I have recently been thinking up a little project for a spare 4.8L that's in the garage. I was thinking by using a 4.0" stroke crank and boring the 4.8L block from 3.780" to 3.820" (+.040") and using 6.125" rods, that I could achieve a 366 c.i. engine. I have seen a lot of people talking about how they are happy with their 370s and so fourth, but I have looked around and haven't seen anyone doing anything of this sort... except for making a 4.8L/5.3L to a 5.7L which requires .123" bore of the block to do so (thus making me think it might not be so boost friendly). I need some suggestions on this.

 

bump, I'd like to know also...

 

Same here BUMP!

 

TTT awsome idea i thought i was the only one who thought of that. it would be a tourqy SOB.

 

you can punch it out 40 over and have your 366.
or you can punch it out to the LS1 bore 3.893 to give you around 381ci with
room left over to keep your motor and punch it again to 3.905 to come
out around 383ci later down the road.

it will handle boost or nos very well.

 

will the 4" crank go in one of these smaller blocks without clearencing anything?? if so... I may be on the lookout

 

Yep, its been done. There's a few Iron block 383 running around out there.

 

hhhhmmmmm I guess I need to start looking for a little cranky shaft

 

Do you have to get a different oil pan for that crankshaft to clear or is there already enough clearance?

 

no all the blocks are the same.... i have my 4.8 and 6.0 sitting side by side and i measured them both and the only diffrence is bore/stroke. I can not find and other differences....