nitrojunkie1029

I dont know much about engines but i know that a 383 stroker is a 350 with a 400 crank, but i wanted to know what would happen if you took an olds 350 and stuck a 455 crank in it. help would be greatly appreciated, thanks Dom

MDchanic

It wouldn't fit.

The bearing journals are different sizes (also the counterweights are too big).

Now, if you put a 455 crank in a Diesel 350 block, that'd be a different story...

- Eric

380 Racer

455 crank won't work........not enough room for the throws. 350 with a 400 crank is a Chevy motor.

cutlassefi

Correct, the only real way to stroke a gas sbo is to offset grind the crank.
However Procomp is supposed to be coming out with stroker sbo crank. Details are unknown at this time however.

nitrojunkie1029

oh damn that blows, can i still make a 383 stroker out of a sbo?

cutlassefi

Yes, offset grind the crank to 3.500 stroke, then bore the block to 4.185, that comes to 385 c.i.. or just bore it to 4.155 and that'll make a 380, i.e. 380 Racer.

I have a SBO block that's already bored to 4.155 ready to go laying in waiting for some sort of stroker crank. I'm hoping for a 3.75 stroke to get 406 c.i. That should make it fun!

joe_padavano

Why? There's nothing magic about a 383 cu in displacement. It's now common for Chebby motors due to the ease of dropping a 400 crank into a 350 block, but there's nothing special about it, just cheap for those building an SBC.

I've said this before, but the cheapest way to "stroke" a 350 Olds is to replace it with a 455 Olds...

380 Racer

I still think the 380 is a very good combination .

joe_padavano

And I certainly can't argue with results, but of course the best combo for the track is rarely the right one for the street, or vice-versa. It's like all the guys who see Powerglides in drag cars and think that's the trans they should be running in their street car.

nitrojunkie1029

i think a 406 sounds badass

nitrojunkie1029

is the 455 heavier than the 350?

captjim

It is a little bit taller, a little bit wider, and a little bit heavier.

joe_padavano

The difference is around 50 lbs, less if you use an aluminum intake.

compedgemarine

the main reason the chevy's get stroked to 383 is they make more torque and power than as a 350. that said in a chevy to go to the 454 means all new mounts, brackets, headers, etc, etc plus the 454 takes up a lot more space and weight. with the olds being the same external design it makes more sense to just go to the 455 since the only difference is in the height and width by a small amount.

nitrojunkie1029

so a 455 will bolt right into my car if i pull the 350?

SBORule

You can take a forged 425 BBO crank and have the counter weights cut down and have the rod journals turned down to 2.100" and run a 6" SBC rod with some custom Pistons and have the 3" mains turned down to 2.5" and it will fit in a gas 350 block. 3.98" 4/00" with a 4.100 to 4.125" bore amd have yourself a 427ci SBO.

It would be cheaper to put the 425 crank in a diesel block so you wouldn't have to have the main journals turned down to 2.5".

People talk about putting over 4" inch stroke cranks into a Diesel block but it really isn't practical because you run into the rods hitting the cam lobes.

427-428ci Small Block Olds is a better way to go than aiming for a 463ci SBO.

You could also put an above mentioned 425ci crank into a 403 gas block and make yourself a 480ci Small block Olds.

captjim

I am going to question a lot of this post. Can you cut .500 off the mains? Where do the oil holes end up being? Will everything clear the block? Will it be a balancing nightmare? Will the rods need to be longer than 6". Will the crank alone cost more than an entire 468 bottom end which will have 40 more cubes? Using a 403 block? Really??

joe_padavano

THANK YOU! Exactly my point. For a street motor, this is by far the most cost effective solution.

Redog

I've heard that if you take a 350 DX block, and covert it to gas it becomes a 411 stroker

Stick that in your tailpipe Chevy guys LOL

captjim

Is that a joke? Same bore, same stroke, same cubic inches.

olds 307 and 403

I'm pretty sure someone ground down a 425 crank, oil holes were way off. A 3.5" and 3.6" stroke are possible with stock crank. I'm going 424 ci with my 403, have the custom pistons, Scat sbc rods and just need my 330 crank off set ground. If 3 transmissions didn't fry this year, I may have started the build.

380 Racer

Yup I chuckled