angcobra

Okay guys, still trying to decide how to get out of the potentially breaking my 5.0 stock block.
What do yo think puts the most stress on the block, high torque output at lower RPMs or Higher HP at high RPMs?
Which is worse 563 ft-lbs (390 HP) @ 3,600 RPM or 440 ft-lb (563 HP) @ 6600 RPM?

waxyourboard

I'd have to go with... both.

Or if i had to pick one, the low end torque, as long as the engine is balanced. For some reason i'm thinking it would make higher cylinder pressures

Tims 88GT

no the thing that brakes the block is when you are pushing 500hp or tq and you rattle the tires or something and get the whole drivetrain to hop and that is shaking the motor and that is what is hard on the motor when you have a lot of hp.

FoxRod

Huh???? [&:]

I always under the impression that have a large amount of pressure that is needed to produce big power is what broke the motor. For example, like a lot of compression, blow by, things like that.

I do agree that a shaky drivetrain could definately complicate things and can't be good for things but not in the sense that he is thinking of.

JD1969

What happens is that the block itself deflects under load causing the crank/pistons/rods to bind. In a powerfull engine somthing has to give, in the case of the 5.0 the block splits. There are ways to help keep this from happening, main girdles help as does block fill, but it limits the streetability of the engine.

fastfox86

l

FullAuto

I made 567ft/lbs @ 3000rpm on a medium shot of nitrous and went quite a bit higher. It lasted over a year before I sold it. It's now in another car and still going strong. RPM kills the stock blocks, but at a certain power point, you'll break it even at 5000rpm or less.

StangStang

Yep RPM and 5.0 blocks dont agree, your block should be able to handle up to 500 hp before you have to worry, dont race it all the time if you dont have to, granny it around town and make people want to race you, than blow there doors off, shift into your powerband and love life!!!
Also if you blow a motor dont sweat it, get a junk yard block and build a engine to handle higher revs and hp. Have fun!!