Gearhead442

Hey i have a 1983 350 diesel block laying around in the shed. I heard you can get 454 cubes out of one stroking the engine. Could you please give me a HP and Trq estimate of what i could get out of one and if its worth doing?

Olds64

I've also heard that you can machine a 350 DX block to get monster cubes; however, I doubt it would be worth it. The price would be exorbiant. You would be better off buying a 425 or 455 and dropping it into your project. It would be easier and cheaper in the long run.

Run to Rund

The diesel block has thicker cylinder walls and a lot more beef around the crank. For extreme racing, it is great, but expensive to get the benefits. The crank has to be custom machined from a forged 425 crank with the counterweights cut down, etc. to use the 3" mains on an otherwise small block crank setup. The beef makes it possible but still expensive to install custom 4 bolt main caps. Overall, for a mild buildup, or even 500 HP, just go with a conventional 350, 425, or 455.

bccan

I think for the most part to get that far you are looking at a bore around 4.2"+. Generally means cyl walls are gonna start getting thin which can negatively affect the bore integrity and therefore ring seal. At this bore I think you are frequently going to want a filled block to help stabilize everything - fine for the track, not street friendly as you are filling water jackets w/epoxy instead of coolant. Sonic test would reveal thickness & uniformity of walls & judgement could be used from there.

I don't know how much stroke you can gain from offset grinding a 425 crank but 4" is easy and I believe more is possible. I'm building one now that will be 4" stroke x 4.155" bore for 434 ci. This seems to be a pretty common combo.

There is a lot to consider on a stroker build and general wisdom says that unless you are married to a small block, build a big block if it is displacement you're after. Considerably cheaper. I however have married the small block & am headed that way. I am finding that DX doesn't necessarily have to be a money pit & some of the extra machine work gets offset by using off the shelf Chevy/Ford internals & dimensions. Crank work & balancing are 2 main areas where extra $$ needs to be spent over what a "normal" build would cost. Rods, pistons etc must be carefully thought out or ideally go to a custom piston. I think I'll be pushing $5k for the short block on a conservative build - $2k in parts, $3k in machine work while reusing what I can from present engine(hyd roller cam/lifters, timing cover, etc). If my cam is too small, there goes another $500. Cam will be the last thing considered.

Power handling is largely limited by your combo & bank account - how much do you want to spend on strengthening, light recip assy, compression, etc. Power is in the heads, cam and often power adder. Power adders seem to be the best application for these as in turbo/supercharging or huge nitrous because blocks are quite strong. There are people making tremendous HP, say 700 & up w/reliability at the upper ends of the Olds racing world and many of them are not necessarily big displacement. I think general wisdom says that Olds cranks are only going to hold up to 600-700 hp range so a properly prepared block can take you well beyond what factory parts can. Don't know how much it costs to start getting into those ranges and never will!

Destructor

Build it as a deisel, pull in front of hybrids and stink those F's out.

380 Racer

Why mess with a D/DX if you aren't going to race it? It takes many $$$$$$ to make anything handle 6-700 HP reliably for too long. I would never take a 40+ yr old crank, whittle on it and expect it to take alot of abuse.
Dropping in a BB is not a fix all answer. I chose a SB over a BB for many reasons. Oiling is not a worry in a SB, main cap walking & crank flexing don't pose many problems either with the SB. Plus more.

By the way my 70 Supreme (3300 lbs) with it's 425 SB ran a 9.68 the last day of the season. But to each his own.

KRICHEN922

Block...that comes with a dieslel engine? I have decided to buy a new engine instead of fixing up mine. My mechanic friend said it would be like doing open heart surgery upsidown and without a scalpel.... so if you got the engine I'll buy it...