Detonation Problem Solved

[scott_s]

Ever since I picked up my OTC scanner in Feb I have been recording knock. I backed the timing down to 10^ and was running 8psi for boost. I recently found my misplaced AFPR. After a little polish I put it on. No more detonation. Upped the boost to 12psi and no problems. Tomorrow I will up the timing and the boost a bit more and see how the knock goes. Things are looking good with the car.

Scott
88 Daytona Shelby Z
www.sheenconsulting.com/car

[oldgregg]

So what your telling us is you didn't have enough fuel.

Did you: check FP with the old reg & then the new reg?
Do you have an A/F gauge & if so, what was it reading before & after the swap?

[glhsken]

Scott.. More info. I remember well that knock made no sense at all. Was the old reg bad?? That would explain not enough fuel.

[scott_s]

It does look like not enough fuel. It does appear that the old FPR was not working well. With the old one I could get lots of knock (was not all the time). With this new one (set @55psi at idle), so far, I have recorded no knock. That is with increased boost levels. Today I will try to put the timing back to 12, maybe even 14 if all goes well.

The old one I had tested before. I put a fuel gauge on and at idle it was 58psi. I even had a garage double check it with theirs when the car was boosting and the pressure was going up accordingly. Of course when they tested it, no knock was recorded. With that info, I did not think it was bad. Recently, I thought I smelled gas in the FPR vacuum line, but it was very faint.

I had been getting the odd code 13 (fuel in the vacuum lines??), and that is with new baro/map, and vacuum lines. Other driveablity issues such as hard starts sometimes, bad baro like behaviour, and acceleration issues. Since the new AFPR none of these have reappeared.

Yes, I have an A/F. It does seem to read richer than before. The data logs diffinetly read better. The O2 readings are much higher than before. I had .92- .96 before and still showed knock. I see 1.02 .98 now. The O2 pattern appears different now.

It is only the second day, so I may be jumping the gun, but I hope not!

Scott
88 Daytona Shelby Z
www.sheenconsulting.com/car

[glhsken]

Quote:

I had been getting the odd code 13 (fuel in the vacuum lines??), and that is with new baro/map, and vacuum lines. Other driveablity issues such as hard starts sometimes, bad baro like behaviour, and acceleration issues. Since the new AFPR none of these have reappeared.

thanks, You might have just helped me out...

[amoparacer]

I just installed the Forward Motion regulator on mine set static to 56 psi made a big diffrence in power blow all the controler lines off under full boost 14 psi and a little surge Im using the MP 2 computor on my GLHS with no bleed off ie grangers. Car now has zip ties on all port. Wish someone would do a first 5 modes tech post for the new kids on the block. PS do not buy fabtec AFPR they have non correct inlet to fuel rail nipple leaks like a sive yes Ken I tryed the washer trick still leaked.

AMOPARACER LYnnPeterson

[glhsken]

The reg is awesome. Yours will still leak if the inlet was scored. It will slit the new O-ring as it goes in. You will need to polish it out.

1st 5 mods
exhaust
stage II GLHS LM
+20 inj
Adj reg
Grainger and overboost prevention.

Just that and a GLHS can get you a 12 second car.

[scott_s]

I was a little over zealous I guess...

At the 8psi I was running no knock what so ever. Increased to 10psi still no knock. Had some knock at 13-14.

I put in my 40+ injectors, I have adjusted the fuel pressure so that at 12 psi of boost the O2 is .96v. I still get the odd time, 1-2 degrees retard in cyl1 and sometimes cyl4. Still running 10^ for timing, although I do want to change that soon as I can borrow a friend timing light.

[csxt#10]

Quote:

Originally Posted by glhsken thanks, You might have just helped me out...

had that problem a ruptued feul pressure regualtor caused the hard starts and all had alot of fule in the vac lines