Picked up a 70 440 that guy had sitting around for 6 years and of course taking it apart see what is in it. It had machine work done told less than 25k on motor when the other guy bought it. It is 30 over everything looks super clean virtually no wear. I am no engine guru but like to do it myself and learn as i go. what I know, forged crank, std LY rods attached to Silvolite 1276 pistons, mild MP cam (have not measured it out yet), 452 heads. Looking up the pistons they are lower on the comp range. I am looking to replace my original 383 in my 70rt chally with this 440 and like to have mild build.
Couple questions:
Pistons - I suspect changing out the 1276 for something give me lil higher comp be a good thing! maybe 9.5:1 range? or keep em go turbo (not) n/a for me.
452 heads - worth going aluminum route, i know weight be a savings, but actual cost vs hp??
if I change pitons and heads htne matching cam too?

Ideally like to change out the pistons.
Btw - going ot run 750 eddy on top alum single plane street master for now $$$.. till i can probably step up to 800cfm & RPM.
I am going to call 440 source but wanted to get some feedback/ideas first.
thx

 

Sounds like a fun project. If you are thinking of running a turbo, or nitrous or any other type of forced induction, I would steer away from the Kieth Black Silovlites. They do very good in mild builds but they are still not near as durable as a good forged piston.

I would recommend over building the bottom end for upgradability later. A solid bottom end with good set of forged pistons will cost you a little more now but if at a later date you can add higher performance heads, cam, supercharger, turbocharger, nitrous or what ever. If you never upgrade power output you still have a solid bottom end that will last you a long time.

I also have a 440 that is .030 over sitting in my garage. If you do decide to change the pistons, and you can seperate them from your rods with out damaging them, I would be interested in purchasing them. I would like to see how cheep I could put together a mild 440 for.

 

Yeah I let you know if/when I pull em. My friend thinks I should bolt it up drop it in and go dyno it. Then decide what to do based on where I am at. Interesting idea, but more work. I am taking the intake and carb off the 383 to use so I have only gaskets costs involved at this point to re-assmeble. I am going to get more info on pistons first then decide.

 

First thing I must mention is stay away from Keith Black, I have heard nothing but bad things about them coming apart or cracking.

Next look at the compression ratio and decide what fuel you plan on running. The ratio now sounds perfect for pump gas. But again you have to look at the heads you plan on using and the chamber size especially if you are looking to change pistons.

I have a built 440 very similar, but on the higher cost end, take a look at my thread.

 

The 383 manifold will not fit on the 440. The 440 is a raised block and the 383 is a low block. The intake, push rods, valley pan, and distributor will not swap from the 383 to the 440.

 

That is correct sir...the 440 is wider...oil pan and other stuff will.

 

The is nothing wrong with Kieth Black pistons for a street machine. I run thier pistons. I run the KB237 in my 440. The problem occurs when the rings aren't gapped according to their requirements. The pistons expand and you will break the the ring landing if you don't file the gap right.

http://www.kb-silvolite.com/kb_car/p...etails&P_id=30

 

Yeah...true 383 manifold is a not go. Now I can tell my wife need the new performer after all!
So on Pistons, looking at some speed pro give me about 9:5 to 1.

Another question for you guru's - If I change to a forged piston will weight diff from my cast alum require me to do some rebalancing? Or should I stick to similar material to keep weight close.

or just spend money on intake and 800 cfm carb and keep the 8 to 1 piston i have for now!

 

Any true high performance motor should be balanced as an assembly with your new pistons. Can you run the forged pistons with out a rebalance? Yes you can. People do it all the time but it is not recommended in a performance rebuild. Of course you do not know if the previous rotating assembly was balanced either.

 

Im rebuilding a top end on a 1977 440. Using 906 heads, RPM Performer Intake, Carter/Edelbrock 750. Wondering how this will work with the dished pistons. 440 Magnum cam. It has good compression and no smoke with the old 452 heads.

 

Consult your machine shop too.. Forged pistons require different clearances !!. Weight should be close but it is always best to balance !!!!!

 

The 906 heads are good heads but in your application I would look for a different set. They are an open chamber design and will not really net you any gain in horsepower. If you can find either a 915 or 516, they are closed chamber design and will bump up your compression a few points. The only draw back is most of them have smaller exhaust valves 1.60 size. The 906 and most newer model heads have 1.74 exhaust valves. The one exception is the 1967 440 hp 915 head. It is closed chamber and came with 1.74 exhaust valves. It is easy for any competent machine shop to put the larger valve seats and valves in the smaller valve heads. Being as the one of the main killers of power on your 440 is the low compression ratio, adding some compression should help wake the engine up. If you must use the 906 heads, then try and use the thinnest head gaskets you can. Compression is the first place you should look on this engine to make power.

 

Ok thanks for the info. The 906 heads with the RPM performer and 750 Edelbrock work real well. Just drove it today 4 the first time. I realize compression is the limiting factor at this time. So need to go to a dome piston next, but that will be awhile. Other parts of the car need attention. Like how do I get the speedo and instrument cluster out? Anybody?