Alot of knock under boost? Also some tuning q's.

[Krisverde]

Ok car is a 1986 t type stock turbo with 3 in downpipe. Has the lt1 maf and maf translator with an extender chip. At wot and about 15 psi SM reads 820 mv and 14-15 retard knock. I know when he floors it you can hear a loud rattling and I believe it's the exhaust or the crosspipe or something that makes it. Actually sounds like loud ass ping...which I really hope it isn't ping if it's that loud. Any ways would the exhaust or crosspipe cause false knock?

Also here are some SM readings with the car at idle.
o2: 710, 714,726, 730 and 742 is what it read at idle, when the car first was started it was at 412 and went up.
af: 3
l8: 29
bat: 12.8
int:128
bl:119
clt:157
ats:140
r: 825-850
tps: .46
iac: 48
cc: 126

at wot the tps shows 4.46.

Thoughts on the readings here? I heard the af reading should be around 6?

 

[berserker6]

Absolutely exhaust can cause false knock. Not to say that yours is. Take a close look at the downpipe as it snakes its way down and make sure its not hitting anything. As for the ping if its from the motor you may already be in trouble. With the AF setting on your scanmaster watch it while you drive to see that it rises and falls progressively with throttle input. Around 6 at warm idle up to about 255 at wot. and make sure the settings in the translator are switched properly if insure ask. And do you have a way to verify fuel pressure while driving? if its a stock pump it will need to be replaced.

 

[Krisverde]

Ah ok sweet just wanted to be sure... Ill check all that stuff. Also I heard the translator was messed with to go through emissions? I am not sure how to adjust it either. No way to check fuel psi while driving either. Ill need to look around and see how some people run a gauge. Fuel pump was replaced but not sure what kind either I will talk to my buddy.

 

[87spools]

your tps is a little high. i would agree with about and start with fuel

 

[berserker6]

Krisverde its been a month. What did you find?

 

[TurboDave]

Absolutely exhaust can cause false knock. Not to say that yours is. Take a close look at the downpipe as it snakes its way down and make sure its not hitting anything. As for the ping if its from the motor you may already be in trouble. With the AF setting on your scanmaster watch it while you drive to see that it rises and falls progressively with throttle input. Around 6 at warm idle up to about 255 at wot. and make sure the settings in the translator are switched properly if insure ask. And do you have a way to verify fuel pressure while driving? if its a stock pump it will need to be replaced.

AF of 6 at idle is normal, EXCEPT in this case. He is running an Extender chip. 3 is perfect at idle and whatever you read at WOT you also have to double to get an actual flow number.

 

[berserker6]

Thanks Dave I missed that in his initial post. Would it be a hijack if I asked where could I go to see more about this extender chip?