Using a 400 block, 4.155 bore with a 4.125 stroke is a 447. A 4.125 bore with a 4.25 stroke is a 454. 4.155 bore with a 4.25 stroke is a 461. Below is a site that sells cranks like these. You would also probably need a raised cam block like the dart iron eagle.

http://www.holley.com/types.asp?type=366

Adam

 

It takes a BIG pocket full of money.....

You need a Block that will have a bore of 4.250 .......( thats .125 over a stock 400 SBC block )

You need a stroker crankshaft.....that is 4 inch stroke......( that's a 1/4 of a inch MORE than a stock 400 SBC )

All of this stuff is after market......you can buy a turn key short block for about 5 grand or so.....and a complete engine for around 10 grand......

Bill Mitchell sells them......
http://www.theengineshop.com/

 

You can't do it with a stock block. You need an aftermarket block that can handle the large bore and stroke. Most are built up from a 4.125 or so stroke, as was the way I did mine. This keeps the bore size safe for future refresh. A 4.250 stroke can be done but a lot more grinding on the end rails even though they are spread.

The cost to build is not really any different than building up any 400 based engine from an aftermarket block.

 

The best compromised 454 sbc in my opinion would be a 4.185" bore aftermarket block (60 thou over 400 bore size) and a 4.125" stroke crank. Most aftermarket blocks can safely take up to a 4.2" bore.

 

there is small blocks up to 483 but for a complete engine they are about 28-29,000 is the going rate.


a good high torque combo would be a 434 with e-tec 200 heads,air gap and the comp 4x4 cam

 

actually back before we had the aftermarket blocks and such at our desposal it required
4.126 x 4.00=427
4.126 x 4.250=454
4.156 x 4.250=462
4.186 x 4.250=468
4.186 x 4.40=484 the cranks would come from hank the crank or moldex.the book also mentions that it would take a wheel barrel full of money also