To 340 or not.........

[Chryco Psycho]

if the machine work is done right there is no sacrifice in reliability with a stroker

 

[burntorange70]

Strokers rock! That is all. Going to want more cam if you go that way and at least a little head work if not a set of RHS or Eddys.

 

[btceng]

Burnt,

Can you recommend a stroke kit? Got it on a stand today and plan to pull the intake, heads, and pan tomorrow. It obviously got moisture in the valve covers because the rockers have some rust on them. Likewise, the pushrods, valve stems, and springs. It turns freely and sparkplugs look brand new and may have been.

 

[Chryco Psycho]

Check with Eric @ muscle motors in Lansing Michigan

 

[burntorange70]

You got a builder or are you putting it together? If you got a builder I would talk to him about it. If you then check around. Summit Jegs or Mancini racing all have good kits you can check out. Have it balanced and get a forged crank.

 

[btceng]

This will be my first Mopar engine build so I really want to do the assembly myself. I have a good machine shop nearby and a friend that is an old time Mopar man, in fact, that's his nickname.

Here's where I am now. I have torn the engine down but haven't taken the rotating assembly out of the block yet. The numbers that I find on the parts are as follows:

Block 2780930-340-8 Date 9/17/72
Heads 3418915 J
Pistons B296 040
Crank 161 couldn't see the casting

It's not what I hoped for but it is a 340. It appears to be tight and the bores are smooth with no ridge. Number 1 piston rod has rust on it but not bad. The thing has the thin balancer but the crank looks cast to me.

 

[btceng]

The lifters show no sign of wear nor the camshaft. Not sure of the grind.

 

[Chryco Psycho]

if the crank has thin parting lines & squared counter weights it will be cast but should have an offset damper on the front .
if it has wide parting lines & rounded counter weights it is a steel crank , post a pic when you get time .
the cam should have some id # & letters on the back face

 

[btceng]

Here's a few pics. Looks like a cast crank but forged dampener. Bores look fair. They have a little rust here and there that cleans easily. A quick hone may fix that. Thinking about bearings, rings, and a hone. Then build the top with new can package and have the heads done with new valves.

 

[Chryco Psycho]

I don't see the pix

 

[btceng]

Sorry about that. Long day. The second is a pic of the dampener number. Not a great picture. Where to go from here?

 

[Chryco Psycho]

the forged cranks do not have a # on them unless it is stamped into it , just part of the process to create the crank , the fact that is has a number Cast into it makes it a cast crank

 

[btceng]

Can you go .060 on a 340? I was hoping for a standard bore but it looks like I was misinformed.

 

[Chryco Psycho]

I would have the block sonic checked before I went any more then .040

 

[btceng]

I may be better off back with the 318. I know that it is a solid engine. Could stroke it and use the heads off of the 340. You are right about getting the block checked out. Thanks for the help, as usual.

 

[Chryco Psycho]

or just bolt the 340 back together , sell it off again & use the cash to buy some good heads like the RHS