from what the oe narrowband was showing. Could you make a suggestion if I posted a log file? I finally have my car to the point where I can start tuning but I dont really know what to change other than experimenting

The wide band and narrow band are hardly ever in sync. Narrow band reads a very small portion of the O2 range.