Alright, so i'm going to definitely keep the stock 4.3L block then. Now i am looking at getting between 250 and 300 hp. As far as i know a new stock engine is supposed to have 195 hp so this shouldn't be too hard. What are some ideas to bring it up to that 250-300 mark?

 

i got a few ideas. a new cam is gonna help out. if you get the block bored out and put in a set of oversized pistons. like i said dont go to crazy. other guys on here got more experience in this than i do

 

new cam is a for sure, but if i were to overbore the cylinder, how much can you do it by? ive heard some people bore them out by .030 i think but not positive...suggestions?

 

i dont know on the bore size. i could guess but i dont think you want the guy on the machine guessin either so ill keep my mouth shut. im sure some guys on here have done this. i'd ask swartlkk he might know someone that has. he's knows his stuff.

 

alright thank you

 

A 75 or 100 shot of nitrous would do the trick


Good luck with the rebuild..I think itd be a fun project! You might also want to consider picking up a newer 4.3 block with less wear and mileage on it. Then do the rebuild. That would also let you get working on the project with the block on a stand while still having the blazer as a working vehicle. That'd be my route for sure.

 

Hmm any idea how much I could get a new block for?

 

i'm 99.9% sure you can go .060 on the bore, but i could swear some one told me you could go .090 (depending on the year of the block).

and from experience, i'd stay away from doing anthing on the stock crank, other than polishing & chamfering it. even going "10/10" caused my first one to fail (snap).

if you're looking @ building serious reliable power from it, think aluminum heads, free flowing exhaust, upgrade your aluminum intake. here are a few places you can get some more info on building the 4.3;

How to squeeze 500hp from a 4.3L

performance crank kits

info found right here on BF!

Summit also sells a LB4 long block for 2 grand i think.

just some places to start looking. smart idea to start getting your game plan going now.

 

wow thanks for all the info ill check it all out and probably be up with more questions soon, its a 2001 engine so if you know the bore spec on that post it up otherwise ill stick with the .060

 

thats a good idea that way your not rushing to get it done