64 289

[Rick Parker]

There have been from time to time on Ebay (and other place) advertised 4 bolt caps to the used as a replacement on "Stock" 2 bolt blocks. HOWEVER, from what I recall there isn't a lot of material (thick webs?) for the outer bolt holes to be machined into, otherwise I think it would be a more popular conversion. Anyone else have any coments on this ????? I also would have liked to see a forged steel crank available for 289's. This is one area it seems like Chevrolet always had a leg up on Ford, their cranks for the most part were forged. Although the cast cranks did OK, the "Little Bird" is always sitting on your shoulder, whispering in your ear as the tach goes past 7000 rpm??

[olddog]

Originally Posted by Rick Parker

There have been from time to time on Ebay (and other place) advertised 4 bolt caps to the used as a replacement on "Stock" 2 bolt blocks. HOWEVER, from what I recall there isn't a lot of material (thick webs?) for the outer bolt holes to be machined into, otherwise I think it would be a more popular conversion. Anyone else have any coments on this ????? I also would have liked to see a forged steel crank available for 289's. This is one area it seems like Chevrolet always had a leg up on Ford, their cranks for the most part were forged. Although the cast cranks did OK, the "Little Bird" is always sitting on your shoulder, whispering in your ear as the tach goes past 7000 rpm??

I have heard some builders say not to put 4 bolt caps on 2 bolt blocks for that very reason.

Chevy only put the steel cranks in their high performance engines. The rest got cast iron. The Chevy small journal engines did break quite a few cast iron cranks, which is why they stepped up to the large journal. I never heard of a small journal steel crank breaking, but I'm also not in a position to know all things.

[YerDugliness]

Originally Posted by Rick Parker

There have been from time to time on Ebay (and other place) advertised 4 bolt caps to the used as a replacement on "Stock" 2 bolt blocks. HOWEVER, from what I recall there isn't a lot of material (thick webs?) for the outer bolt holes to be machined into, otherwise I think it would be a more popular conversion.

I think a set of cross-bolted mains would be great.....not sure if there is enough skirt to bolt to, though. The mains would be quite "wide", that's for sure!! I could see an extra pair of small diameter main bolts in the webs and two more cross-bolted in. Sounds like it would be a great setup and not require a main-girdle.

Cheers from Doug

[blykins]

For 302 based engines engines between 400-450hp, I don't use main girdles. A good set of ARP main studs seems to do just fine. When the engine comes close to pushing 500hp and/or turning some high revs, then I do what I can to stabilize the bottom end.

Four bolt caps in a small block really isn't accomplishing much. As some of you have pointed out, there's really not that much material there and you take a chance of just making things weaker. As a matter of fact, 2 bolt Cleveland blocks are preferred over 4 bolt Cleveland blocks. This goes the same with 2 and 4 bolt Chevy 400 SBC blocks (unless they're aftermarket).

On a skirted block (like an FE, LS, modular Ford, etc), crossbolted main caps will significantly add strength and are a good idea.