New 383 with stock LT1 program, will it run?
Thread Starter
Burning Brakes
Joined: Dec 2001
Posts: 901
Likes: 15
From: Punta Gorda, FL
New 383 with stock LT1 program, will it run?
First post in this section, a new challenge for me.
Have a new 383 going in my '95, will be done by Tues. Have purchased a pcms for less program to get the engine broken in, and then will decide on further mods and/or dyno tuning. Have not changed the program yet since the PCM was out of the car. Mechanic is paranoid to have me change anything before he gets the engine in and started. He says it 'should' run on the stock program. A local tuner also said it should run on the stock program just to get the first 20 minutes done and the car driven home. Looking for info from you all. What will be 'off' on the tuning with the stock program? Will I risk any damage due to rich or lean conditions? Your opinions please.
383 LT1 4.03 bore/3.75 stroke
5.7 rods, 48 cc chambers, 23cc dish pistons, .042 quench, 10.75 compression
Ported heads with bigger valves
LT4 Hot Cam, 52mm TB, 30lb FMS/Bosch injectors
stock MAF, FPR, fuel pump
Thanks for the help.
Have a new 383 going in my '95, will be done by Tues. Have purchased a pcms for less program to get the engine broken in, and then will decide on further mods and/or dyno tuning. Have not changed the program yet since the PCM was out of the car. Mechanic is paranoid to have me change anything before he gets the engine in and started. He says it 'should' run on the stock program. A local tuner also said it should run on the stock program just to get the first 20 minutes done and the car driven home. Looking for info from you all. What will be 'off' on the tuning with the stock program? Will I risk any damage due to rich or lean conditions? Your opinions please.
383 LT1 4.03 bore/3.75 stroke
5.7 rods, 48 cc chambers, 23cc dish pistons, .042 quench, 10.75 compression
Ported heads with bigger valves
LT4 Hot Cam, 52mm TB, 30lb FMS/Bosch injectors
stock MAF, FPR, fuel pump
Thanks for the help.
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Re: New 383 with stock LT1 program, will it run? (lspalding)
It will probably tolerate the Hot cam but it won't like the larger injectors. Your stock injectors were 24lb/hr units and having 30lb injectors will cause it to run very rich. If you want to stay with a stock program then just install the stock injectors, it will run fairly well with them.
If you can reprogram your PCM, then I would change the injector constant to 30lb to relflect the injectors you have and also bump the idle speed up to 800 RPM. It will then run fine with the hotcam. Or use the PCMs for less calibration that you purchased.
If you leave the 30lb injectors in the engine and try to run the stock calibration you will be asking for problems. Its going to be a bit rich from the cam anyway and the added fuel that the PCM don't know about is going to compound the problem.
If you can reprogram your PCM, then I would change the injector constant to 30lb to relflect the injectors you have and also bump the idle speed up to 800 RPM. It will then run fine with the hotcam. Or use the PCMs for less calibration that you purchased.
If you leave the 30lb injectors in the engine and try to run the stock calibration you will be asking for problems. Its going to be a bit rich from the cam anyway and the added fuel that the PCM don't know about is going to compound the problem.
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: New 383 with stock LT1 program, will it run? (tjwong)
That's almost the exact same setup i had with my '94 :cool: :cool: . I had higher compression though (11.55:1). It will "run" to get it back to your house.
I didn't look to see if you have an auto, but if you do, it might kill it at the lights on the way home (oh well). When you get it home, definitely have to raise the idle and change the injector constant. Need to get some logs done with Datamaster to see how your fuel is - it will probably be off. Also need to pull some timing with the 383.
Congrats on the new engine! :cheers: Be CAREFUL with it!! :rolleyes:
I didn't look to see if you have an auto, but if you do, it might kill it at the lights on the way home (oh well). When you get it home, definitely have to raise the idle and change the injector constant. Need to get some logs done with Datamaster to see how your fuel is - it will probably be off. Also need to pull some timing with the 383.
Congrats on the new engine! :cheers: Be CAREFUL with it!! :rolleyes:
