915 J heads, need specific machining details to squeeze as much as possible out of them

-
moparodbuster

moparodbuster

moparodbuster
Joined
Jul 12, 2006
Messages
74
Reaction score
4
Location
Melbourne, Australia
From what I gather, the 915 J heads aren't going to flow much different than the eddys if machined properly so I've gone ahead and bought a pair for $300. They are untouched from factory out of a 71 360. Im in Australia and there aren't any machine shops that are familiar with what I need to do to them now to get them to their 90% potential so I need specifics to tell my machinist exactly what to do to them. Hoping for experienced advice. Thanks for the help!
 
I'm betting we can drag this post out to 3 or 4 pages before he goes with aluminum heads & junks those cast iron things.
 
72Dart6pack said:
I'm betting we can drag this post out to 3 or 4 pages before he goes with aluminum heads & junks those cast iron things.
Click to expand...
Probably.
But I'm weighing the same decisions except my J-heads are already on the motor. I tend to like to use what I have. I might even take a swipe at carving on them before I go the next step. I'm not going to dump a bunch of money into them just to prove that it can be done though.
 
All you need is a guy that knows how to port heads. You have some decent guys over there - go find one. The wrong guy will trash the heads. Or leave you paying a bill with little return on investment. So find one. That would be my advice.
 
Good 70* throat cut, 5 angle cutter over that, shorten guide tail an profile, grind out the roof kinks and if you go through a lil into the lower head bolt pad... just JB a hardened washer over it when you install the heads and bolt them on. I'm racing tomorrow in barona, but if I dont too pissed drunk afterward... I'll post some pics of what it should look like.
 
You must log in or register to reply here.
-

Back
Top