383 tuning question

[ShadowC4]

Hey everyone, I just finished building up a 383 for my 88 corvette. i tried using a TPIS tune, but it is running really rich to the point where it stumbles when shifting gears or holding a constant RPM. Can anyone tell me where i can find a new ECU or piggy back system to tune the air to fuel ratio. or any other ideas to lean it out Here are the specs: 383 ci 4 bolt 10 to 1 compression ratio comp cam 288 int./294 exh., 0.520 int./0.540 exh. lift Edelbrock performer heads. TPIS miniram 42 pound injectors headmen elite longtube headers. auto transmission 2500 stall

[bjankuski]

Originally Posted by ShadowC4

Hey everyone, I just finished building up a 383 for my 88 corvette. i tried using a TPIS tune, but it is running really rich to the point where it stumbles when shifting gears or holding a constant RPM.

Can anyone tell me where i can find a new ECU or piggy back system to tune the air to fuel ratio. or any other ideas to lean it out

Here are the specs:

383 ci 4 bolt
10 to 1 compression ratio
comp cam 288 int./294 exh., 0.520 int./0.540 exh. lift
Edelbrock performer heads.
TPIS miniram
42 pound injectors
headmen elite longtube headers.
auto transmission 2500 stall

Have TPIS redo the chip, I believe they will modify it for free until they get it correct.

Otherwise buy the programming equipment and do it yourself.

[Rohn]

Help them out and send some datalogs. you will need to but or make a ALDL cable. Otherwise they will be doing some guessing.

[Paul Ruggeri]

Moates.net has what you need if you want to tune it yourself. 42 lb injectors? Are you planning NOx or a supercharger?

[ShadowC4]

nope i am just planning to run it natural. shooting for 500 + horsepower.

[getnakd]

drop injector size, and look at alpha and o2 at full throttle under load. check fuel pressure if adjustable lower until you reach you desired alpha then lower it 2more psi for driveability if pings add more pressure