Thread: Building a blown 402/427

Tweet

Recently a nice original BBC 396 .030 over block fell into my lap.
I'd like to build a blown engine..but don't want to bore the block out to maximum specs if I can avoid it.
I really could use some help choosing pistons and cylinder heads.
Piston choices are slim unless I build a 454..which means boring to the max and hoping the cylinder walls can take the abuse.
Most guys tell me to sell the block and build a 454..I'd like to build what I have.
Anyone good with numbers and can tell me what dome size of piston I'll need when bolting on 454 heads to a 402/427 bore?
I intend on using all forged parts in the bottom end and run this car on the street in a 1971 LeMans.
The Dyers Roots type blower will be added later.
Thanks.

i build many bbc for street/ strip and any thing you can put one in . i have over 20 bbc core blocks to build from in stock at my machine shop . there many 396 /402 pistons to pick from if you use the open chamber head the KB icon line is a good way to go .you really can not bore a 396 to 4.250 less a very early block and that will only get you to a 427 .less you use a4.000 454 crank. far better to start with a 454 block and crank if you want a 454

The numbers I see don't make sense..just a few examples..

Icon Forged Racing Pistons
Clicking on the pistons show a stroke of 4.0..my stroke is 3.766.

http://www.flatlanderracing.com/trwc...27.html..shows a bore of 4.250..should be 4.125.

Thanks for the reply.

sell your 396 to someone that needs a correct date code for an restoration and build up a 454 based engine--all the good stuff is gone from the shelves for the 3.76 strko packages and anything you do will need custom parts running the price way up---pick a shelf item parts combo and sell the 396

http://www.ohiocrank.com/chevybb_cranks.html..Crank $569

Ohio Crankshaft 6.135 rods $409

The only part holding me back is the pistons..looks like rock auto has the
SEALED POWER WL2383F..which run about $107 each..just a little high but must just work for what I want.

Thanks.

you have to call them they make them in icon but may show up under FHR series i have used them..my icon book at the shop .. i get them way less then $107. each same with the stuff you price out as i really do not care to just sell parts only. mostly for jobs in my shop .i carry all most every ones pistons jerry c may help you on just parts

Originally Posted by Louey

Don't feel bad, mine were 1150.00 this time. But, they were the ones I wanted, and needed.

i am a dealer for diamond pistons and others thats about the price for just a plain custom no trick stuff in a set of 8 with no pins . last set was about that for a 4.612 bore with a small dome and hell fire rings not that bad . i just did a big HD bike engine 4.155 bore JE pistons were over 650. for two pistons