Hey Fellas,
I'm planning on upgrading my heads to put me in the 550 hp range N/A at the crank. Im using stock main caps and main bolts in a 69 440 block. I want to be able to turn mid-high 11's in a 3,600 lb B-body.
It will only see the track a few times per year.. am I asking for trouble ?

I did it for years.

That being said, ARP main bolts are pretty cheap.

Thanks for the reply Fast68.Would it be OK swapping them in the car ? Or will new bolts necessitate a line bore/hone? I don't really wanna break the whole motor down just to swap out 10 bolts.

I've never had to adjust the line bore when using the bolts...... But I probably wouldn't bother installing them with the motor in the car.
Just wait til it's apart next time.

Ok.. cool. Thanks for the input. Much appreciated.

Make sure the tune up is safe

Absolutely.. thanks Cab.

My old 440 was dyno'd at 575hp @ 6,100, 545 lb.ft. @ 5,400. Ran forever with stock main caps and bolts. You shouldn't have any problems.

You SHOULD be ok

I would look at it like this:

Stock caps with stock bolts.... You SHOULD be ok but it might blast a piston out the side of the block.

Stock caps with line hone and main studs...... You are less likely to have a piston blast out the side of the block.

Aluminum caps with main studs....... The chances of anything going wrong are better that the 1st and 2nd options above.

Aluminum caps with a girdle....... The chances of a few on Moparts telling you the girdle does nothing is close to 100%. ... The chances of your engine surviving up to 600 or more horsepower with a girdle installed will be better than without...