I'm now planning a bit deeper into my TT383 build. Looks like I may go for a World Motown Race block. My question is...Has anyone ever heard of problems with these smallblocks in the 800+ HP range?

http://store.summitracing.com/partde...5&autoview=sku

This is to be a 98%/2% street/strip 383 engine run on 93 octane and a full atmosphere of turbo; spun up to ~6200RPM. All forged internals, of course. I'm also open to Dart blocks or others, if you guys have any suggestions. As far as I can tell, this block seems to be already clearanced for a stroker application, but does anyone know if it's ready to go or will it need any special machining? Discounting unforseen circumstances which may present themselves (such as decking it and the like), does it look like I could just grab it and build?

 

I'm a fan of Dart blocks. Just personal preference. Done more work with them and I find that in general, they're cast better than the World stuff. Less core shift etc.

 

Not sure on the SBC castings but when I built my 540, I prefered the Dart Big M casting over World's Merlin 3 casting. Don't buy an aftermarket block strictly on price. Sometimes paying more gets a better product.

Very few aftermarket blocks are finished to the point of just assembling your parts. About the only ones like this would be a package deal that includes all the parts to assemble.

My block was just a bare block. No cam bearings, cylinders needed to be honed out, no gallery plugs, no frost plugs, no head dowls, no bellhousing dowls. All aftermarket blocks will have a factory deck height. To zero deck the block, you'll need to do an assembly to find out how much to machine off.

Unless you have access to a machine shop, expect to pay $500-$1000 more to get the block finished for final assembly depending on how much work you want done to the block.

 

The deck heights are usually off too. You can almost count on needing to deck the thing. You'll want it zero decked anyway. A BigM we're working on now was off .0011" side to side. Not to mention the deck surfaces aren't smooth enough for a steel shim gasket like a Cometic.

 

If your going with dart or world block go 400+ CI SBC forget about 383.

 

Ahh...very good stuff to know. I've never had to work with a new aftermarket block before. The World block I linked to was one I saw in a Summit catalog and it stated that it already had plugs & cam bearings installed. On the whole, I didn't expect that new blocks would be ready to go, but this "plugs/bearings" blurb was confusing the matter for me. They're making it look ready to go...but I guess that's good marketing. The Dart blocks on Summit vary all over the place in price and some of that has to do with preinstalled components, but if I'm going to have to have machine work done anyway, should I just order the bare block without cam bearings and have the shop install those?

For instance, this block has steel billet main caps and plugs & cam bearings installed for $2400:
http://store.summitracing.com/partde...5&autoview=sku

Whereas this one has ductile iron caps and no bearings or plugs for $2000:
http://store.summitracing.com/partde...5&autoview=sku

Immediately, it seems like a good idea to go with the more expensive block, but I'm tired so I'll do a bit more reading tomorrow. Also, I know these aftermarket blocks are stronger (the main reason I'm going for new aftermarket as opposed to a seasoned stock block), but at the power levels I'm going for, I don't anticipate needing a partial jacket filler with this block. Do you guys agree with that assessment?