Boring out a early model 396
 

How far can you bore out a early model 396 and still be safe.Do you need to fill it.The motor is going in a bracket car.


Thanks, Alan Warman L/SA 4103

.020 might be pushing it on an old block thats full of rust pits in the water jacket. ...... Even filled, the chance of a crack or pin hole is pretty great. .... If you've got your heart set on a 396 ,Find a cheap 454 block thats been race prepped and has worn out bores , and punch in 8 sleeves. .. Super Stock racers have been doing it for years. Illegal for Stock tho. .....Tom

If it's illegal for stock I know a bunch of people that are in trouble but most of them have been there before.
I've seen several 427s made out of 396's but it is not something I would want to do. I've never had anytrouble with .060 on a 396.
Pete

The motor is for the kid next door.I told him to go out and find a 454.But he already has two 396's.The motor is going in a truck (only in Tx) the local track as a truck class.


Thanks, Alan Warman L/SA 4103

Alan,
Call me.
Adger Smith
Shop 903-794-7223

Adger Smith

Years ago, I did several +.060 396's some lived , some cracked, ..lately ,most of the blocks that have come my way have sonic tested rather thin, probably due to excessive rusting of the water jackets. ... Probably your safe at .030, but I'd spend the money to sonic the block before spending any money on it. .... Tom

1965, 1966, 1967 396 blocks will usually make good power @ .060 to .070 over. 961, 962, and 406 are the last three numbers of these blocks. However, I have recently seen one of these 'thick' blocks split from excessive waterjacket rust. ANY of the other passenger 396 blocks will make more power @ standard bore size and will definitely last longer at this size.

Hey Tom... explain why 8 sleves is illegal in stock..

It's not illegal and the 2007 rulebook says "blocks may be sleeved" in Stock under engines. I doubt you'd see so many cars running as fast as they do with a lot of different engine combos without an 8 sleeved block. 396's were very poor, I soniced many blocks and 396's were generally very thin except for the early years.

Bub, I stand corrected. ... I believe at one time the rule for sleeves followed the 75% rule for valve seats., but I see there is no limitation anymore in the rule book. .... Tom. ....... Hey Rich , you going to Dinwiddie?