Author Topic: 340 heads  (Read 886 times)

Offline black71

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340 heads
« on: June 17, 2007 - 04:53:51 PM »
i have a 73 340 and the heads say 360 on them...what heads do i have? and what are the best production heads for a 340?




Offline 360 'CUDA

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Re: 340 heads
« Reply #1 on: June 17, 2007 - 05:18:07 PM »
you have 1973 340/360 heads.  The best production 340 heads are the 68 to 70 J or X head with the 202 valves but yours would work just fine with some mods. 

Alaskan_TA

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Re: 340 heads
« Reply #2 on: June 17, 2007 - 05:41:37 PM »
Lots of 340 heads say 360 if they were made after 1970.

U, O, J and Z heads are all the same, all good. The letters actually mean nothing, you have to go by the actual casting number and how they were machined to know what you have.

X heads are a little different but still good.

Look for the large valve sizes.


Offline black71

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Re: 340 heads
« Reply #3 on: June 17, 2007 - 08:06:47 PM »
right on thanks for the info!  :dunno: i cant make up my mind on what to do, build my 340 or 440. i wanna be able to drive the car fairly often....generally i would say 440 but with the price of fuel and going to college i just dunno...what would you guys do?

Offline 360 'CUDA

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Re: 340 heads
« Reply #4 on: June 17, 2007 - 10:08:12 PM »
Next time I'm gonna do the Edelbrocks  ;)

Offline cudabob496

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Re: 340 heads
« Reply #5 on: June 17, 2007 - 10:20:09 PM »
I wouldn't think the milage would be much different between a 340 and a 440. If there is a possibility of being at a red light with a camaro next to you, what would you rather have under the hood? :)
72 Cuda, owned 25 years. 496, with ported Stage VI heads, .625 in solid roller, 254/258 at .050, 3500 stall, 3.91 rear. 850 Holley DP, Reverse manual valve body.

1999 Trans Am, LS1, heads, cam, headers, stall, etc! Love to surprise the rice rockets with this one. They seem so confident, then it's "what the heck just happened?"

2011 Kawasaki Z1000

Offline black71

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Re: 340 heads
« Reply #6 on: June 17, 2007 - 11:22:46 PM »
haha true true and there is nothing like a mopar big block with a nice lopey cam!!!

Offline Chryco Psycho

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Re: 340 heads
« Reply #7 on: June 18, 2007 - 12:03:32 AM »
the best head for power I have found is the 88-92 #308 Truck casting , they will embaress a set of 340 heads X,J,etc

Challenger - You`ll wish You Hadn`t

Offline Carlwalski

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Re: 340 heads
« Reply #8 on: June 18, 2007 - 01:05:31 AM »


I got some NOS 308 heads off eBay about 5 months ago. :bananasmi
Not sure why I'm telling you this. :lol: Dad owns them now but they'll be going on his engine.  :thumbsup:
1970 Dodge Challenger R/T
White, License Plate, 0A-5599
540ci Aluminium Hemi, F.A.S.T EFI
TF-727 Gear Vendor OD, Dana 60