I should be getting a call from Todd at Marsh Performance any day to confirm shipment of a new aluminum block. I would like input on what to do to make this shortblock meet or hopefully exceed the 926 hp the megablock made.
I will be reusing the 4.315 stroke crank, heads, valvetrain and induction.
The megablock had 15/1 compression, line2line skirt coatings, .043 top and second rings, low ten oil rings. Gas ported, 6.86 hbeam 2.20 journal rods. Sugestions?

Well since you asked
1) Belt drive if you do not have one.
2) 55mm or larger cam. does not have to be roller bearing.
3) Belt driven oil pump. Does not have to be a dry sump but that would help to.
4) Fuel Injection
5) That is a big number already for 440 -1 so you are going to have to get after it pretty hard. Not sure what manifold you are using but look into the 3X from Indy if you have not already.

Still waiting on the call, keep you posted
Todd

Based on another recent post I’d say........ put a pro charger on it

Already have a 3x, gear drive. The cam is an inverted flank roller from mike Jones. Budget says bigger cam might not be in budget.( + pushrods, springs, lifters to match?) Don't know how i would find room for the belt on a belt drive oil pump. Hoping to find a little power in a great ring pack and type, need your input on that and pistons. I may go to 7.1 long rods but if using the original 6.86 hbeams i have won't make for less power or too heavy of a piston i will stick with them. They have dyno time and 7 runs on them.
Dwayne what are your thoughts on pistons rings and rod length?
Procharger aye? Would be nice but $$$$$$$$$$$. New trans, driveshaft, axles, cage upgrade and chassis cert, license upgrade, 😒

I was in the same boat as you. Wanted to make a certain level of power to run a specific class. It would have been a real stretch and max effort with my heads.

I talked to Todd and we decided different heads would go a long way to achieving my goals. It did add significantly to my budget but I still believe it was a good choice.

Todd has been great to deal with from ordering my KB wedge and engine build.

How much crankcase vacuum do you run? Can you run more vacuum? If so, talk to some ring mfgs and see what they suggest for a high vacuum ring package. You will spend a lot of money chasing small gains. If you want to spend a lot of money for big gains then sell your -1 heads and buy some 572-13 heads.

Andy good advice and the same that Todd gave. That is the direction I went.

I have no idea....You are 200hp ahead of me on one of these.....lol, so I will be keeping an eye on you to see what I can learn. My little 541 is starting to come together and will have 14.5:1....So we will see where I end up...

Sell me the bad megablock. I PM'ed you

Thinner rings and spacers

I used to run 10 inches of vacuum, but want to stay out of trouble so not sure how much to run?
I would love to switch heads, but budget is tight so i am looking for what ever i can pick up for power at a little lower cost. Basically what pistons and ring package, vacuum, stuff i may have to buy anyway. Todd suggested a belt drive rather than my gear drive, may go that route.

A belt drive frees up a little power and makes the engine easier to work on but it is expensive. A belt drive distributor also frees up a little power and works a little better but again, fairly spendy. No doubt you can find some power in rings, vacuum, oil weight, belt drive, etc. but those are all fairly small increments. Changing the heads would add 100 hp.

As has been said already, heads would get you the most power, but would be $$.
Bang for the buck? I would go with a 4.5" crank and 7.1" rod. More power especially at shift recovery, lighter bobweight, and not much $ when you sell your old stuff.
Plus would be a better foundation when you finally upgrade your heads.

I agree that would be great to get a rew more cubes.
My current crank is a Crower center wieghted piece , replacement cost over $2500, best steel short of billet (en30b?) Rods are 849 gram hbeam 2.200 journals, so not a lot to gain? Since i am going aluminum block that center wieghted crank may aid in less cylinder distortion and better ring seal.

I didn’t see it mentioned, and i would have to search back to your eng build threads from past, but oil pan design. A good scraper , maybe zero clearance teflon scraper. Good oil pan.

I have a Charlies pan that is very good. Uses a big screen. I tried a scraper but showed no gain at the track, and gave up trying to stop it from leaking. I would assume the next move would be to a dry sump but i would have a real problem packaging that with my current setup.

Didn't realize you had a high-end crank, I wouldn't replace it with standard 4.5" stroker.
Now I'm thinking 4.625" center counter weight rotating assembly, hard to find and expensive, but still cheaper than heads.
you are at the point (as I'm sure your realizing) that any gain in ET is going to be expensive. I don't think better piston and rings are going to get you there. Start thinking about future upgrades, more cubes make more power under the curve, easier on the valve train, less sensitive on matching the convertor, etc.

Already gave you a piston, pin,ring pkg. (Yes, you'll gain hp and durability).

Go with 7.100" long Molnar rod # DH7100VTB8, the longer length will get the piston lighter, and won't load the cylinder liners as hard as the shorter rod (better ring seal, better durability).

A belt driven cam and distributor isn't going to show you big gains, spend the money where it matters more.

I did a 470 that was 10.5-1 compression, single 4150 carb, 400 cfm head, 277/285/112 in @ 108 that went 8.50's at 2920 lbs., you should run better than that.

Some decisions have been made so far. I want to go with Gibtech for pistons, file fit ss .9 mm, .9mm, 3mm rings , lateral gas ports because the primer plus produces a lot of carbon, a belt drive. The gear drive i am using is most likely a big contributer to past valvetrain issues and though it puts a huge hole in the budget, important. Rods will be 7.10 molner. I want to go with line2line skirt coating again since the megablock produced very good numbers with it, far exceeding my expectations despite one weak cylinder and the geardrive, which i understand takes a lot of power to run. Now all i need to do is fund this deal. 🤔

I am jealous....
I should have driven over to Todd's and taken your block home with me.....
I have a good set of B1 originals that would go with it. LOL

But I plan to run next year with my same 570 hp iron headed, truck motor...

I would stay with the crank you already have, with 4.500" bore it will be great.