341 hemi in 1970 dart

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Kbharley

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What are your thoughts on putting a 341 hemi in a 1970 dart swinger???
 

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Yup. Total coolness. See my avatar. Hangin on the stand in my shop. You'll be needin Bob Walker's help.

http://hothemiheads.com/

Nice little 371. Those are hard to come by.
 
Might want to look up Zigs , he has an early HEMI in a 68.....
 
They were famous for soft crank shafts and poor oiling. I have had three variations.....331 , 345 and a Dodge 241 Red Ram.
Then they weigh a ton. ( not a lot of exaggeration there. )
But they look AWESOME !
To put one in a street rod and pussy around town in would be the cat's ***.
But to make one fast takes dedication and dollars.
No room for half measures.
 
we...........just...........had............a...........thread............on...........this
 
Soft cranks? They all had forged cranks in them!!! Frist rumor I heard of this!!! Do tell!
 
Be sure to use big block (or thicker) torsion bars, unless you like the way a Chris Craft handles.
 
I have no clue where the soft crank thing came from, but that's totally inaccurate. In fact, Don Garlits himself has said and proven many times that the cranks in stone stock form will withstand in excess of 1200 HP. The cranks are the strongest part of the early Hemi.

Read this. Scroll down to the crank section. http://www.hotrod.com/techarticles/hrdp_1206_the_early_hemi_guide_of_death/viewall.html

I don't know where you came up with that info, but it's wrong.
 
If you weren't so far away, I have a 392 and/or a 331 I would sell you.

I put a 392 hemi into my '68 Barracuda when I was 16. It worked well except for the left rear exhaust was very compromised by the location of the steering shaft. A smaller hemi like a 354 or Dodge 315 hemi would fit a lot better. I pulled the motor out 20 years later and put it into a '56 Plymouth instead.

I will be putting a 331 hemi stroked to 378 in my '70 Satellite with aluminum heads to lighten it up. The last picture is the current state of my 392.
 

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My 331 is up for sale in the for sale section now.
 
I'm pretty sure Big was referring to 392 cranks , which they used stock , welded and offset ground etc. etc. and had a lot of success with.
The soft crank / forged connection means what ?
Forging definitely provides a denser core , but it is the surface hardness that I am referring to.
The issue was caused by ( here is my best wild assed guess ) insufficient oiling , bearing materials that were 1952 quality , leading to material embedding in the crankshafts , resulting in trenches where there once was a well machined bearing surface.....because once they started to turn , they dug in and .......I am not shitting..........050" deep trenches on the rod journals.
If it was just one , I'd go " hmmmmmm" , if I had built them all , I'd go " aw , **** ". But it was on three of them.
And ( this was in the early 80's ) some of the old timers told me to expect a lot of this. I can't pin down a year , but the 354's ( 1956 ) seemed to be
when it became less of an issue.
Comparing a 331 to a 392 is like comparing peanuts to squirrel ****. There is a definite link , but it is not that solid.
 
we...........just...........had............a...........thread............on...........this

The 2010 thread ? Dog years ?
Sorry.....I missed it.
Rusty Rat , you can stand by what ever you care to believe.
Trust me.....the 1,200 h.p. cranks they refer to are 392 pieces.
 
... is like comparing peanuts to squirrel ****...

Really glad I wasn't drinking anything when I read that....

As far as soft journal surfaces, can't those be hardened?
 
Yeah.......later they nitrided some of them that went in Chryslers if memory serves me. By the late 50's the writing was on the wall from a passenger car and production stand point.
Guys had journals hard chromed ( Chrom-a-shaft was one outfit that would do this )
The bad rap with nitriding has always been un-equal depth of treatment....it is essentially a case hardening and the number they shot for was .010 thickness...and often got .005 on one side and .015 on the other.
It still strengthened the parts , but until more advances in heat treat technology came along , it was as much a crap shoot as an improvement.
 
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