Is this a good deal for a 340?

-
E

ESP47

Well-Known Member
Joined
Jul 3, 2009
Messages
2,521
Reaction score
1,475
Location
Sacramento, CA
I've only owned slant 6's up until this point so I'm a total V8 newbie.

I met a guy who has a 72 340 block for sale. He said it's bored 40 over and has had all the machining done to it. Told me it was ready for a rebuild kit, some heads and it's ready to go. He also told me he can either throw in a forged crank or a cast crank that also has the matching flywheel, balancer and all that. He wants $600 for it.

Do you guys think this is a fair deal? If it is, would you guys get the forged crank or all the cast pieces? I'm just looking to build a standard 340 so I don't need huge horsepower or anything. Just an upgrade over what I have now. I figured I'd do my research and ask here first because I don't know much about these engines. I do know that standard blocks without any machine work done to them go for about $500 in my area.
 
I'd go forged just because it' the stronger of the two. The only problem I see that it is 40 over which means I'm not sure you could go any bigger. $ wise you can invest more than that in machine work.
 
Honestly if I could choose I'd get a block that hasn't been bored at all. Is there any problem with the block already being machined to 40 over? I'm not looking to go any bigger or get huge HP gains but I will admit I don't know the cons of it already being 40 over. I took a look at it for a little bit and it looked newly machined but like I told him, I could be looking at a chevy 327 and not know the difference :banghead:
 
you are going to have to get the lower end balanced no matter what crank you go with... also a good set of .040 pistons are harder to find then say a set of .030 set... i wouldnt trust someone saying "the machining is done and its ready for assy."! you still need to check and adjust ALL clearances if you want it to live a long happy life.... i would get a virgin block and start fresh. at least a block with a crank in it. JMTC...
 
I'd at least go look and get the number off it. Never know, might reunite it with the original car.
 
68GTconvert said:
I have a standard bore 340 Block with mains only down in Marin. PM me if interested.
Click to expand...

This is a shot in the dark but what is the VIN? My 71 Duster is missing it's 340. Story goes that it spent some time in the SF Bay area before SoCal. It is originally a New Mexico car.
 
Price seems fair to good if the block and machine work is good. Like was said .040 over is about maxed out on the bore. That meaning this will probably be the last rebuild on that block.
 
.040 over is the max you can go on a 340. Also means that it will be the last rebuild on that block unless you resleeve the cylinders Big $$$. I picked up a std bore 340 for $800 and then spent $2500 on the machine work. It needed to be bored .020 over but I know that I have at least 1 more rebuild out of that block if I need to. $600 is a good deal if the machine work has been done and done right. I would check on who did the work and then go from there.
 
Thanks guys, looks like its kind of a mixed bag of opinions. I have a coworker that used to work in a machine shop years ago, so I'll see if he'll run down there and check it out with me. He's not a Mopar guy but at least he'll be able to check things over that I wouldn't notice.
 
Price the whole swap too. If your car is 1967+, you will need a V-8 K-frame or brackets. Also, V-8 steering link, different transmission, usually a bigger rear-end and thus shorter driveshaft, maybe disk brakes. Probably new throttle cable, radiator, ...
 
Bill, the car is a 67 but luckily it has a 273. The bad news is it's small bolt pattern with a 7 1/4 rear. Just got a 73+ disc brake setup in the mail today and I'll wait patiently for a bigger rear end to come around.
 
Whenever I here this is done or thats been rebuilt, I disregard all of it. Unless I have positive proof otherwise.

I just built a friends (rebuilt 340) he bought at a swap meet.
The cylinders were 2-3 though different from side to side, the timing gear was not on the key all of the way, the pistons were 12 to 1, and the cam was huge, also they had too long of main cap bolts in the 4 for the windage tray, they were bottomed out and not even torquing the caps!

So, be very wary of so called "work done". A lot of people don't know what they are doing.
 
You must log in or register to reply here.
-

Back
Top