Is a 340 crank and 318 interchangeable?

[Cranky]

I thought only 318 truck engines came with forged Cranks?

Nope. I also pulled a forge crank out of a 67 318 about 10 years ago. It was an original motor to the car....

 

[Cranky]

Bumping this somewhat elderly thread back up with a question: An associate has a 318-3 crank that I can buy....anyone want to opine a ballpark on what the current value of a "std. x std." one might be? I don't really have any particular 'project' for it to go into, but it's one of those - "yeah....I should probably buy this if I can" situations.

Thanks in advance.

Mark

Did you buy that crank? With today's prices I would think a couple hundred dollars or more even....

 

[RemCharger]

To quickly wrap up my initial post, the guy ended up finding a 340 crank I believe.
But the reason I asked is because I have what I believe is one of those 318-3 cranks in a motor. Have to get it and pull it apart. Lots of good info here.
I also have a 67 318 car motor coming in. Maybe I should grab that crank too.

 

[MarkLevi]

Did you buy that crank?

Yes I did. I haven't picked it up yet and put a mic on it - in the next week or so. It is part of a rather large parts package I bought from the guy. I thumbnailed its "retail" value at about $250 based on apparent "rarity" and being std/std. I may resell it, or maybe put it in "something"...I really don't know as-of yet.

Mark

 

[Cranky]

Yes I did. I haven't picked it up yet and put a mic on it - in the next week or so. It is part of a rather large parts package I bought from the guy. I thumbnailed its "retail" value at about $250 based on apparent "rarity" and being std/std. I may resell it, or maybe put it in "something"...I really don't know as-of yet.

Mark

It is balanced differently since the teen has a lighter recip assembly......not sure how hard it is to balance it for a 340 setup. I generally balance a new assembly anyways. The factory balance is ok for grocery getters but not that good for the high rpm builds.

 

[MarkLevi]

...balance it for a 340...

My immediate thought on this would be aluminum rods to try to get away from having to add counterweight - but I've never had my hands on one of these before, so I don't actually know jack! I have a very good scale and always static balance my pistons/rods assy's, but I have to send anything out for dynamic. I have a couple 340 blocks/rods/pistons/1.88 heads....if I could ever find a "door-jambs-back half" for my '70 barracuda, that would probably make a nice mix.

 

[MarkLevi]

@GTX JOHN : It's fine that you disagree....but with "what"? Did I value it wrong? - if so, is it "scrap rate"? ...nothing?, or $500? ... or more? Is it something else you disagree with? I value other's opinions on things like this - would appreciate more than a "drive by".

Thanks
Mark

 

[GTX JOHN]

I have a several 1967 Model Year 318 engines in the shop that have never
been rebuilt. They are casting dates of late 66 to mid 67. They all have cast
cranks and I am pretty sure they are original. I do not doubt that some may have
had forged but not all did that year.
If the 318 forged cranks are standard, I have been selling them for $150.00
If they are cast I have been selling them for $50.00
The 340 standards I have sold this year for as much as $250.
if cast $50.00

The cast cranks are lighter and some Stock and Superstock racer prefer them
for that reason. However,I do not.
Unfortunately, the cranks are a fortune to ship (often $100.00) and usually need to
be straighten after shipping due to rough handling.

I think I hit the wrong post with the Dislike button = Sorry a lot of distractions at
the race track.

 

[MarkLevi]

If the 318 forged cranks are standard, I have been selling them for $150.00

All good - my "thumbnailed value" may have been optimistic I'm still above water if I sell it in the range you do. Who know what I'll actually ever wind up doing with it - not me! LOL. Couldn't pass it up, tho...addict
Thanks
Mark