how much hp before boxing frame?

[okyankee]

i got a 67 chevy swb and want to put a stock 572 in it. can the frame handle that or do i need to stiffen it up first? thanks for the info, kenny.

[mud.man.rj]

You may not need to but it will help in the transfer of power with less lost in frame twist and flex, why not use all the power your paying for. That also goes for rubber motor mounts.

[okyankee]

Originally Posted by mud.man.rj

You may not need to but it will help in the transfer of power with less lost in frame twist and flex, why not use all the power your paying for. That also goes for rubber motor mounts.

cool. thanks. i was thinking it wont hurt since i am sure i would have to tinker with the 572 sometime.

[mud.man.rj]

When you have something cool like a 572 how could you not want to toy with it sometime. I even chain my engine on the drivers side, just leave 3/4 to 1" play in it so the motor mounts flex a bit but not to tight so all the pressure is on chain. Definetly helps send the power back where it belongs not in the swing of the engine to the right. We mudrace a lot and rock crawl so on an off the throttle hard at times. Boxed my frame totally front to back on an 81 Cj7 that I had with a built 360 AMC with 39" Swampers, sure went straighter after the frame box, way less steering to the left just straight ahead. Power sure is fun, nothing, I mean nothing like Big block torque. Here is a pic of my last Racer a 79 Bronco. Loved it big time 460 torque, still like my 71 Gmc better.

[leftybass209]

I remember Stacey David saying when he built copperhead that that stuff wasn't necessary because these trucks came with a big block factory. He put a large 572 or something of the sort in it with stock suspension components. That's not to say the truck couldn't benefit from boxing the frame though. I guess its all personal preference and how hard you plan on beating it up! With enough horsepower your truck WILL find a weak link somewhere.
Posted via Mobile Device

[mud.man.rj]

His stock suspension components were aftermarket stock though. I know you don't have to as mine is only chained so far but with my 454 being over 500hp I know things will twist a bit eventually so I will do some boxing as I know the difference from the Jeep build a long time ago and plan on abusing my 71 as I do everything, got to use the Hp.