396 sbc?

[latemodelracer45]

Has anyone ran the 396 sbc combination (4.030 bore & 3.875 stroke) for dirt racing? Is it worth paying extra for the .125 stroke and machine work? Or, should I go with the 383 assembly?Also, will be running 500 cfm 2 bbl. at some tracks.Thanks!

[roundboy]

I have been kicking this around myself.. wondering about a light weight rotating 383 or standard weight 396.. my only concern with the 396 is the amout of material that is going to have to be removed and if it would affect the strength of a stock block.. also would be turning around 7500 rpm max...

[lilsumo]

Why not a 4 inch stroke crank

[racer11w]

I have had a 4 inch stroke in a stock 350 block. Its a lot of work to get the crank and rods to clearance, but it can happen. It was an awesome motor that was ran in a stock intake class. Won lots of races with it and its still being raced with no problems. Low rpm motor with lots of low end torque. I had to have custom pistons made for it that was $1200 and a small base cam.

[lilsumo]

you can run off the shelf pistons, just have to do what most guys are unthinkable. Run a ford 302 piston in a SBC

[Verdoorn Racing]

Icon lists a piston = http://www.cnc-motorsports.com/pisto...-030-bore.html.

Is it possible to use a 383 piston with a 5.85 or 6.125 rod?

[lilsumo]

What I did was run a 4 inch stroke crank, of course, and a set of 5.850 rods, with a set of 347 ford stroke pistons.

The pistons have a compression height of 1.175. That means the block you use has to be pretty good. The deck needs to be as tall as possible, like 9.025 to be perfect. Last one we did, we had to deck the block .015 and the piston stuck out of the hole .017. No biggie, just made it up with head gasket thickness.

Some people will tell you not to run any popup, but I disagree. Running the piston out of the hole is not a big deal, just have to watch the top ring doesn't come out.

This is using all off the shelf parts

[lilsumo]

Does anyone make a 4" stroke cast crankshaft?

[stock car driver]

What I did was run a 4 inch stroke crank, of course, and a set of 5.850 rods, with a set of 347 ford stroke pistons.

The pistons have a compression height of 1.175. That means the block you use has to be pretty good. The deck needs to be as tall as possible, like 9.025 to be perfect. Last one we did, we had to deck the block .015 and the piston stuck out of the hole .017. No biggie, just made it up with head gasket thickness.

Some people will tell you not to run any popup, but I disagree. Running the piston out of the hole is not a big deal, just have to watch the top ring doesn't come out.

This is using all off the shelf parts

Its 2014 lots of shelf pistons for any stroke any rod now.

[roundboy]

Thanks for the great info!! A 4 inch stroke crank is a idea, didnt think of that.. the b-mod class i run has a open motor rule, it just has to be steel heads, block, no roller cam and a 2-barrel.. i have a 377 now and it runs good, but always looking for more.. this is in a 4-bar car on UMP tires so it puts down everything i give it..

[stock car driver]

Why not built a 434 then, why are you thinking so small?

[js11]

Yes. I have seen the sbc 396 run in a dirt modified. It's a heck of a motor if built correctly.

[roundboy]

My only worry with something as big as a 434 is i can only cram so much air through a 500cfm 2-barrel and i need strait away speed as much as out of the corner umph which im sure with the correct gear i could get both.. and if i ever decide to go A-mod, i would like to know whatever i build will hold up to the abuse.. but, thats a BIG if...

[stock car driver]

ic 434 ran great for me with 4412, only turned 5500 when I won the Ice Bowl in 2011

[roundboy]

I would like to try a 434.. im sure it would be mighty impressive!!! Wonder what gear would work best on a 3/8 mile D-shaped clay oval with a 434 with a 4412?