Jan 22, 2013 · So I've done a bunch of research on throwing an L31 Vortec motor (96+) into a 95 OBS and bolting up the GM Performance manifold that converts the standard TBI to the Vortec heads.

Feb 10, 2016 · I have a new crate L31 engine, Muncie 4-speed, and plan on upgrading the valve springs, spring seats, guide bosses for a higher lift cam. Probably going to use a ZZ4 cam or something on that order and long tube headers.

Oct 17, 2022 · The 87 through 95 TBI cop cars got a roller cam with 180/194 .050 duration with .392/.401 inch of lift at the valve with a 109degree LSA. The L31 Vortec roller cam times 191/196 at .050 with a lift at the valve of .414/.428 using a 111 degree LSA

Aug 11, 2023 · L31 cam specs: .414/.428" lift, 191/196° duration at .050", 111° LSA. The stock TBI cam is laughably lame. If you're buying a junkyard motor, why not just aim for a Vortec from the start? You can run a Vortec longblock with a TBI adapter on a Vortec "carburetor" intake.

Jun 10, 2012 · For a budget performance engine, I think the L31 / TBI combination makes for a good dollars and cents build! The Hypertech .bin needed lots of help with the timing table:yikes: to work with the L31 Vortec roller camshaft.

Aug 5, 2017 · The only L31 to TBI intake that includes EGR is from GM at 460 dollars, the same thing from GM but to a carb is 350 dollars. The aftermarket does not provide either with EGR and the Vortec bolt pattern.

Nov 19, 2020 · The L31 roller cam is quite similar in timing to the old 300 horse cam used in the high compression 327 and the lower compression 350 both with 4bbl carb back in the late 60’s early 70’s. Going beyond that takes a custom chip in the TBI computer.

May 22, 2020 · The car is currently lowered and has been swapped to a 1998 Tahoe L31 engine hooked to a T5 5 speed manual. The engine is currently being fed by a dual plane intake manifold with an Edelbrock carb. I still have most of the original EFI gear from the Tahoe.

Jan 10, 2016 · I was looking at doing the same thing - the L31 crate is a great value (roller cam, vortec heads, 4 bolt mains block) for right around $2k. You'll need a TBI/Vortec Intake from GMPP which is pretty spendy to make it work.

Nov 5, 2016 · The L31-R will require a vortec style intake, or you will have to re use your TBI heads. Its pretty common to use a Vortec Carb style intake and use an adapter to mount your TBI. The L31 also is a roller cam block instead of the old style flat tappet.