Ls3 swap into 98-02 f-body w/ls1 currently

**leonardTA1999** · 01-10-2009, 11:15 AM

Good day to all who read this.. and thank you..

My question is what are the changes req for an ls3 crate motor from mast motor sports into an 1999 firebird trans am with an ls1 and t-56 in it now ?/

you can look at the motor and all that it comes w at paceperformance.com
under mast motor sports sub link at the bottom of there crate engines page..

MTM111-210 - Mast Motorsports Turn-Key LS3 427 Cubic Inch Crate Engine - 600 HP

everything i have now is bone stock as is from factory as far as the engine now. i just need input on the changes nesscary for this 427 ls3 to go in.
like will all of the factory sensors and acc`s still work with threre supplied computer and harness and will my gage cluster still work?? and is the factory t-56 trans bolt to the bell housing of the ls3 and can i use my ls1 flywheel on the ls3 and does the pan that comes w this crate work in an f-body and can i use my ls1 oil pan on the ls3 block.. see where im going with this ??

any help would be very much appreciated thank you..

Cpl Leonard J Ray usmc

**0verkill** · 01-10-2009, 12:01 PM

the ls3 will go in and blot to the trans fine. im not sure of the flywheel or the gages. the pc and harness will for sure need to be replaced to fit the new moter. and the pan need to be canged to fit the k-memer if i remember right. if you look online one of the mags did this swap and if i can find the mag i will post it for you.

**ls1camino** · 01-10-2009, 12:08 PM

Exactly what you're looking for:
http://www.ls1tech.com/forums/genera...02-f-body.html

Another bit of info:
http://www.ls1tech.com/forums/conver...onversion.html

**leonardTA1999** · 01-11-2009, 07:52 AM

Originally Posted by 01 t/a

the ls3 will go in and blot to the trans fine. Im not sure of the flywheel or the gages. The pc and harness will for sure need to be replaced to fit the new moter. And the pan need to be canged to fit the k-memer if i remember right. If you look online one of the mags did this swap and if i can find the mag i will post it for you.

thanks a mill ur info is priceless and much appreciated...

Cpl leonard ray

**shady milkman** · 01-11-2009, 08:33 AM

you need to make sure the reluctor wheel tooth count is the same. also the ls3 is a drive by wire...unlike our ls1's run by cable....also you will need a big time tune..