I have a very simple, basic question to ask.

What is the difference between an engine block used on a corvette versus those used in a camaro or a truck?

I ask this because, at some point, I would like to rebuild an engine to put in my vette. I want a good block as a starting point for any rebuild. So which block is best for this purpose.

Did they do different casting numbers for accounting reasons? Is nickel content significantly different between blocks?

Thanks
Ryan

 

ZIP !

 

:yesnod: Oh yes there is a difference in blocks. Earlier blocks had much more metal around the bores – allowing some very large overbores. Some can be bored 1/8”.
And there are blocks with higher nickel contents. Under the timing cover a 10 or 20 number is cast into block indicating higher nickel alloy.
Too much to type about now but hereÂ’s two books that should help.
1 – How to Build Max Performance CHEVY SMALL BLOCKS on a Budget, by David Vizard
2 – Chevrolet Small Block Parts Interchange Manual, by Ed Staffel

I can’t remember if any small blocks have higher deck heights (like big blocks) on truck motors but this only a concern for large strokers (over 3.75”).
For a street motor I think price for a good low mileage rebuildable core is more important than nickel content or even large overbores.
I guess what IÂ’m trying to say is for a street motor your time and money is better spent on other parts as the difference in power you may hardly feel. :steering:
Now racers running over 600 hp small blocks need thicker stronger blocks to squeeze out higher power and stay together - with cams, induction, exhaust that you canÂ’t use on the street. :lol:
BTW that's a very nice corvette of yours Ryan. :cool:


[Modified by cardo0, 11:03 PM 10/30/2003]

 

There ARE differences in blocks. BUT none of them are exclusive to the Corvette. The most reliable source for 4 bolt main blocks, are trucks. Most, mid '70s to early 80's, Corvettes are 2 bolt blocks. There are no tall deck sbc's. Cylinder wall thickness is matter of production year. Later blocks are "thin wall" to save cost and weight. No 350 should be bored .060" or over without sonic testing the cylinder walls for thickness. This is due more to "core shift" (a production tolerance) than whether it is a "thick" or "thin" walled blick. The point is, among all the differences in small block blocks, none of them are because they came from a Corvette. Chevelles, Camaros, trucks, and others can be the donors of a great block.

Therefore, in responce to the question:
I answer: ZIP

RACE ON!!!


[Modified by CFI-EFI, 9:22 AM 10/31/2003]

 

:iagree:

 

:conehead Now the part numbers are fairly generic in that the same number is used for different bore sizes, stoke sizes, 2 or 4 bolt main, and vary generic for vehicle applications (car & truck). And the only way to identify a 1% tin block is with a 010 number cast under the timing cover. Or a 2% nickel block with a 020 in same location. But the casting numbers do identify which years of manufacture – which is important to some enthusiasts. Also the 400” blocks had number 3951509, 3951511 exclusive of smaller displacement blocks. So lets never say never here. :p:
Now if you really have the fever you can buy race prepped blocks from GM Performance Parts in tall deck for strokers at 9.150” (#24502525) or Rocket Block (#22551790) at 9.325” and even taller in aluminum – if you dare. :chevy

 

First! I never said that there weren't differences in blocks. I was responding to the author's question. Maybe you should reread it.
The correct answer to that question, is, NO DIFFERENCE.
The PART numbers are specific. A block of a given PART number will have a defined bore. It will have the mains called for by THAT part number. It will have the metalurgy called out for THAT part number. CASTING numbers are generic. Once the part is cast, it can be machined into multiple PART numbers. That is one reason you can't tell a 4 bolt main block by the cast number. Other than the main cast number, like you make reference to, there are date codes cast into the block. These are important to restorers.

The 400 blocks have unique casting numbers because they are unique castings. No other production SBC could ever accomodate a 4.125" bore. No other SBC had siamesed cylinder bores.
These are NOT production blocks. What can be obtained and the differences in Corvette and truck blocks, are two different things. I refer you back to the origional question.
The full, complete, answer to THAT question, is ZIP !

RACE ON!!!

 

:conehead Well I did re-read the question and he further explains he is looking for the best block to rebuild for his car. Also Ryan asks two more questions one of which address nickel content, which you did not address because you cannot identify it without removing the timing cover. Which blocks in which cars had the high nickel content? No, not ZIP. Now I think the choice of production block or other is his and asks “I want a good block as a starting point for any rebuild. So which block is best for this purpose.”? Now a 400” block is very popular retrofit now in C3 corvettes (and C2s) but you couldn’t say it was the same as any corvette block.
Yes I did say part numbers are generic when I should have said casting numbers. Big deal. So call a cop. See if he cares. :p: :p: :p:


[Modified by cardo0, 9:57 PM 11/1/2003]