i was curious if anyone has tried boring out their stock cylinder walls to 83mm and using just a blockguard while boosting? i know it would be safer to sleeve my motor but since i've got a kid on the way, that wouldn't be an option. the motor it would be performed on would be a b18b.

 

Bad Idea.....
Blockguards are bad.
83mm wouldn't work on stock sleeves, If it did, it wouldn't work for long.

 

i think the most you can bore to safely is 81.5 w/ out any problems. Boring to 83 will not last long at all guarantee you will crack your sleeves. Block guard is junk in my opinion if not welded in. It will shift on you in the block. You can install it properly all you want but it will shift and you could end up deforming your cylinder walls.

 

 

I wouldn't even bore to 83mm on a stock block for all motor. I have never had a problem with my blockguard on my 81.5mm motor but mine is set in the block about 1/4 down and what holes line up with the holes in the head gasket well.

 

The only problems I have ever seen with block guards that are installed correctly are cooling problems. Even though that problem has been fixed in newer designs, people still knock em. Can someone show me some proof that a blockgaurd caused their motor to break? It just seems like someone said that they were junk one day, and everyone else agreed.....not saying anyone is wrong, but no one has ever been able to show me proof...

 

i know this is forced induction... but a buddy of mine has a b18c1 and is going ***** to the wall n/a. He has a darton sleeved block from his turbo days, whats the largest bore do you guys think he can go? 85mm?

 

I think 85mm would work fine on n/a with darton sleeves.

 

i think you can go 87mm all motor with golden eagle so you should be able to do the same with darton.

 

83mm on stock sleeves? Would there even be any sleeves left? I don't think so.

87mm sounds kinda outrageous also. I think 85 is closer to the limit, unless you arent talking street cars. I guess 86 or 87 is ok if its a serious race car where you dont mind breaking things. Someone me if I'm way off here.

 

someone told me they went to 84mm on a stock ls and boosted it. they are here on HT, but cant remember the name.

 

I *heard* (not fact) that the Golden eagle is 87mm and the Darton is good to 88mm all motor. Im probably wrong though.

 

is there any cooling problems related to this size? Also, what about headgasket sealing problems? thanks.