I believe both of you have expressed the opinion that all LT1 replacement blocks have 4 bolt mains.
Have you or anyone else been able to establish this as fact or are we still in the belief mode?
Thanks.

 

Who's under the impression that LT1 blocks are stlil made??!... As for the ones they used to make, I thought that both the 2-bolt and the 4-bolt variety were available (different part numbers).

-Michael

 

I can't remember where I picked that up. So... no, I cant prove it.

Not sure why you feel you have to call us out on something like this

 

To begin with: I'm pretty sure that GM ceased to produce Lt1s (2-bolt/4-bolt) a long, long time ago. And when they cease production, the inventories are probably sent to dealerships where the engines are still under warranty periods and after that to anyone who will take them.

As far a 4-bolt as replacements, my guess is that if they had lots of 4-bolts left over, that your chances of getting one as a replacement might be good. I doubt that it was a policy per se.

And as far as getting even a new 2-bolt shortblock, they might be getting a bit short in supply.

When I looked for a shortblock a few months back, I happened to find an ad at Sallee Chev. here in Oregon. It said they had 9 4-bolt engines for sale. I immediatelly called and ordered one. They had to check their warehouse to see if they still had any. Their ad still says they have 9, but I doubt that they have any now.

 

No one. Were talking about engines that were replaced under warranty.

Not at all! Just trying to keep the post short, sorry.

I often "know" the answer to a question but can't remember from where. Just attempting to ask you if you might have gone back and check or now remember.

Again, absolutely no desire to: denigrate, malign, asperse, bespatter, blacken, calumniate, defame, libel, scandalize, slur, smear, spatter, tear down, traduce, or vilify.

 

Sleeping with the thesaurus under your pillow again, eh?

I don't have any official source, but everything I have read leads me to believe that warranty blocks had 4 bolt mains. I do know that numerous people that had gotten replacement engines under warranty, indeed got 4 bolt main blocks.

 

Thanks,
Sure would have liked to nail this down without pulling the oil pan.
Seem my 97 had the engine replace around 37,000.

 

Hey Shoe: What's intriguing about that assumption is perhaps an underlying assumption by the manufacturers/engineers that the 4-bolt would probably fair better against the tolerances of the assembly line engine.

The 2-bolts were probably cheaper to produce, but occasionally replacing one with the stronger assembly would placate those consumers who were unhappy that their new engine bit the dust early on.

Could happen.

 

Another guess would be for money reasons they elected to only keep one block in stock, rather than two. The 4 bolt one could be used to replace Corvette or F-body (or even B-body, I suppose). You can bet it had something to do with $$, one way or another.

 

So if you got a replacement 4-bolt block from the dealer, and put LT4 heads/cam/intake and injectors, ect. would it be fair to say you had a "real" LT4 engine?

Brad

 

No, because it wouldn't have the LT4 crank, LT4 pistons, and the LT4 "cambered" piston rings.

 

That sounds right to me. And yes indeed, its all about costs per unit and profit.

Obviously the LS1 has been planned for many years. Most know that better flowing heads produce more power.

Hell, even cleaning up stock heads, providing extruded manifolds and as hair bigger cam could have equaled the performance of the Lt1 vis a vis the Ls1.

It's all designed. And always will be.