Alex72cutty

My Stock 350 is in need of an rebuild due to oil on #1 & #8 spark plugs and I was wondering if I could use the orginal block and just buy an 383 stroker kit for my cutlass? I was hoping to get advice etc. Or see if someone has done this in the past

lemoldsnut

Sounds like you have Chevy on the brain. Not Olds. What you build needs to match what your needs are. A 350 Olds can be built nice. I am sure lots of guys can help you on here. I don't think you can make a 383 stroker out of a 350 Olds to do that to a Chevy you bore it 60 over and use a 400 Crank. Olds Cranks are not the same to do that.

Alex72cutty

Aww... ok. I figure that. I kept seeing chevy pop up when I did the search. Thanks!!!

orange442

Actually a .030 overbore Chevy 350 with the 3.75 stroke 400 crank is the classic "383". So basically you could do it with an Olds 350 with less stroke because of its larger bore. If you could get a 3.7" stroke crank for the 350 Olds with its standard 4.057 bore, you would have a 383.

svnt442

If you want to know about stroking a 350 olds you might want to contact this guy. He ran a 380 cube motor (hence his name) for a long time until he went ***** out and did the 425 SBO DX block build.
https://classicoldsmobile.com/forums...all-block.html

Alex72cutty

Ok. Thanks guys!!!

kitfoxdave

CutlassEFI built my 380 stroker...

Alex72cutty

How did it turn out?

boese1978

I am in the "almost done" phase of stroking my 350 with Cutlassefi's (Mark ) help. Bored out to 4.155 crank offset ground, Icon Pistons, scat rods, Pro Comp Alu. heads with upgraded springs for a roller set up. Ask Mark he is a great guy to work with and very helpful.

s i 442

Good luck and I would say at the end of the day you will end up with a .030 Olds 350 and thats it.

380 Racer

I don't understand this statement.......please explain.

boese1978

I'd like to hear your explanation too....

kitfoxdave

I went fairly mild for a long distance cruiser about 9:1 compression (89 octane pump gas), dyno results were 320 HP, and 398 ft-lbs torque

Octania

I took that to mean that when you evaluate the cost of a 380 build vs. easy thirty over three fifty... unless your needs are great and your wallet too fat, the 355 looks like a great easy simple choice.

Me, I recommend you use a 4A or 4B block and 4-5-6-7-7a heads.
Kind of hard to find, but not that bad. I am pretty happy with mine.

380 Racer

I've said it before and I'll say it again........a tamed down version of my 380 would be awesome on the street. Talk to Mark and he can set you up with less expensive parts to make it affordable. 3.5-3.6 is all you can get out of a crank (again SBO). You can't get a 3.7 stroke out of a SBO crank without welding on the rod journals. I personally like 2.5" mains for less bearing speed, that is also what I have in my 425. Building a 380 doesn't have to break the bank and still have great power.

PM me if you like.

cutlassefi

I couldn't disagree more. The only "added" expense is having the crank offset ground. Otherwise the rods and pistons won't cost anymore, sometimes less, than replacing/reconditioning the original stuff with quality pieces.

Plus you can do little more cam etc. because of the added cubes etc. Until someone comes out with a lighter, stronger aftermarket SBO rod and more good quality piston choices, imo it's win-win no matter how you look at it.
Case in point, I'm doing an H-beamed 455 with a forged piston. The balance bobweight is 2259grams. The bobweight on my Speed Pro pistoned, stock rodded 350 was 2248, for a small block! The last 380 I did had a bobweight of under 1900grams, that's always a good thing. See what I mean?

s i 442

Really?
Well first of all he is rebuilding from stock, so unless he is going to drag race, after he sees the price and work it takes to build anything other than a .030 350 that will be the end result.

380 Racer

Read the above posts by Mark and myself ^^^^^^^^^^.

cutlassefi

Again not sure I agree with that;

R&R pistons from stock rods $40.00min
New forged pistons $400.00
Cheap cast pistons $300.00
Recon rods $120.00
Rod bolts $ 50.00

So add the total cost of all rod work, $210.00. You can buy lighter, stronger Eagle or Scat SBC rods for that.
Pistons - you can get some good Hypereutectic pistons for a SBC to work with the SBC rods for under $300.00, with rings.
My guy gets another $100.00 to offset ground the crank. Add it all up, it's less than a few hundred dollars more. Everything from here on out is the same as a stock rebuild.

A win-win in my book. Jmo.

rhett838

Horsepower Got 375 hp out of a 350 olds. They list the parts you need and everything...just an option. I think it was bored .30 over and they ground down the crank some.

You can watch the episode and see the parts they used clicking the link below. I watch it all the time b/c I have a 350 too. If anything it gives you some ideas.

http://www.powerblocktv.com/episodes...-for-new-power

M-14

Olds made a stroker 350, it called a 455.

61reoldsman

Another option is to find a 403 and build that up.

joe_padavano

Of course, the 403 uses the same 3.385" stroke as the 350 (and every other SBO), so technically, it's not a "stroker" motor...

wild70

not sure but what about a SBC crank with 2 in journal, that's if we are stepping outside of the block, suppose to allow for stroker with other goodies of course.

61reoldsman

Technically no it's not a stroker but in reality it is 53 cu.in bigger than a 350 and 400 cu.in is harder to get from a 350 even "IF" you stroked it.

svnt442

It's also 143 in³ larger than a 260, 96 in³ larger than a 307 and 73 in³ larger than a 330. It's still not a stroker....technically or otherwise.