furrystump
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Dwayne Porter got about 275 @ .550 lift average out of my X heads. IIRC. Without moving the pushrod pinch that is a pretty serious effort for an X head.
340 Max HP Potential with X/J heads?
- Thread starter moparodbuster
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MOPAROFFICIAL
Oogliboogli
I get that too and none of what's mentioned includes moving the push rod or re locating the pinch. We are talking stock rocker stuff.
moper
Well-Known Member
Everybody's talking about porting, in a couple cases expensive porting. So I get back to "as cast it will struggle". So you can save $1K, to get an open chamber and 50lbs more of the wrong weight bias, and then pay to get them to work for your application. I've done it. I've made very good power with them. But as far as recommendations - buy an aluminum head and build with it in mind.
I am not like most. I enjoy seeing a stock, iron head made to flow by someone that knows what they are doing. The simple fact is, they CAN be made to flow. Everything costs. You just decide where you want to spend and go from there. It takes real experience and talent to make old iron flow well enough to support a stroker and some people can do it. I have great respect for that.
Thanks for mentioning that and vindicating me and my past mentioning of how a factory head can not only be a good performer and ported well but a truly viable alternative to aluminum heads.
But yet everybody cries “HEAVY”, “ALUMINUM “, “BETTER FLOW” and so on.
With 260+ cfm available, shiiiiiiiiiit, if you can go fast now....
LMFAO!
The only question is, how much you willing to spend to get the iron to flow. It's gonna cost a bunch to reach #'s to support a stroker. no question it can be done.
MOPAROFFICIAL
Oogliboogli
There are a ton of people/racers that do it themselves. If you want it done and done right... that's how I ended up doing this.
It’s a catch 22 since you all ready have the iron heads vs. spending the current 718.50 per head (Edelbrock) and then spending more on them.
But what is it we are doing and do you need the aluminum on the street? I’ve seen more lame *** street builds that could have performed excellent with mildly prepped iron heads for cheaper money than the OOTB $1427 parts. Not to mention correction costs. Never mind porting costs. And since I’m just throwing imaginary money out the window, let’s make sure the heads out flow the iron heads with a CNC job.
Hey! IF your absolutely Need the aluminum......
Then by all means, go get your aluminum. You state (act) like your going to drop $2500 on iron heads to fail. Seriously you can’t be serious and if you are, stop bending over at the desk of THAT head guy.
In order to get the aluminum heads to perform and make that 4.00 arm small block perform at its best is going to cost a bundle anyway and it’s still gonna fail unless your looking at a Victor/W7-8-9 head where your spending (on the Victor) at least $1670 PER HEAD! And they still need to be checked out.
And when you say the aluminum heads, that GOD DANM field is wide open to an overkill degree. Just what head are you going to choose? There’s always a better head over an iron head. But what is it YOUR DOING! WHAT ARE YOU DOING?!?!
I have had this debate to many GOD DANM
MUTHA FUCKIN times to continue with a narrow mind knot head on a street build to enjoy and not race.
and plenty have screwed them up.
Jezz uzzz H! Tell’em!
WT MUTHA FREAKIN F!
This guys have got to be kidding me/us.
The OP is looking to save a few bucks and he just carries on and on even with decent supporting FACTS in front of him.
If I had only a grand to spend on heads I wouldn’t be in debt on a set of heads that needed work from there highly touted OOTB ready state!
LMMFAO
Holy moly!
