383 Stroker

[potent rodent]

should have an 8 inch balancer and a balanced flywheel or flex plate

 

[Bennyt]

I wonder how much clearancing you'd have to do in order to stuff 6 inch rods in a 383. That would be so cool.
You have to clearance the web for 5.7s but it's only for two cylinders I think. (#2&5?)

It's not that bad. A few minutes with a die grinder. Takes more time to mock-up/ and take apart multiple times to check it.

I have 6" rods on my 447ci SBC but the block came cast already clearanced if I recall correctly and the camshaft location is raised as well which helps. I think guys that build the 480ci SBC's may have to clearance but I haven't been around really big displacement small blocks in years.

 

[potent rodent]

bennyt whats your set up

 

[Bennyt]

bennyt whats your set up

I have 2 different engines for my '63 Nova. A lot of different hands were involved in each and both were made with some parts/ processes you can't actually buy or are cost-prohibitive such as one-off billet heads or ported, polished, and flow tested water and oil passages. Both of these engines were built 20 years ago.

One is a 420ci based on a production 400 block that makes just under 1000hp on Nitrous. When I put it back in the car, I'll be switching to a twin centrifugal set-up and cranking it up.

The other is a 447tt sbc that I gave up on. GMPP Rocket block w/ billet 32v Arao/ Dominion heads. It made 1200+ on low, low boost. We were starting to turn up the boost when we had a valvetrain failure but I think it had potential for quite a bit more. That's been over 20 years ago and the long block has been sitting in storage since. The heads were one-off billet prototypes and the main engineer passed away at least ten years ago. It was more of an exercise on what could be built and not what should be built as the heads would probably exceed $30k alone.

 

[Buck69]

I wonder how much clearancing you'd have to do in order to stuff 6 inch rods in a 383. That would be so cool.
You have to clearance the web for 5.7s but it's only for two cylinders I think. (#2&5?)
The main journals of a 400 crank are bigger than the 350...they have to be enlarged. Whatever the word is..The machine work of the block is why they cost so much to build. Not providing a build sheet is very suspect...a guy would be wicked proud of it.

Now we're at the end of my 383 knowledge, (didn't take long) sorry I couldn't be more help. They are tire burning mothers though - ESPECIALLY in a pickup.
Gobs upon gobs of low end torque. That runs out of breath? Short rods?

Camshaft selection is critical.

The stroke (clearance required) is determined by the crankshaft throw. The length of the rod only reflects which piston to choose. The longer rods use pistons with a higher wrist pin location.

 

[Ricko1966]

You turn the 400 crank down to 350 main journal sizes. If you use 400 rods it'll go together with off the shelf 350 pistons. If you use 5.7 or 6 inch rods you have to get special pistons. All strokers I've clearance was just a bunch of trial and error put the crank in it put the pistons and rods in it with no rings start turning the engine. I use an artist brush and red paint,paint everything that hits. Take it apart grind all the red spots,put it back together repeat until you no longer hit anywhere. Now put the cam in because you're probably going to hit the cam in a couple spots,so you have to clearance the cam. If you buy stroker rods you won't have to clearance as much.

 

[Buck69]

You turn the 400 crank down to 350 main journal sizes. If you use 400 rods it'll go together with off the shelf 350 pistons. If you use 5.7 or 6 inch rods you have to get special pistons. All strokers I've clearance was just a bunch of trial and error put the crank in it put the pistons and rods in it with no rings start turning the engine. I use an artist brush and red paint,paint everything that hits. Take it apart grind all the red spots,put it back together repeat until you no longer hit anywhere. Now put the cam in because you're probably going to hit the cam in a couple spots,so you have to clearance the cam. If you buy stroker rods you won't have to clearance as much.

What would you recommend for a good block to start with?
I have an original 4 bolt, 10243880 rollercam block along with set of vortec heads I will be building next winter. Have been looking into stroking it with a scat rotating assembly.

 

[Bennyt]

The stroke (clearance required) is determined by the crankshaft throw. The length of the rod only reflects which piston to choose. The longer rods use pistons with a higher wrist pin location.

Yes, but a 6" rod requires more clearance than a 5.7" or 5.565".

 

[Bennyt]

You turn the 400 crank down to 350 main journal sizes. If you use 400 rods it'll go together with off the shelf 350 pistons. If you use 5.7 or 6 inch rods you have to get special pistons. All strokers I've clearance was just a bunch of trial and error put the crank in it put the pistons and rods in it with no rings start turning the engine. I use an artist brush and red paint,paint everything that hits. Take it apart grind all the red spots,put it back together repeat until you no longer hit anywhere. Now put the cam in because you're probably going to hit the cam in a couple spots,so you have to clearance the cam. If you buy stroker rods you won't have to clearance as much.

