Does a brand new GM block require machining at all? I'm wondering if the cost of a new block would cancel out the cost of machine work+cleaning/prep+core charge. A new 4-bolt, 87-up, 1-pc RMS goes for around $600. What do you guys think?

Thanks,
Larry

 

depends what you want to do with it.. but for a basic build up it shouldnt require machining

 

I just bought a ProCharger D-1 supercharger kit for the malibu in my sig. I tore down the motor this week, and it's only a 2-bolt, stock rods, crank, and pistons, and it has already been bored .040, so there really isn't anything I can reuse. Now I need to build a short block to handle the blower, and I'd like to stay with a newer style block so I can use an oem-type roller cam. I plan to use a stock stroke Eagle forged crank and 6" H-beam rods, and SRP blower pistons. I'd like to keep the whole assembled short block under $3000.

 

Ok, yes you will need to have the block machined because there is a lot of places where even an after market block needs to be optimized...such as oil passages, combustion chamber characteristics, air flow passages, and proper fluid movement (coolant). If you fully prep the block with supercharging in mind there shouldn't be any reason why you can't get about another 50-100hp out of your engine; as oppose to just putting it together as is. There are always benefits to be had from prep work...wether it be more power, longevity, or drivability. You'll probably find that anyone who says otherwise probably isn't getting the most out of thier engine. Just my $.02

 

Air flow passages and combustion chambers? He's talking about a block here.

 

i do believe they are already prepped and if anything may require just a hone. if someone is finding a combustion chamber in a small block chevy, they are looking at it wrong let alone finding airflow anything other than the bore.