MOPAROFFICIAL
Oogliboogli
I understand, that's learning. Funny thing is... if the heads are junk like some rattle off... then who cares.
moparodbuster
moparodbuster
From what I gather, the 915 J's aren't going to flow much different than the eddys once ported so I've gone ahead and bought them for $300. They are untouched from factory from 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. Thanks for the help! I'll post a new thread with this question to maybe get some different ideas.
moparodbuster
moparodbuster
It's a street race, full weight, restoration running pump gas, 4.30 diff, reverse manual 904, ss springs, street slicks, stepped tti's, full length dual 3" out the back
furrystump
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Dwayne is on moparts, but remember this is how he makes a living. He is a very nice guy and answered all my not so smart questions. In 2014 Using my heads and installing new 2.055/1.625 ferrea valves new springs, guides, tool steel retainers, hardened exhaust seats and full porting was about $3000-$3500 a pair. IIRC, but I could be off a bit. I’m old! 
cast iron has its place, but if I wasn’t required to run it I would have done aluminum head.
cast iron has its place, but if I wasn’t required to run it I would have done aluminum head.B3422w5
Well-Known Member
Dwayne is on moparts, but remember this is how he makes a living. He is a very nice guy and answered all my not so smart questions. In 2014 Using my heads and installing new 2.055/1.625 ferrea valves new springs, guides, tool steel retainers, hardened exhaust seats and full porting was about $3000-$3500 a pair. IIRC, but I could be off a bit. I’m old!
Dwayne is a friend and spec’s most of my cams. He told me about your heads. You race in a supercar class, correct?
furrystump
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Yes, a small block in a big block world!
MopaR&D
Nerd Member
I mean, if they've ever ported a set of heads off any old American 2-valve pushrod V8 the same basic rules apply. I don't think there's much specific to Mopar heads compared to Chevy or Ford small blocks that makes porting them different than the others... Mopar heads just have better port shapes, valve angle etc. from the factory than the Brand X stuff
MOPAROFFICIAL
Oogliboogli
Work the Straight wall, guide, guide kink, roof and bowl. Do a good throat cut and blend it to the bowl near the roof.
You can blend the throat cut at the short turn at/near the peak/top, but unless you know what you are doing... leave it at that. With flow increase and not enough cross section...in comes the air speed.. and with too much the port goes turbulent and flows less!
You can blend the throat cut at the short turn at/near the peak/top, but unless you know what you are doing... leave it at that. With flow increase and not enough cross section...in comes the air speed.. and with too much the port goes turbulent and flows less!
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To the op.
If you don't have the skills or tools to port your heads. Just ask your machinist to do a good 3 angle valve job. when you get them home, remove the intake valve and smooth up the bottom cut in the throat. This is the single biggest JUMP in CFM that you will get in porting the head.
Yes there is a lot more HP potential hiding in them heads but it take a lot of time and patience to get out of them.
From that point i would jump to the iron RHS heads.
or if you must eddies that need to be sent to you machinist to have some clean up done for longevity.......
Just my .02 sence
67autocross
A new iron curtain drawn across the 49th parallel
I just had a 4 inch crank show up this week, I will throw it in a 340 with some 10:1 pistons, 2.02 J heads that flow 250ish and a mid 500 lift solid cam and I will post the results
MOPAROFFICIAL
Oogliboogli
W/2.02...When you raise the port roof enough n trim up the guide, you can almost leave the short turn barely laid back at the top after a good steep throat cut and have 260's. You have venturi it properly in such case. That's why that set of mine looked almost factory on the turn. W&C
67autocross
A new iron curtain drawn across the 49th parallel
Try it! you will like it!!
just don't expect it to act like a 340 any more.
I have used the same heads,intake and carb on a 340 bottom end and have the dyno sheet for comparison...of course the cam will be different
skrews
Well-Known Member
Stock J heads vs OOTB RPMs on your combo will be a big difference. That being said both heads are too small to really let that motor run to its potential. With the stock J heads that thing will be done very early. Now with mild to moderate competent porting the J heads will run with the RPMs, and heavily ported will run even better.
I'd be asking myself how far ahead will I be if I paid now instead of later. If it were me I'd wait and see what Trickflow has to offer this winter. LOL I have a 50,000 dollar car that is worth 20 after fooling with it for the last 40 years.
So I say spends your money once, wait if you have to.
So I say spends your money once, wait if you have to.
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