Clearance the cam? Are you referring to grinding the bolts?

A small base circle cam or a block with raised cam location solves this issue.

 

[Rusty Nail]

Ugh.
I know WAY TOO MUCH about 382.6s now and I have even less interest than I used to , which wasn't much.

6 inch rods put the wrist pin too high - almost. Yawn. 1.33
Then them motors run into camshaft clearancing issues? Turn me off like a switch. That's not sexy.

Here's damned near everything a boy could want to know about 383s.

Low cylinder pressure at slow engine speeds with bad camshaft pick.
1,2,5 and 8.
They make cheap ass aftermarket cranks for a 1 piece RMS block now even.

gag me with a spoon :vomit:

I dont know why but it doesn't appeal to me.
Moving on!

383 Stroker Small Block Chevy - Car Craft Magazine

A 383 Stroker Small Block Chevy is analyzed, assembled and dynoed. Follow along and get every fact and trick you wanted to know about a 383 build. - Car Craft Magazine

www.motortrend.com

 

[SquareRoot]

Ugh.
I know WAY TOO MUCH about 382.6s now and I have even less interest than I used to , which wasn't much.

6 inch rods put the wrist pin too high - almost. Yawn. 1.33
Then them motors run into camshaft clearancing issues? Turn me off like a switch. That's not sexy.

Here's damned near everything a boy could want to know about 383s.

Low cylinder pressure at slow engine speeds with bad camshaft pick.
1,2,5 and 8.
They make cheap ass aftermarket cranks for a 1 piece RMS block now even.

gag me with a spoon :vomit:

I dont know why but it doesn't appeal to me.
Moving on!

383 Stroker Small Block Chevy - Car Craft Magazine

A 383 Stroker Small Block Chevy is analyzed, assembled and dynoed. Follow along and get every fact and trick you wanted to know about a 383 build. - Car Craft Magazine

www.motortrend.com

Agree! And now they threw Vortec heads in the equation. Gag me with a spork! Ughhh

 

[Buck69]

Hmm... To each their own I guess?
For a capable person building their own sbc, why wouldn't you bump it up for a few more $$?
I went with a .020 over 5.7 on my last build. This second engine is just sitting in the shadows waiting for some attention.
I am referring to a relatively mild truck stroker build that will likely never see north of 5000 rpm.

 

[Ricko1966]

@Buck69 only reason I did any of them was stupid,stupid low pricing. I had 1/2 the junk laying around and didnt choose anything. 2 were blown up short rod engines so,1 was have a crank turned, a set of factory rods I had nothing in reuse the cam from the other block,# 2 crank was 2 hurt so had it ground to 2 inch journals,used early 5.7 rods clearance a block, free rods again. Number 3 somebody bailing out on their plan,short rods and crank I think I gave 100 bucks. Last I gave 150 whole longblock,someone bailed out on their project. I did intake exhaust and ignition, that was it. Wouldn't do it again,or then,unless dirt cheap stuff fell out of the sky and hit me.I built 4 stroker for the price of 1 stock rebuild. Yes the low end torque is great. But if I personally had to buy parts a normally prices,bang for the buck I'd build a 454. If I just had to stay small block I'd build a 406. My .02 cents. You can make more torque and horsepower with the 454 for similar money and never even turn the 454 hard to do it.

 

[Buck69]

@Ricko1966 All good! The block I have and the heads are hr'd out and owe me nothing.
The problem I have with my location is everything has to be shipped out. In my mind, the cost to have a magnaflux and grind done on the crank, along with new pistons, could go a long way toward a complete rotary group.
My truck has 4.56 gears. I would like lots of torque for pulling heavy loads but am concerned spinning a big block at higher rpm's will be a lot more thirsty than a sb.
I was offered a 454 by a customer a couple weeks ago out of an '86 2500 (same year as mine). He is going with a crate 502 in his truck. It didn't look like anything special to me though and has been sitting out in the weather for a while. I politely passed but it is still sitting there.
Will add, taking freebees from customers can get costly. I built 2 diesel engines for him in the past year and do all the technical diagnostics on his equipment. Don't like going down that avenue.

 

[Ricko1966]

Let's do some real simple math. To get 400 hp and 400 ftlb out of a 383 I am going to have to make more than 1hp and 1ftlb per cubic inch. To get 400hp and 400ftlb from a 454 I'm going to have to make less than 1 hp/ftlb per cid. You don't have to do much to a 454 to make more than you will with a 383,and it wont have to work as hard. Demon engines 454 was a peanut port,3angle valve job 454 with a baby cam,and a dual plane . There's a reason I've got 2 454s sitting here for certain projects.