I posted this in Tech forum but got no responses yet.

I would like to find a source for a good 'direct replacement', assembled, short-block to replace my L48. During my last rebuild, I bored the block .020 over, turned the crank .020 under and I now have oil control problems. During a recent cyl head removal, I found some cylinder scoring in the #8 cylinder. I've got a fair amount invested in replacement top-end parts (heads, intake, carb, etc.) and would like to purchase a good short block with the following configuration:

350-355 ci
stock dimensions on bearings (not turned)
flat-top hypereutectic pistons (with 4 valve reliefs)
powdered metal rods
cast or forged crank
right-hand dipstick

My preference is to move my top-end parts to the new short block.

Should I just get one of those new GM blocks and add a balanced rotating assembly? Perhaps buy one of the P.A.W. short block kits (but with my pistons of choice)? I'm not interested in a killer engine; just something capable of performance in the 325-335hp, 380-400tq at the crank range (something like what I have today but without the oil control problems).

I am not interested in either the 260 or 290hp Goodwrench engines as I believe they both have dished, cast pistons; I'd really like to go with the flat-top hypereutectics with valve reliefs to compliment my 72cc DART heads currently on my engine (keeping the compression close to 9:1 instead of 8.5:1). Otherwise, if compression were not a problem, I WOULD just buy one of those assembled Goodwrench engines, ditch the heads and add my top-end; all for under $1500 plus the price for a cherry picker, gaskets/seals, etc. Too bad GM doesn't offer such a short or long block with my preferred pistons in a Gen 1, right-hand block config...

I really want to stay away from the 'zz' offerings from GM Performance Parts. Also, I'd like an engine that isn't going to have deck surface clearance issues from having too much material removed from decking, align boring, and such. I just can't seem to find this combination (in a short block) from a reputable source.

I want to do something soon as I really don't drive the L48 much anymore due to my valvetrain noise and oil control problems.

The answer to my problem may be to just try to have the block bored to .030-.040, add a fresh, balanced rotating assembly (crank/rods/pistons), throw in a fresh rebuild kit from Northern Auto parts, and fix the valvetrain noise once and for all...

Suggestions welcome!

 

What the heck! I will give it a shot! Rebuilding your short block properly is your best position. You keep original engine in car instead of on the floor, been there done that! Build that L48 they way you want too! You can also buy a used 350 and build that. Some times engine builders are a good source for engines and blocks. Find a reputable engine builder, who can stand behind their work. I would ask others in the forum for engine builders in your area!