Hey Folks
Anyone noticed that no one has stock on the L31 engine
I am in Canada ,but checked Jegs,Summit etc.
Just curious,as I am interested in one of these.
Thanks
Shawn

 

Bad timing. There were current events causing manufacturing delays before the WWFFO (World Wide Flu Freak Out) so it might be awhile before things go back to normal.

 

Thanks Drew,
I thought as much,
I gotta get that 305 out of there! Lol

 

If you opt to get something used and already pulled in Ontario or Michigan, check out www.car-part.com

For me the thing about getting a new GM engine is that it is still a stock engine. Canadian dollar is bad right now and this engine will likely cost around $3100 CAD, then you spend a day driving to Michigan and back in a truck to pick it up somewhere you paid to ship it to, then customs punishes you on the way home for an additional 13% on $2200. You're in it for $3500-4k cad just getting it home. Then you have to drill the fuel pump hole out if you want to use a mechanical pump, buy a vortec specific intake manifold, camshaft because there is no fuel pump lobe, springs and retainers, timing cover... To me it's not worth it. Last I looked years ago GM really didn't offer a warranty either on engines outside of the USA.

There are plenty of L31 trucks in the u pull boneyards around Detroit area for even less money if you're willing to get a little dirty. You can tear into them a little that way to and make sure there's nothing catastrophic You'll want to toss the stock intake anyways, so you'll be able to see in the lifter valley if it had regular oil changes or not. I pulled my 4 bolt main vortec out of a k2500 for under $200 usd w/core.

 

Good info,never considered doing it that way.
Thanks

 

Most recommend a vortec from a 1996 to 2000 3/4 ton and 1 ton gm truck,is this to obtain the 4 bolt main?
This opposed to a 1/2 ton which would be 2 bolt main?
Thanks

 

unless you're building a motor that you're boosting or spraying with a 400 shot, you don't need 4 bolt mains..

 

The 96 - 2k motor has the good Vortec heads. Before that, up to 95, they were TBI swirlies, which you DO NOT want. 2000 was the last year, for the most part. There are oddballs here and there; maybe marine and/or applications; but as far as just what you'll generally find in a typical junkyard, 96-2k.

 

So my daily is a '03 Chevy PU, with 5.3, I thought it was an L31?

I also have a '01 Yukon out back with some real bad electrical gremlins with a 5.3 as well.

Are these not the L31's? Both say Vortec on the plenum covers.

 

Vortec 5300. LS based AFAIK.

 

Is that different than the L31?

 

The L31 is a Gen I type small block, not an LS based engine.

 

I gotcha

 

The L31 is a traditional small block Chevy; 55 - 2k.

Main thing about it is, it has those good heads. Other than that, with minor detail differences, it's the 65-yr-old SBC motor.

The 99 - present motor in trucks and cars - 4.8, 5.3, 5.7, 6.0, 6.2, - is what we call the "LS" motor series. COMPLETELY different. I doubt ONE SINGLE PIECE interchanges; not even bolts or spark plugs.

96-2000 trucks. That's what you need to be looking for. The L31 came in those.

 

The only thing the old engines have in common with the newer LS style engines, is bore spacing... Totally different engines

 

Actually, I take that back... there are some things that can be swapped between the old SBC and the LS series sometimes… the lifters interchange (LS ones fit a SBC roller block); push rods, if you happen to need that length (retrofit roller setups in SBC sometimes can want push rods near the stock LS length of 7.400", and they're both 5/16" or 8mm); and valve springs, but only if you use special "swap" retainers (the valve dia is different).

 

Thanks Sofa,
So any difference for one from a 96-2000 1/2 ton ,as opposed to 3/4 and 1ton truck applications?
Shawn

 

I don't think so. AFAIK they're all pretty much the same.

 

Ok ,the reason I asked was,I noticed a lot of threads mention finding engines from 3/4,1 ton applications,just was curious why
Thanks again

 

Don't know; maybe it's just what they happened to come across.

 

Rod bearings interchange as well.

 

I think the 3/4 and 1 ton applications had a 4 bolt main and the 1/2 ton were 2 bolt. Unless you plan on going crazy with power, a 2 bolt works fine.

 

I think folks just feel that a 3/4 or 1 ton engine would be tougher/able to take more power.

Placebo thing IMO.

 

FWIW my vortec is out of a 97 k2500 pickup. I had it bored and honed .030" over and made a 383 out of it. My machinist said it is one of the hardest blocks he has ever bored, he couldn't rough cut the bores anywhere near as aggressively as he normally does. He said it is harder than Dart blocks he has done. I guess I can believe it, it didn't need to be bored. So they may have done a different pour for the hd castings. If you can get a 4 bolt for the same money as a 2 bolt, why not? Also, hd trucks should have hardened seats in the heads, not the induction hardened treatment the light duty trucks got.

I have found what this guy says to be true:

 

Everyone knows about the heads, lack of lift attainable in factory form, and need for a Vortec specific intake manifold. But the block has a couple things going on that are not common in other years of sbc.

-Some of the Vortec 880 blocks don't have the water pump bypass hole in the block or the bypass passageway drilled from the passenger side of the block. Mine was all there though.

-Vortecs aren't drilled into the crankcase for mechanical fuel pumps, nor do they have cam lobes to drive that style of pump.

- Vortecs use a shorter snout on the harmonic dampers, because they have reluctor rings inside. I think the damper is also a larger diameter than what is on our fbodys.

-Vortecs use plastic timing covers. Some don't have all the holes for a steel cover. Mine had them all, just had to install a couple dowels and correct bolts for a stamped cover.

This probably goes for all roller sbc blocks, but to run a double roller chain, you have to grind clearance for the chain above the top galley plug. Also, there was a ball bearing instead of a plug in one of the main oil galleys into the block above the rear main.