High Compression N/A with over bore

RainyP71

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Hey everyone,

Not an engine building expert so wanted to ask some advice. Doing a budget build and have some random parts

I've got a cobra iron block that needs to go to 0.0020/30 over. I was wanting to do a higher compression N/A build, possibly low boost in the future. Using h beam rods, forged crank.

I was wondering, if I'm doing 10.5:1 of higher, will I be okay at 30 thou over using Cometic C5118-040 head gaskets and arp 8740 head studs? Need to figure out if I need to buy another block or other supporting parts.

Thanks!

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01yellercobra

AKA slo984now
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I think the iron blocks can handle a bit more of an overbore. Is sonic checking still a thing? I remember it being mentioned a lot back when I played with carbs and push rods.

I ran those kind of head studs on a big bore iron block with boost and didn't have any problems. I used Cometic gaskets as well.

Personally I think you'll be ok. Just have the block looked over before committing to anything.
 

Blkkbgt

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The land of commies and socialists!
Hey everyone,

Not an engine building expert so wanted to ask some advice. Doing a budget build and have some random parts

I've got a cobra iron block that needs to go to 0.0020/30 over. I was wanting to do a higher compression N/A build, possibly low boost in the future. Using h beam rods, forged crank.

I was wondering, if I'm doing 10.5:1 of higher, will I be okay at 30 thou over using Cometic C5118-040 head gaskets and arp 8740 head studs? Need to figure out if I need to buy another block or other supporting parts.

Thanks!

Sent from my SM-G975U using Tapatalk

Why does the block NEED a .020 or .030 over bore?

Does it have damage cylinders or is this what your machine shop is telling you?
 

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