440 Pistons In A 400

[Magnum-man]

Has anyone ever tryed or heard of or maybe even seen a artice about useing 440 (.020) pistons in a 400. I have a buddy who told me that a stock (low compression) 440 +.020 piston in a stock 400 block will give you a close to zero piston to deck clearance. I understand that a std.400 piston and a .020 440 piston have a different pin height.and they hence would be different thus raiseing the compression. any help on this would be great as i want to build a cheap high compression 400...to get that same results as a 383 but maybe a little more power. any indeas.....

[Stoga]

That is a darn good question! This would be like swapping 426 and 383 pistons, which both have the same bore of 4.25'.
Wish I had more info to give, but I gotta say, haven't tried this swap or seen it done. I guess the question is, what's the piston pin height of a 400 and a 440, and what the difference is and does it work in your favor? Someone else with a bit more reference, please jump in! Has anyone else done piston swapping from RB to B motors?

[jelsr]

Don't think the comp. height is a problem, the '68 383 was 1.93, '72 400 was 1.83, and the '72 and up 440's were 1.93. The extra weight (about 90gr.) could be balanced out, but the skirt length might be a problem. If you put a wrist pin half way into one of each you can see the small difference in height (.100 or so 400 vs 440) but a large difference in the skirt length, about a half inch. Don't know if it will clear the crank at the bottom of the stroke. Got my doubts.

[Jims451]

That is how they used to build the 400 stroker engines, just look at an ols issue of "Chrysler Power" Magazine. I believe the 440 piston needed to be slightly milled for the correct deck height.
One problem that occured is that the stock cast type 440 pistons could not handle long term high RPM usage and they cracked the piston pin boss.

[PRO]

Ive seen it done too but....its hardly worth it,youll need to clearance the crank counterweights so they dont hit the pistons then balancing it can be a nightmare although Ive seen it done and it ran hard.....PRO.....

[dave571]

Thier too tall to just throw in. It's my understanding that they can be milled down to get you a desirable comp ratio, more economically than buying perfomance pistons for the 400. Just have to be sure on your measurments, or you end up with a big mess.

It's also my understanding, that when this is being done, usually you go .030 over, then bore the 400 .010 so that it all fits together

[rynoracing]

I've heard of using the TRW 9:1 440 pistons in the 400 , which gets close to zero deck on a 400. There was an article on a 400 build-up in Hot Rod Magazine. I don't remember what month though. I'm going to build up a 400 in a few months and am either going to use the trw440 pistons, or the Keith Black Hypereutectic 400 pistons.

[DartGT66]

Have built one using stock 440 pistons in a 383 block bored .070" oversize. This budget "396" ran great; high 11's in an Aspen with ported stock valve heads and 292 hydraulic cam.