BBC Gen VI block

How big of a bore do you think we can do without cracking?
This is about 1750 HP.
Do you think we can go 4.600"?

 

we run a dart iron block it is 4.600 and we are starting to get cracks right where the studs go in the block but we are making over 2200 hp my engine guy said it is pretty common for these to crack at the stud boss hope this helps

 

I'm Fixin to do mine at 4.600 as well about 2k hp mid screw deal. I figure its the last bore it has left for that hp I hope it holds was thinkin about turnin it up. We'll find out next season.

 

I found the o-rings to be difficult to put in a 4.6 bore, not a lot of material between the cylinders. Just my opinion.

 

Are you filling these water jackets with a block filler?

 

I have also been advised that O rings are an issue at 4.6, you may be better of using the multi layer gaskets rather than copper (Cometic's are one brand I think) Cheers

 

My O-rings are a figure 8 pattern

 

orings r not no problem in our block at 4.600 big chief heads i also run 540 bbc 2000 hp range 1471 hh 33 over with the new copper gasket with internel ring have had very good luck with it

 

Hi rawolton, do you have standard BB Chevy bore spacing in your beast?

 

Please talk more about this gasket, website, etc

 

4.6 bore

My last engine was a bowtie chevy with a 4.6 bore, it broke a piston pin. When i toke the engine apart afterwards (block was destroyed) i noticed that it had cracks in the bores close to the headstuds. I have since gone to a hemi, but if I ever where to run a BBC again i would never go to a 4.6 bore after seeing this. The last pic shows how thin the cylinder wall is, don't be fooled by it it broke at an angle so it looks thicker than it was. Yes i know many people run chevys with 4.6 bores and yes we probably did alot of things wrong. these are just my personal experiences.

 

the gasket is called ics copper head gasket you can purchase them from many places good vibrations motorsports have them jegs summit ect some also call oring gasket i have had good luck so far hope this helps thanks and yes have standard bbc dart big m block 540 12.1 1471 hh 33 % over

 

Which block are you running, Gen VI (6)?