Does anyone have any experience w/ the GMPP 383 bare block (pn88959106)? It has a one-piece rear main seal, machined pan rails to clear the longer stroke, 4-inch bore, four-bolt mains, and machined for hydraulic lifters. Quoted price is $699. Seems like it would be an excellent foundation at a good price for a 383 rebuild.
Thanks!

 

It still needs bored .030 over. The GMpp 383 crate motor it comes from has a standard 350 4 inch bore and a longer stroke to make the 383 instead of the traditional 3.75 crank. I beleive they used a 3.85 or something stroke. But the motors would be a good SBC starting point.

 

Since this is in "LT1 Tech" I just want to make sure you realize that this block is not an LT1.

Rich Krause

 

I wonder why it's promoted in GM High-Tech Performance magazine when it's not an LT1 based block!?! According to the October, 2002 issue and the current issue, this block is identical to the 350 (although it did not say LT1 350). This is abit confusing. Sorry I posted a nonLT1 question in the LT1 Tech section...

 

I wasn't trying to be critical, just wanted to make sure you knew. AFAIK, GM hasn't been casting new LT1 blocks for a number of years. This may be a problem down the road.

Rich Krause

 

it's promoted in GM High tech because they arent limited to JUST LT1/LS1 cars. that would be great for 3rd gens or trucks etc.......

 

Whats different about the LT1 blocks? thanks
Jason

 

Mostly cooling passages for the reverse cooling.

 

ohhh. that makes sense. But the crank/rods/pistons are the same as a 86&up 1 piece block?