PCM Question - 5.3 motor to LS1 - Problems?

[93blackbeast]

Hey guys,

I've already swapped out an 04' 5.3L in my 1993 OBS and the thing works like a champ. The plan originally was for this 5.3L to be an "in the mean time" thing and work until I could get my LS1 rebuilt from my Trans Am. Well, that time is here now and I'm ready to swap the LS1 in for the 5.3. This should be a lot easier swap than starting from the old 5.7 motor, but I have a question about the PCM.

Will I have any issues getting the LS1 to run with the PCM from the 5.3?

Thanks,

Cody B.

[George C]

you need to have the tune adjusted for motor

[carfreak07]

it will run fine as long as you are still using the same intake setup. If you were using a truck intake then stay with it, if you were using a car intake then stay with it. You can change but if so you need to adjust your Injector flow rate vs vaccum table to make it run. Hope ya get it figured out. Like the above said, you will need to tune it for maximum performance. There are a few parameter that can be changed but it will run ok the way it is.

[93blackbeast]

it will run fine as long as you are still using the same intake setup. If you were using a truck intake then stay with it, if you were using a car intake then stay with it. You can change but if so you need to adjust your Injector flow rate vs vaccum table to make it run. Hope ya get it figured out. Like the above said, you will need to tune it for maximum performance. There are a few parameter that can be changed but it will run ok the way it is.

I will be swapping the whole LS1 over, accessories and all, keeping the LS6 intake that's on it. The one main change I have to do to get the car to plug up to the new motor is to splice my harness for the car injectors and THEN I'll tune it to suit.

I already have the tune for this motor because it was in my Trans Am, so I just plan on duplicating all of my tables from the car for a start just to get close and then tweaking afterwards for my headers and exhaust, shift points, and so on.

Thanks for the input.

[George C]

Tune is the safest way possible and will get best results. thngs will run but doesnt mean it runs right.

[93blackbeast]

Thanks for the response guys.

And I'm fully aware that I'll have to tune it, I just wanted to make sure that it would be feasible to tune it (correctly) to run an LS1. I have tuned a couple of Gen III engines with HP tuners and don't have a problem at all, but someone once told me that i would need a PCM from an LS1 in order to get it tuned right...something about a displacement calculation in HP Tuners...

I've been through the software pretty in depth, but I don't recall coming across something where it actually mattered if the PCM knew the displacement. All I know that is critical is the VE, spark timing, etc. tables....if I get those in, I would think I'm good.

Does that sound right?

Thanks,

Cody B.

[George C]

the table your referring to is something 90% of ppl over look. its in the engine section on first pop up on the left of page

[93blackbeast]

I haven't got to look at the table that you're talking about Quik but can that table be edited?

[George C]

yes, it needs to be changed for any motor size you run

[chevyz7120]

guna be selling that 5.3?