dose any one have any info on how to make a 383 stroker.

 

do a search. you will find tons of 383 info. as well as other strokers, intake setups, cam selection, and whatnot.

383 stroker uses a 3.75 inch stroke with a .030" overbore. .040 over is a 385 and .060 is a 388. standard bore is a 377.

many kits available for 383 strokers like eagle, motown, and summit racing, etc. or piece one together with a crank and get rods/pistons to go with it.

 

2 ways:

0.030" bored 400 block with 350 crank

or

0.030" bored 350 block with 400 crank (most common)

 

Don't give wrong information.

A 400 bored .030 with a 350 crank only makes a 377

The 350 (or any 4" bore block) bored out .030 and using a 400's stroke crank makes a 383. The 400 crank will not fit into a 350 block without having the mains turned down.

Same goes for the 350 crank in a 400 block. It won't fit unless bearing spacers are used.

 

The latter of Adam's wasn't wrong. It just wasn't completly accurate.

Don't forget clearances. Need to check all the appropriate areas so the counterweights clear. Rod to cam clearance too.

 

By 400 crank, I meant a 3.75" stroke crank... same as in a 400.

I just did the math on the .030 400 block/350 crank "383" and you were right, its a 377, not a 383. My bad, I stand corrected.

 

.060 over on 400 block with 3.48 inch is 383 LOL

 

I wouldn't destroke a 400 block though....

 

I wouldn't either. That would be giving up the 400's greatest asset, torque. But I've read that 377's make great drag race engines, like a 302 Z28 engine with 75 extra cubic inches. It's also a really popular circle track engine.

For the street though, I wouldn't destroke a 400 either. I'm not sure I'd stroke a 400 either though...at least not unless I had a good Bow Tie block. I've heard of 400's being stroked to 454 cubic inches. Wow.

You really start getting some very bad rod/stroke ratios when you put a 4" crank in a 400 with short rods!

 

when you say rod/stroke ratio, whats a good ratio to have? does a 383 with 5.7 rods have a good ratio?

 

IIRC, the closer the ratio is to 2, the better. IE - a long rod, short stroke engine (ex. 302, 6" rod) will be closer to 2 than a long stroke, short rod engine (ex. 400, 5.7" rods)

 

by closer to 2 you mean take the rod length and devide by the stroke length? ie: 302 and 6 inch rod = 6"/3"?

5.7/3.75=1.52
5.7/3.48=1.64ish
why does it make it better?

 

Exactly.

A rod/stroke ratio of 1.60 or better is not bad. A 400 engine with 6 inch rods will give you 1.6 R/S ratio. But it's only 1.52 on 5.7" rods. A 350 Chevy has an R/S ratio of 1.637. A 427 big block is 1.629. A 454 is 1.53, which isn't very good.

You start getting interesting rod to stroke ratios with the following engines:

377 (destroked 400)= 1.72 (6" rods)
327= 1.75
302/283 = 1.9

Some of the stroker engines, such as 350-based 396's and 400-based 454's have miserable rod/stroke ratios way below 1.50.

What this means is that the piston speeds approach critical at much lower rpms. This limits hp, since rpms are directly proportional to hp. And also probably limits lifespan.

Besides that, small block heads just don't breathe well enough for big block sized displacements at high rpm.

Things to consider.

 

Taking a production 400 block out .060" is scary. I don't think there would be much cylinder wall left after that. A 454 SBC doesn't use a production block.

I've seen a few 377's at the track.I pit with a 69 Camaro that runs one and he runs low 11's with it.

As for rod/stroke. My BBC uses 1/4" longer rods with the standard 4" stroke. I use special pistons. If for any reason I decided to go with a stroker crank, I could reuse the rods but would need new pistons.

I played with Dyno2000 and installing a stroker crank would make a lot more torque in my engine but HP wouldn't change much. I already have more torque than I need.

On the other end of the scale my old 383 stroker used stock 400 short rods for a terrible rod/stroke ratio but it was enough to produce about 450-500 hp and run high 11's. The car was much heavier then.

 

Interesting.

A book I read on Corvettes talked about the comparison between 427's and 454's. An engineer for GM mentioned that the additional stroke of a 454 didn't provide any additional horsepower, even though it increased torque.

The 427 I run in my Corvette is actually a 454 4-bolt block that I destroked to 427 cubes. I'll be doing a lot of open road racing with it, which is why I wanted the 427 in it.

...One potential problem I didn't think of is fuel economy. Would a 20 gallon gas tank last me 100 miles at 140+ mph average? Only if I can pull off better than 10 mpg. That'll be interesting.

Maybe racing would have been simpler if I did like you did and stuck to drag racing.

BTW, how much compression do you run? And what kind of cam profile do you have? What kind of octane do you require?

 

13:1 compression.
Roller camshaft is new for 2005. .740/.740 lift. Duration is 274/278 @ .050.
I use methynol alcohol as fuel so octane isn't a factor.

Bore makes HP. Stroke makes torque. 427/454/496 all use a 4.250 bore but stroke is different for each.

Making a 540 with a 4.5" bore and 4.250 stroke make more HP and torque. GM's new 572 is nice but a 632 is the ultimate.

 

So getting back to the 383.

The 383 will make more torque than a 350 but roughly the same HP.

A 377 will make the same HP as a 400 but less torque.

The 400 will make more HP and torque than a 350.

That's assuming everything else is equal. Bigger engines can use more camshaft and also should have bigger heads to feed the engine.

 

That's a good rule of thumb, but the ability to hit higher rpm's give it the ability to run a bigger cam.

For example, with the right parts and a big enough cam, a 377 with a 1.72 rod/stroke ratio (6" rods), will outpower a 400 at 8000 rpm, since the 400's lousy 1.44 rod/stroke ratio will never see anything close to 8000 rpm (using stock 400 rods).

So your rule of thumb I would say is a good guide considering "all else being equal". When you start changing variables like the cam, etc., is when you start straying from that rule of thumb.

 

ehh, why not just go with a Pat Musi 706? or a IHRA mountain motor prostock 800+cubes!

 

Won't fit unless I go to a complete tube chassis. I'm having a hard enough time getting the engine I have between the fenders.

 

gm makes crate 383's - HT383 it has a 4" bore and a 3.8" stroke to get to 383 cubes - about the same but different yet