I want to build a strong LT1. But I won't be assembling a shortblock. I'm looking at buying a complete shortblock. However, LT1 shortblocks with low mileage are few and far between. So I got to thinking about using an L31 Vortec 350 motor. They were in production until 2001 I believe, so low mileage motors should be easier to find, I would think.

But the real question is, can it work with LT1 heads, intake, opti and so on. I understand the compression is a full point lower than the Lt1, but with some nice heads and a cam, it shouldn't matter to much. Can the L31 take the rpms of LT1 H&C? I know the L31 has 4-bolt main and spins up to 5500 stock. It's not to far off from the LT1s 6000 rev limit.

Anyway, just a thought. Give me your thoughts, concerns, and ideas.

 

AFAIK, the Vortec is the same configuration as a regular SBC, so it has the same major differences to the LT1 in the cooling system category. Heads cold be modified, but the LT1 water pump would not even come close to fitting.

 

and you have to do other things...like drilling a hole for the dizzy,and making some room for it on the Lt1 intake.

 

I forgot to put that I would still be using everything from an LT1. aftermarket heads, LT1 intake, opti....but the waterpump still wouldn't work?

Or is an LT1 block my only option. Which is fine, I was just curious if a late Gen1 SBC would do the job.

 

There is no way an LT1 water pump would work or could be made to work. The water passages and mounting are totally different.

 

Like everyone has said if it could be done, we all would be doing it or have it already. Yes, it's a bummer.

 

The Vortec block is no better than a 4 bolt Vette LT1 block, so where's the beef?

Just build an LT1, Better than a standard small block anyway IMO.

David

 

Opti will not fit, there's no place to mount it. You might be able to cobble up some sort of external mount and drive, or mount the optical sensor in a conventional distributor, but most people would choose not to reuse the Opti if they didn't have to.

 

No problem thanks guys.

 

Just curious. You've all answered my questions. Thanks guys.

 

Not to bring up an old topic or steal the thread, am just curious as well... If you were to use a Vortec block to build an LT1, had the intake drilled for the distributor, had the heads worked over and all that, could you get away with an electric water pump for the Vortec or would there be clearence issues with the belt/accessories?

 

You either need to build a basic SBC (Vortec) engine or build an LT engine. They're like oranges and apples, completely different and too much trouble to try and mix and match the two of them.

If you've ever had an SBC engine and LT engine apart, the differences are "very apparent" (block water-pump inlet/outlet, timing chain cover w/ Opti mount, Etc.).

WD

 

I really really really really really wish some vendor would sell a LT block that could be bored/stroked safely over 400cid...

 

Me to! An LTx tall-block that would handle a 4"+ stroke and possibly 4.1" bore would be great! They make every combination of BBC block you can think of. All we need is one simple LT tall-block available and us LT guys would be in hog-heaven. Then we would have several options to work-with on our engine builds.

Cubic inches is always easy HP and torque!

WD

 

Don't hold your breath! As far as engines go, this is really a fairly small run, and the numbers are gettting smaller every day.
This is like asking for an aftermarket version of the old 348/409 block.