Who here has done a 400 block , 512ci combo? Planning on my future engine for my 69, and want to start gathering parts. Does anyone make a "shelf" piston for this combo? What length rod is used?

Here is my thought:

400 block with half fill
BRC aluminum main caps
Molnar 4.250 crank
Molnar rods
Pistons?
INDY SR heads w/MW ports
INDY 4150 intake
Holley 1000cfm carb
Comp Pro Magnum rockers
Roller cam to be determined later
11:1 compression so it can run on pump gas
Hooker 2" Super Comps

FWIW,
I built my own combo with a 4.25, 6.7 rod, and 1.12ch mahle piston.
Better rod ratio and lighter piston. These are the shelf piston for the 4.15 kits.
The kits are usually 4.25,6.535,1.32.
My mahle pistons were only 452 grams each. They should just make the kits like this in my opinion. I did have to take .010 more off the deck but that’s barely worth mentioning.

What length Molnar rods did you buy? The rod length will determine which type, shelf or custom, piston you can get for your motor
I like long rods, I've used 6.800, 6.700 and now in my current 400 block 512 C.I a set of 6.535 long Crower billet steel BB Chevy type rods that I bought used along with the Windberge crankshaft for this motor, I hope they are not hurt where I can't test for cracks
This motor is a 3/4 serious pump gas motor 440-1 heads, Crower older SS grind solid roller cam and so on
My original 400 pump gas stroker motor made 727 HP with a 4.300 long stroke crankshaft with a set of Indy SR M.W. non CNC ported intake ports and a small solid roller Comp Cams, 260@.050 intake side with .420 lobe lift and 266@.050 on the exhaust lobes with .409 lobe lift ground on 108 LSA installed at 106 to 107 ILC That motor flat exceeded all of my expectations over and over, it had four sleeves in it also

That's pretty much what I run....Its a 400/512 pump gas combo, but from 440 Source. I went with the light weight option on mine.

Its pump gas for cost reasons, and has gone 9.70's....Looking to go quicker though. I really thought I would hit 9.60's this year with this combo, but it didn't happen yet.

So I might send the EZ1 heads out for porting, and look for better rocker gear...It runs pretty hard, but its still a little slow on the top end. I might have found part of the issue is a header tube weld let go bad.....Fender well headers are loud, and I didn't even notice.

And you will need a 1050 or better...It likes fuel. The engine is out for a freshen up and is actually sitting on my tool box right now.

http://www.440source.com/strokerkits.htm

mine is the 4.250-6.535-1.32, molnar rod and crank Icon shelf piston combo,, w/ TF 240 heads been 9.80's with it

I went with the 440 source set up, 4.25,6.535 & 1.32 piston, mine is a street strip car, love it !!!

Lots of people make shelf pistons for a 4.250 stroke in a 400 block. Typically people use a 6.535 rod but you'll just have to flip thru a few catalogs. There might be shelf pistons for a 6.600 or 6.700 long rod also. You need to know the combustion chamber size before you can pick the piston if you're shooting for a specific compression ratio. You'll need a dished piston for pump gas.

Thanks Andy. This is for a long term project/Drag Week type car. It needs to have tall enough piston to last plenty of street miles.

Diamond makes a shelf piston 4.375" bore w/ .990 pin, 1.32 CH, -12.5 rev. dome that works really good w/ a .041 MLS head gasket and say 82ish cc heads. Much smaller than that and you will be at -24cc dish. I was not able to find any metric ring packs for 4.375 bore. Definitely no metric hellfires in that bore size speaking from 2016.

JE dug up an 0.043 top ring for me on my last 470 build but I think that is about it. No metric ring packs that I know of for 4.375 and the 0.043 ring seemed to be odd enough that JE had to special order it. That was a year ago so there could be something new on the shelf now. Last time I looked all of the shelf pistons used an old school 1/16 ring pack. Change comes slow for the Mopar world. That Ford FE I worked on last year got a metric ring pack on a shelf piston. So the vendors make them for a dinosaur like an FE but not for a Mopar.

I've had a 400/512 in my '65 Coronet for 15 years. Of course, it doesn't have many mile on it but the concept has been around for a long time. I used a 4.250 Callies crank with 6.535 Crower rods and a JE piston. No reason an engine like that couldn't last for 50K miles if you keep the oil clean. EFI pays for itself in increased mileage and reduced ring wear if you're going to drive it a lot.

Good choice in rods & crank in your planning. I have the same in my 512 combo. I was thinking of 440 Source rods but found their set was 1000grms more weight & then at the time a friend had his Source kit break a rod & destroyed his engine, he also went Molnar on the rebuild. My street car has a similar spec to your build idea except it has Stage 6 heads, but i would have gone Indy if the Stage 6 werent already kicking around. I went with the girdle on my build, its been holding together for a few years now & i have it running mid 10s with a 950 QF carb..

I forgot to mention I do not like or recommend using block filler on any build The main reason is you end up with two different heat zones in the cylinder walls and that is not good in my opinion

Doing 400/512 now. Blocks at Hensley's Performance in Knoxville TN. It's Molnar crank and rods 4.25 6.535 & 1.32 Ross pistons. Pro Gram 2 bolt caps bushed lifters bores. Will be running TF 240 heads B3 rocker correction Holley StreetDom Compression 10-10.5. Talked to Dwayne about a cam. He kinda came up with a modified 528 style solid with EDM lifters. That was just in conversation we had. But will nail the specs with him in a couple weeks. This is street car with OD and A/C. Like to be able to cruise it all day. And if I wanted to make a pass with it. Roll it out of the lights. If it runs a high 11 low 12. I will be totally thrilled.

Used Icon pistons in mine.