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4.8 into a 383

1075 Views 12 Replies 6 Participants Last post by  BostonFan
Can these blocks be bored out to a 383. what are my options with cranks, rods and pistons do ls1 parts fit the 4.8 block. thanks for the help:bowtie: if anyone could make me a list of all the parts I need it would be real cool:D
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What? No.

A 383 is a 350 production block with a 400 production crank. The crank has some special machine work done, namely the main journals of the 400 are 2.65" and the 350's are 2.45" so they must be turned down by .200" to make the STD. 350 main bearing size. Since the 400 is externally balanced you will need a balancer and flywheel/flexplate for a 400 CID chevy motor.
werd I see. thanks 4 the info checkin out that link right now
nah, the most you'd want to do with the 4.8 block is turn it into an iron 5.7 Liter:imo Personally, I'd skip the 4.8 and get a 6.0 (Lq4 or Lq9) block. You can either run the 6.0 (364ci) or can get a 4" crank and stroke it to a 408.
the biggest the 5.3/4.8 blocks can go to is 382ci... mine's going to end up as an iron 5.7 if I dont get a LS1 short block soon enough.
Thought a 3.9 x 4.0 stroke makes a 382... for a Gen III
there' abouts LOL.... there was a discussion on a while back about it... I cant remember the final bore/stroke #'s on it but it was 382ci in the end LOL...
werd I see cool. so i can use 5.7 ls1 parts on this same block? Do I need to get it bored out at a machine shop.
is it worth it to do this? or should i go turbo? I have alote of experience with turbos i had a civic turb a coupe of years ago so i can probably piece one out no problem. I have a 05 rcsb i love it but its still pretty fuckin heavy you know. Im wondering what the cheapest route to get this HO haulin some ass like 13's. give me your input im all ears. Thanks for ur helping
If you want only 13s, just swap in a 5.7 long block with a good street cam.

You could always just boost the 4.8, it'd run strong then.
first all you want is 13's... then 12's... then 11's... LOL... its a deadly cycle
first all you want is 13's... then 12's... then 11's... LOL... its a deadly cycle
BIG :word:
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