Hey guys. I know everybody likes strokers and big cubes ect. And I do too. I want to build a 400 with a turbo. I'm using a clean 400 block, a 383 crank, h beam rods, but I'm hung up on pistons. I need a forged slug around 9 to 1. Does anyone know of any? I've seen a lot of hypereutectic and cast, but not much on forged. Any help is appreciated. Thank you.

If you have a credit card you can get pistons, they are just a phone call away.

You might consider using a longer rod since then you won't need such a tall piston.

Would you not be money ahead to do a 451? Those parts are very common and ICON makes dished pistons.

I get what your saying Andy. What combination would you suggest?

I also thought about that too. I'm going price that out also. I'm also not opposed to good used parts. I'm always looking around. I just want something I haven't done before.

Diamond will usually give you one free change to off the shelf pistons. They sell a .035+ 400 piston that they can probably modify the compression height to bring compression down.

If you use a 1.32 CH piston with a -12.5cc dish and a factory iron head you would be around 9:1 with diamond shelf pistons.

This one might work too:

https://www.uempistons.com/index.php?mai...0c35ef4f98f6b6e

Of course this is all for a 451 i.e. 400 w/ a 400 journal sized 440 crank and a 6.76" (stock 440) rod.

I did a stock stroke 400 a long time ago with Hemi rods and shelf stock stroker pistons. That engine worked really well. Ran high 10's in a street car with full exhaust, full interior, street tires, etc.

Is it a must to have forged..I have a fresh low deck 400 stock build heads cut I'd like to turbo sometimes down the road ..got a holeset55 off a Cummins not looking to set the world on fire but to learn go from there ..turbo makes 400 and 1250 on Cummins..

Um, would you care to share all of the details of this?

Heads, cam, intake/carb, Converter, gears? Car weight?

Wow...

A shelf piston?

Ported RPM heads, Victor 383 intake, 750 DP carb, small Ultradyne solid roller. I don't recall the gears, probably 3.90 since it had a 8 3/4 rear end. It was a '72 Duster with full interior, full exhaust, street tires. Ran 10.90's a bunch of times until it was kicked off the track since he didn't have a roll bar.

Yes, a shelf piston fits just fine with the long rod. I think we used a piston with a CH of 1.32 and then decked the block a small amount. Don't recall the part number but it was a JE dome piston with a 0.990 pin. The trick part was the connecting rod. It was a Manley rod that was Hemi + 0.100 with Mopar big end and 0.990 small end. Super nice rod that Manley made for a few years.

Looks like it would need about a 1.43c/h with a 6.86 rod and stock stroke.
For the price of a crank, I'd just build something bigger myself.

An Icon 829(1.423c/h) would work if you can find a 6.86 rod with a .990 small end.

Maybe this is stupid...what about a 440 piston meant for a stroker? I like the RPM capability that a short stroke big bore provides, and for boost I think it would be ideal.

Molnar makes a 6.86 rod with mopar big end and chevy pin size. If my math is correct you could use a 4.375 stroker piston for a 440. +030 is .008 overbore so possibly the 0.040 or 0.055 version could be used depending on the block.

9.98(DH) - 6.86(rod) - 1.423(IC829 CH or IC843 depending on CR) - (3.375/2) = 0.0095 in the hole

Could always offset grind to 3.5" use a Chevy 6.8 and the same piston to end up 0.007 in the hole and some small CID gains.

9.98 - 6.8 - 1.423 - (3.5/2) = 0.007 in the hole

Both ways would be extra work though, but are shelf piston options.

Using the stock stroke with the 6.86 rod and shelf piston isn't any more work than doing it with stock length rods and stock c/h pistons.

True, the bore sizes on that shelf piston could run into issues though if the block needs more then +033 but other companies could make them bigger, I just haven't looked

The block is a virgin, and has no ridge at all and no pitting. But that doesn't account for taper, or out of roundness.

Thank you guys for your info. It's a lot to think about, and I was just going to build a 500 at first, but still haven't totally made up my mind.

Basically, it's either 50, 70, or 110 more cubes for the difference in cost between a new crank and what it'll cost you to have one cleaned, magged, ground.

Personally, I think the low deck 511 is a great little package.