69MOPE
Well-Known Member
Has anyone ground thru into the coolant passage during porting J heads and where are the areas that are closest to the coolant passage?
Porting J heads ?
- Thread starter 69MOPE
- Start date
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I ported a set, got too thin in the intake and exhaust bowls leaked like a sieve, $1200.00 worth of work and parts down the tubes. As I understand it, later castings are actually better.
What ever you do good luck.
What ever you do good luck.
moper
Well-Known Member
If you haven't ported a few, then the best bet is to avoid trying to max them out. You can get good numbers with limited work around the spots that can be thin. You should also be familiar with identifying a core-shifted head. They're common and will affect the thicknesses. Stay away from reprofiling the short turn, be careful around the sides of the guides in the bowl areas. You cannot raise the roof too far without going through.
skrews
Well-Known Member
Have them crack checked (magnafluxed) before doing anything.
STRorange
Well-Known Member
That was bad luck Mr.Burch as the same thing happened to me too!
So I have cut the offending 'J' head into pieces to find out what went wrong?
The main cause of porosity is internal rusting, this is a symptom of leaving heads on the engine, but dry.
They seem to condensate/corrode more than taking the heads off and storing in a dry place.
Then they go thin just under the seat area by the intake port where they pair up.
John
So I have cut the offending 'J' head into pieces to find out what went wrong?
The main cause of porosity is internal rusting, this is a symptom of leaving heads on the engine, but dry.
They seem to condensate/corrode more than taking the heads off and storing in a dry place.
Then they go thin just under the seat area by the intake port where they pair up.
John
STRorange
Well-Known Member
As you can see even with a heavily ported head there is still plenty of 'meat' in most places, just not in one area!
between the intakes...
PRH
Well-Known Member
Do you have to run OE castings?
Decide how much power you need to make, then figure out how much porting that would require if using OE heads.
If it’s a substantial amount of porting, and you’re not experienced at it, I’d look at an alternative solution.
Basically, if you’re new to it, I’d try and limit the work to a “good” bowl blend, and live with the results....... or pay someone to do it.
High effort porting jobs from novices often don’t end well.
If you don’t “need” to run stock heads, but want to make some power...... you’d be better off in the long run getting aftermarket heads.
Decide how much power you need to make, then figure out how much porting that would require if using OE heads.
If it’s a substantial amount of porting, and you’re not experienced at it, I’d look at an alternative solution.
Basically, if you’re new to it, I’d try and limit the work to a “good” bowl blend, and live with the results....... or pay someone to do it.
High effort porting jobs from novices often don’t end well.
If you don’t “need” to run stock heads, but want to make some power...... you’d be better off in the long run getting aftermarket heads.
Thanks for the pics I'm doing x heads and learning. Trying not to get too thin.
Any more pics? Those help me wrap my head around "stuff"
Any more pics? Those help me wrap my head around "stuff"
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