74Runneer

So i found out my cast iron heads are cracked, do i look for another pair of 302 cast iron and spend the time and money for a valve job and port work, or do i just slap on a pair of aluminum edelbrock RPM's? What are the pros and cons of each? Also what work would be needed to put the rpms on? does it need any machining?

I have a 318 with a 600 cfm eddy, hedman headers, eddy performer intake, and i believe a 340 like cam. (how do i measure the duration and lift?)

I dont know what i would do without you guys!

Gorts 5th

A 318 with edy heads the valves are larger than the motor needs and you will have to have the cylinders chamfered. you will be loosing low end performance.
A set of 360 heads milled 0.30 with the stock 1.88 1.60 valves will net you better results for the cost.
Porting them will be even better.
The cam sounds like a 268 duration 450 something lift.
that's what i would do on a 318

rcknrolfender79

http://www.moparmusclemagazine.com/t...d/viewall.html

Here is a good build that may help you out.

74Runneer

So milling 360 heads .30 will get the compression up to its not a dog at low end? Also if i went with the 360 then i wouldn't have to buy new valves and do all that work. What year 360 heads are the best for this? Would it even need port work? 360 heads have to flow a ton better then stock 318 heads right? What would the compression ratio be with stock pistons?

Gorts 5th

i have found that the VE of the heads are perfect for a 318
i run a set of ported 360 heads with stock valves and she has very impressive torque
your kinda trading Velocity for volumetric efficiency, i'm learning... i think it works because of the long rods in mopar motors the geometry is fascinating as spock would say.
i have been running this type combo for years hell decades.
use the stock 1.88 1.60 valves they are perfect for you motor
i am running ported 360 heads 587's, with the stock vales but i ported them to the max.
from what i,m learning the long rod la's work with this set up i think it has to do with the time it hangs at the top and bottom of it';s stroke something furd and chetty lack.
and with a lunati cam!...my next.

74Runneer

Okay i think ill go with the 360 heads. What years am i looking for? is there smog era heads that i should avoid?

Gorts 5th

nice article, it's definitly possible.
my cam is 275-284 462 482 lift and duration none magnum 360 heads ported with 1.60 1.88 and she's a screamer, she sounds like a 340!
my brother says she has to have over 350 hp!
i say i need to get it too the strip!

74Runneer

Okay i need help finding some 360 heads. Are J heads only made from 71 to 72? Are 1973 360 heads any good? how about any heads from the 80s? I have them to have the hardened valve seats. What should i look for and how much should i pay?

TVLynn

CC the heads and cut them down to 62-64 CC .030-.040 You need to cut the intake side also. Shouldn't have to pay more than $100 for the pair. Now if you want the X or J heads They will cost a lot more. Any year 360 head will be fine on your 318. The smog holes in the ex port can be plugged with some brass/ aluminum rod- just hammer a short piece into the port and cut it off flush Or leave it open the manifold will cover them and they will eventually carbon up

74Runneer

Okay i dont think i want to fess up the money for the J or X heads. Why are they so much more money? What years dont have the smog ports? or which do?

Chryco Psycho

The X&J heads are not worth the $$ anyway , I have made a 41 RWHP gain just swapping X for 308 swirl castings with port work on both