Piston/Performance Build Up Help!

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wjaholic

wjaholic

My car stole my wallet!
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I am rebuilding a 440 from a 73 Chrysler Imperial, I am doing it on a very tight budget. I have gotten to the point where I am ready to put the pistons and rods back in, I was orginally going to reuse the stock pistons but now I am having second thoughts. I have had the block rehoned and checked for straightness, I picked up a set of Childs& Albert File fit Dura Moly rings. I would love to have higher compression but my budget isn't going in that favor. Most everyone I talk to is telling me to change the pistons so I have started questing for higher compression pistons. I am going to run the stock 346 heads (ported and polished - slightly, 3 angle valve job) stock cast crank (3.75 stroke) stock rods (6.768 length). I am running comp cams 21-223-4 (3 bolt version) (set to 4 degrees advanced), Weind Dual Plain Intake,Pro Gear Double Roller timing chain set, Felpro Valley pan(heat risers blocked off), Clevite 77 bearings (Main and Rod) and 750 cfm Carb. I would love to have the compession ratio in the high 9's :tongue1: but.... I am trying to do this on a budget, the rest of my 74 Duster still needs work. Cant blow all my money on the engine/transmission. Can anyone help me out? I have posted in several different places that I am looking for new or like new higher compresssion pistons. If I don't have any luck in 60 days (when my posting expires) I am going to look at Monster Mopar(swap meet and Manufactuers midway) and go from there.

Also what do you think of my combo, 74 Duster - Auto 727 - (Probably) 2200 Stall - 8-3/4 - 3.23 Posi, all rebuilt suspension, beefed up front end. If any one would like to see pictures just let me know.
 
wjaholic said:
I am rebuilding a 440 from a 73 Chrysler Imperial, I am doing it on a very tight budget. I have gotten to the point where I am ready to put the pistons and rods back in, I was orginally going to reuse the stock pistons but now I am having second thoughts. I have had the block rehoned and checked for straightness, I picked up a set of Childs& Albert File fit Dura Moly rings. I would love to have higher compression but my budget isn't going in that favor. Most everyone I talk to is telling me to change the pistons so I have started questing for higher compression pistons. I am going to run the stock 346 heads (ported and polished - slightly, 3 angle valve job) stock cast crank (3.75 stroke) stock rods (6.768 length). I am running comp cams 21-223-4 (3 bolt version) (set to 4 degrees advanced), Weind Dual Plain Intake,Pro Gear Double Roller timing chain set, Felpro Valley pan(heat risers blocked off), Clevite 77 bearings (Main and Rod) and 750 cfm Carb. I would love to have the compession ratio in the high 9's :tongue1: but.... I am trying to do this on a budget, the rest of my 74 Duster still needs work. Cant blow all my money on the engine/transmission. Can anyone help me out? I have posted in several different places that I am looking for new or like new higher compresssion pistons. If I don't have any luck in 60 days (when my posting expires) I am going to look at Monster Mopar(swap meet and Manufactuers midway) and go from there.

Also what do you think of my combo, 74 Duster - Auto 727 - (Probably) 2200 Stall - 8-3/4 - 3.23 Posi, all rebuilt suspension, beefed up front end. If any one would like to see pictures just let me know.
Click to expand...

when you can afford it, I would recommend 3000 stall converter, and 3.91 gears. That 440's going have good torque in the midrange and this is a good way to utilize it :evil2:
 
LOL ha ha ha h, pictures are allways good!

Have you thought about head milling? I don't know how much it would take, but it's a thought.
440's do well even when the compression is down some.
 
If the budget doesnt allow for much, I'd avoid it. You dont need 9:1, you just want it. That cam will run just fine in the stock 7.5ish:1 longblock. I dont know of any 3 bolt version of it, but if you have it in your hand, it must exist. Once you get into changing pistons, you also change the balance of the lower end. The factory balance is poor at best, and I wouldnt install the earlier pistons on it just for that. Run steel head gaskets with them, and I wouldnt mill or do anything else, just put it back together and run it.
 
Just remember, both block and heads need a special (very smooth) finish to run Cometics. Make sure you tell the shop you want to use them. The MP ones are about 20% of the cost of Cometic MLS ones too.
 
Don't forget that the 346 heads are not for unleaded gas. It wasn't til the 452's that came with hardened seats....
 
I recently had my 400 rebuilt, also on a tight budget. I had my 452 milled .060". Just make sure for every .010" milled off clyinder head face that .0123" is milled of intake side of the head.... I had to take mine to a couple of different shops before i found one that could do this for me. that should put your compression around 9.5:1. I also used MP steel shim head gaskets, engine runs much stronger and has more grunt down low.
 
Thanks for everyones input but I have decided to open up another can of worms. I was on a mission at monster Mopar this last weekend and actually found a few different things for my car. :toothy7:

Among other things I picked up a set of closed chamber heads. 516's actually, I am planning on taking them to a machine shop and having the exhuast seats cut out and changed to the larger valves from my 346's. I am also going to see what it would take to milled down a little bit. What do you guys think of this setup?
 
Keep your 346s...........offset grind the crank .060..........u will gain slightly more than 1 compression point + 13 more cubes, a cheap way to more compression and extra cubes. U should rebalance the recip assambly.
 
I lie the 516 idea. My own factory '70 vintage 440 has 516s milled .100". With steel shim gaskets it's at just over 12:1. However, milling begets more milling and parts. Run the 1.74 exh valve, and have a blast.
 
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