!@#$%^&*heads

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bigdemo1

bigdemo1

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With all this talk about heads,heads,heads man I'm getting more and more confused(and I,m not the only one)Is it possible for someone(knowledgeable) to go through all of it and maybe somehow string all the common questions together in one thread,it seems like there is as much bad info as good,exagerated flow numbers,do it this way not that,maybe pick some power levels and castings then explain some common corrections to acheive this.I don't know if this is possible,just maybe clear some confusion.Right now I don't know if I should have someone port my J's or buy W-2's or magnums or indy's 2.02's are good,don't need them,port match bowl blend,WHAT?
 
I agree with you brother. I have 2.02 valves in my heads and was told on another forum from the talked about person that I shouldn't have not went that route. I didn't think that sounded right. Or, does it? Hell, I have a headache.
I was always under the impression that larger exhaust valves were best to help move air more efficiently, or something along those lines. My car responds very well to the 2.02 valves and the porting that was done. I have no plans of changing this setup.
 
WHOOAOO,is what my 5 year old daughter said when she saw your car,now where can I get that done.
 
What are you building?

j heads can flow anywhere from stock 200cfm to 260-280cfm 'safely ported'

hughes claims 301 @ .600 lift with j heads for like 1300$

Really don't get all thrown off cause some guy screwed another, it's not the heads fault, it's the guy that wrecked them.
 
BD1, You're absolutely correct. Heads and mods to them are very confusing. The bottom line is what kind of an engine are you building and for what purpose.
I would say that any stock head on any engine would benefit from a little port matching, bowl blending, and the like. How far do you go? It just depends on the rest of your combination. Heads that flow a bucket load @ .600 lift won't do you a darn bit of good if your cam is a .485 lift Rv cam. By the same token,
a 13.5:1 stroker with a .650 lift roller would barely run with a pair of stock 302's bolted on. I am using extremes here but you can catch my drift. If you have a set if J heads I think they would work good on almost anything (except for a 273) Any mods you do to them will depend on the rest of your combo. Unless you are building a low budget machine, a basically stock rebuild for a driver, I would have them port matched and bowl blended. I don't think you can go wrong there. If your combination is more radical, then you could benefit from more porting and possibly bigger valves. Lots of cylinder head discussions end up at the maximum hp and torque level. Most of us won't enter our engines in a dyno contest so a lot of the info doesn't even come into play. Save yourself some grief and don't let the complexity
wear you down. I hope this helps, toolman
 
Porting and valve sizing is all about what you want to do with the engine, desired results. You really need to speak with someone that can figure out an appropriate set up.
 
I would like to try as much as I can myself.I like to learn by doing(mild porting might be fun to do)
 
bigdemo1 said:
WHOOAOO,is what my 5 year old daughter said when she saw your car,now where can I get that done.
Click to expand...
DusterDude72 did this for me and several other members on here. Give'em a PM he'll do one for you too. Cars is my favorite animated movie so I had to have it done to my car.
 
bigdemo1 said:
I would like to try as much as I can myself.I like to learn by doing(mild porting might be fun to do)
Click to expand...

It's a blast if you like to feel, smell and have the smell of a rusty ship in your nose every day!

It's fun if you don't do it for a living. Plenty of resources on the net about porting basics. Read, read, read. Short turn and pushrod pinch are two areas of concern on SB mopars.

I use an air grinder with some bits from McMaster-Carr. Probably have about $100 in grinder and bits. Have good lighting, ventilation and breathing protection will make life easier.

If you have someone local that can point out what to do or give pointers, you'll be miles ahead.
 
Every head is slightly different,I reccomend getting a junk head and either cutting or grinding through a couple of the critical areas to give you an idea as to how much is there.But,if you are conservative you should not have a problem and get quite a bit more flow,as for tools I like electric and use a makita die grinder,much faster but it takes some getting used to,also invest in a hegglesen e-tool or fab a similar tool up,it is a must have imo when doing the pushrod pinch area to get the max area without breaking through.Ive ported alot of different heads-mainly because I got stuck with whatever my buddy brought me,1.88valves,2.02s,some with slightly sunk valves,even 318 heads on a 360 with the stock 1.78/1.5s and it was fully capable of 12s,so as others have said it really depends on your combination.
 
I've got a set of junk heads here and access to a crankin big horiz. band saw and have a new hobart 1/4" variable speed die grinder so I might give it a try,who knows I probably can't do any worse than some recent photos I've seen here.I'd like a serious street motor,not like money is no object,but not on a super tight budget either,like I said buy or port just want the most bang for a 3200-3400lbs cruiser/racer.I've looked at every picture that I can,every bowl,pretty sure I understand how much to lay back the short turn as I saw a cutaway of this and it looks like blending out the ramp and continueing with the softer turn like the intake side of the bump has,getting rid of the steep roll,bowls look pretty straight forward 80% of valve seat?blend in pushrod to straight line of uncut intake port,blend everything else,and port match does this cover it on a J with good valve job with 1.88's
 
My .02 on this subject... If you are going to use as cast combustion chamber, or runners/ports (who knows how much variance, from chamber to chamber), as opposed to CNC'd heads, were you have a definate compression ratio and real (equal) flow numbers, from all 8 cylinders.
Otherwise it's a somewhat crapshoot, what works great on one engine might be just good on another.
 
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