I need some opinions on which block is better overall. It is between a 351 block, siamese bore or non-siamese bore? Also, which deck height is better, 9.200" or 9.500" and why? I want to possibly build my own engine from one of these new blocks, stoke it to a 408, but I am not sure what the advantages are. I know the siamese bore doesn't allow coolant to flow between the cylinders. Thanks.
The siamese bore is more stable at high rpm's and heavy loads. But it doesn't cool as well. If you're going to use a mechanical cam and run the rpm's to 8K, get the siamese block.
Deck height doesn't really matter that much. But you have to get the right parts to fit the block. That means pistons and intake manifold.
Siamese bores are stronger blocks. It depends on how much power you plan to build. And 9.2 is Cleveland deck height and 9.5 is Windsor deck height, it's easier to get stuff for a 9.5 DH block, since 9.2 limits you to fewer intake manifolds.
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Who cares how much horsepower it has, all that matters is how fast it goes!
Best run 13.23 at 106.97mph with a 2.183 60' Times from before tune and driver mod.
Yeah I was looking at those dart blocks too. I 've heard good things about those, heavy duty blocks. How is the cleveland crank different? I will definately go with the siamese block though, it looks like that is the bore to go with for my application. I want to push about 450hp and the same for torque, if not alittle more.
Cleveland journals are smaller so there's less drag. And for 450hp there's no need to waste money on an aftermarket block. A stock 302 block is good to 500-550hp if tuned well, and a 351W or C stock block will take 600-650 safely. A basic 351W build with good heads and induction will make 450hp easily at around 6,000rpm.
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Who cares how much horsepower it has, all that matters is how fast it goes!
Best run 13.23 at 106.97mph with a 2.183 60' Times from before tune and driver mod.
Canfields aren't basic. But yeah, a set of Canfield heads, a custom solid roller, Air Gap intake and some lightweight internals with a good carb, that'll definately get into the 450hp range, prolly closer to 500.
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Who cares how much horsepower it has, all that matters is how fast it goes!
Best run 13.23 at 106.97mph with a 2.183 60' Times from before tune and driver mod.
Pushing 500 would be great. Are there blocks available that can be bought that are already machined and ready to begin a stroker build? Most of the blocks I've looked at need machined to take it from the base 351 to the 408 stroker. What sort of block would be good for the 500hp range? I want the hydraulic rollers, al heads, etc. I just don't want to get a block and realize later there was a better block I should have used instead. I'm not going to be racing but I want to be able to get on it if I want to.
Deck heights make a big difference. 9.2 is a Cleveland. 9.5 is a Windsor. Which you go with is going to depend on what heads, intake, etc you want. If you get a Dart Sportsman, which is what I did, you can get it in both varieties. In fact, you can also get it in a 302 version. Both 351 Dart blocks use Cleveland size main journals and require a Cleveland crank, so you will need to get a custom rotating assembly if you get 9.5 version. It is not that big a deal because you will probably want custom pistons and rods to get you compression height and compression ratio where you want it.
As for horsepower, I belive the Dart Sportsman is good upto 1200hp and 460cid. I personally thing that is awesome for the money. The Iron Eagle is basically an all out race motor and is way over kill for most of us. When you compare the Dart Sportsman to a stock Windor, there is a HUGE difference in stoutness, quality, and performance. As for machining, you want to machine it. That is the only way you will make sure your block is blueprinted correctly. I would never trust a mail order place to send me a short block ready for 400+hp. If you are going to play with 400+hp, it is time to stop thinging bolt-on and start thinking about getting your fabrication on.
For what it is worth, I really like the Dart Sportsman block. The only disadvantage I can see with it is if you want to run stock class drag racing. For that you need Ford branded stuff and may need year correct stuff. Since you are not racing that is not an issue.
< Message edited by urban_cowboy -- 5/8/2008 9:42:14 AM >
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