Hey guy's! I have been haveing an issue with knock retard ever since my supercharger install. When I first stomp on it I get knock retard and then it goes away. Anyway I am trying to tune it out but I still want it to pick up knock other than when I stomp it.
What I have done after several attemps is lowered my knock fast attack rate to 0. This has goten rid of knock retard when I stomp it but I don't know if it will allow knock retard in other area's.
Does anyone know if I just got rid of the knock fast attack retard or did I get rid of knock retard altogether?
I am working on a 95 LT1, OBD1. Thanks

 

Are you sure that you aren't actually getting true knock when you "stomp on it"? If not, eliminating the knock retard may not be the best idea. It would seem like you might want to "tune it out" by pulling some timing or richening up the mixture, unless you are absolutley certain it is "false" knock.

 

Thanks for the reply Injuneer. I have tried to tune it out by richening it up, pulled timing down to 18 degrees, and also tried 100 octane race fuel and it didn't help.
Do you know if what I did will just eliminate burst knock or will it eliminate knock retard altogether?
I am thinking it might just be a noisy supercharger.

 

I don't know much about tuning the stock LT1 PCM.... I got rid of mine more than 8 years ago. There are a lot of others here who have that kind of knowledge. You just have to keep pushing the post back up to the top with a "TTT" every few days, and hope one of them reads it.

 

Did you shut off burst knock, zero out 'Burst Knock Retard Vs Coolant Temp' to eliminate it from the equation ? -Or- do you have burst knock and your concern is killing the KR attack rate will also prevent burst knock retard. Sorry I can't answer your OP, I don't know if killing attack rate will kill burst and/or KM detected (real or false) or separates them. Maybe an e-mail to TunerCat asking the question, not a lot of free ODB1 design stuff around to research.

 

I have zeroed out knock fast attack rate and cocerned that it might eliminated knock retard altogether. It isn't reading any knock now.

 

I use LT1_edit version 2,2. OBD2 PCM. I had alot of roll back on the timing with the knock sensor. My app is a 97ss 383 with a D1 Procharger running a large Spearco and also Meth/ H20. Still had the knock retard and very poor performance with the timing roll back. Headers and roller rockers tend to trigger the knock sensor. I eliminated all the knock timing retard in the flash program. Runs great now.

From my experimentation, these LT1 engines really like alot of advance timing. I have experimented with running 20/24 degrees @ 100 kpa, but the motor really responds well to 32 to 34 degrees advance. I run 34* with 15# boost now. I also run a large intercooler and meth/ h20 injection. My afr is approx 12.8:1 @ full WOT.

 

Thanks for the reply mzgp5x! Good information. I would like to run a big intercooler but there isn't much space under the hood of a 95 vette. I have also been thinking of a water injection system. Could you tell me what your running for a water injection? Who makes it, where did you get it and are you running a MAF kit or does it inject of from boost?