need the big guns in here, knock problem on a super charged LT1

[Rhode Island Red]

Actually, I was directing my question to azkkn. Sorry for the confusion.

no problem ....

even when the mechanics are all working properly... it took a serious amout of custom PCM work along dyno tuning to get the setup stable... blower issues can be a major PITA

edit: you said it has 93k miles is on it .. what has been done to the optispark? you stated msd coil ... and others .. is it possible the opti is having issues?

[fastTa]

he has the 1ga011-sc kit, that is made to produce from 4.5-15 psi with the non intercooled psc-1. the 4~5 pounds he is running is exactly what the kit was designed to run.

By no means do I mean to sound like I am preaching, but with that kit and being non-intercooled, he will be lucky to see a 30 HP increase. I am dead serious. You have to remember that supercharged HP is NOT free horspower. With that kit pullied to make 4-5 lbs of boost it is almost taking as much HP to turn the head unit as the head unit is making additional power. In other words, if at 4.5 lbs of boost the p1-sc is going to give him a 25% increase over n/a, that would be approximately a 60 HP increase at the crank. It is taking roughly 30 HP just to turn the transmission and impeller of the head unit. So you are left with a grand total of about 30 HP if your lucky. Trust me, I've talked to ProCharger about this kit for an LT1.

I'm sure you already know this, but whenever you don't use an intercooler you are just asking for a tuning nightmare due to the very hot intake temps. Pre-ignition or detonation is just for a chance. He would really benefit from the use of a intercooler and then he would also be able to at minimum double the boost. You should never have to run race gas on just 4-5 lbs. With the proper intercooler, he will be able to easily run 9-10 lbs on pump gas.

[thomas]

Man, you guys sure know your stuff! I can only hope to one day have your guy's brain power. Well actually I really dont see that happening so I hope this board stays up along time!

[azkkn]

By no means do I mean to sound like I am preaching, but with that kit and being non-intercooled, he will be lucky to see a 30 HP increase. I am dead serious. You have to remember that supercharged HP is NOT free horspower. With that kit pullied to make 4-5 lbs of boost it is almost taking as much HP to turn the head unit as the head unit is making additional power. In other words, if at 4.5 lbs of boost the p1-sc is going to give him a 25% increase over n/a, that would be approximately a 60 HP increase at the crank. It is taking roughly 30 HP just to turn the transmission and impeller of the head unit. So you are left with a grand total of about 30 HP if your lucky. Trust me, I've talked to ProCharger about this kit for an LT1.

I'm sure you already know this, but whenever you don't use an intercooler you are just asking for a tuning nightmare due to the very hot intake temps. Pre-ignition or detonation is just for a chance. He would really benefit from the use of a intercooler and then he would also be able to at minimum double the boost. You should never have to run race gas on just 4-5 lbs. With the proper intercooler, he will be able to easily run 9-10 lbs on pump gas.

i went for a ride in this car, and it really didnt feel like it had a super charger on it. to tell you the truth, neither did the corvette that i am building when i first put the vortech on it. and with the boost levels he is running he should have no problems what so ever. i also learned yesterday that when the car was dynoed before the s/c was put on, the car was very low on power. My completely stock 94 Z made 238hp and i was told that he was way under me for power. he has a set of edelbrock headers (st) had a moroso cold air intake, and has a slp loud mouth exhaust. when he installer the s/c they had it perfect on the dyno, just a little rich, but good power all across the board, no sputtering, no knock. then he messed with the FMU and MAF and started having issues. he then installed a MAF translator and has beed messing with that. while the problem hasnt gotten worse, it hasnt been fixxed. i have set him up with some dyno time and when we can get it in there were going to run it with every sensor we can, including a wideband o2. we will see whats going on, personally i think the car is fuel starved at top end, and its either from the FMU being messed with (what ever he did to it) or a nasty fuel filter. my second guess is that the plugs are the wrong heat range. thanks for all the help, and keep the ideas comming. i want this car fixxed so i can blow him away when i put the dual intercooled (will be converted to one large intercooler) D-1 on my car, with my new motor, and afr heads.