Intro to a port job

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What about it? It's a remnant from the factory machining. J.Rob
Some people say that you need to sink the valve a little to get ride of that factory.......Flaw???
Others say you will loose bottom end torque if you remove that groove.
Any thoughts on that?
 
What about that ridge around the valve seat ?
Yes. Looks like a basic 3 angle vj to me too.
You can lay another stone down, at the same time some angles and size... help flow in the wrong direction.
Theres a cutter that brings 5 angles and puts nice shallow bowl around the intake where the chamber shrouds and up into the plug boss a hair .050 wide angles 75,60,45,30, radius top.
Its said the ledge on the exhaust 'chamber side'..to leave the lil ledge near the chamber. I'd say its dependent on what's done up to that point and where the seat is but mostly accurate.
As I said in some other thread...on the intake.. The top cut, lip, that makes some guys drool is not the end all. Remove the lip and put the seat down more and down you have more influence with the valve job. That's not the end all either, but it does change the curve a lot. I like a deep 60. Ram does good on that as far as I can see. I'm waiting on my stone to do 60, atm only on the exhaust.
When you start doing it yourself..you begin to see how little effort the head guy st the local shop puts into your valve job. It does not take long to lay a couple more angles if you have the pilots and holders to jump around.


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Some people say that you need to sink the valve a little to get ride of that factory.......Flaw???
Others say you will loose bottom end torque if you remove that groove.
Any thoughts on that?
On the exhaust it effects flow. They say the ledge helps. I've never heard that on the intake side though. I'm open to learning if you can share your findings.
Putting the intake down some and bowl cutting around it works if the turn wasnt butchered before hand .
 
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The theory that was relayed to me is that it was done to better control reversion and that the groove or flat spot around the head of the valve, on the seat, of the head, was to make the air bounce back into the port instead of flowing back up the intake, on the valve over lap.

The groove on the exh side??????
 
The theory that was relayed to me is that it was done to better control reversion and that the groove or flat spot around the head of the valve, on the seat, of the head, was to make the air bounce back into the port instead of flowing back up the intake, on the valve over lap.

The groove on the exh side??????
"Back into the port and not the intake"

Hmmm.


The exhaust, simple..like water coming down a fall over rocks. Too much removed around the exhaust valve, chamber shroud side hurts.
 
"Back into the port and not the intake"

Hmmm.


The exhaust, simple..like water coming down a fall over rocks. Too much removed around the exhaust valve, chamber shroud side hurts.
help me out a little here
Are you saying that removing the flat spot around the exhaust hurts flow, or that sinking the valve to remove that flat spot hurts flow.
I can not see how removing the flat spot with a 15 0r 30 would hurt the flow..... should help right?
 
help me out a little here
Are you saying that removing the flat spot around the exhaust hurts flow, or that sinking the valve to remove that flat spot hurts flow.
I can not see how removing the flat spot with a 15 0r 30 would hurt the flow..... should help right?
The angles are good, but removing too much material at the chamber around the exhaust, for me at least showed no gain and a small loss. I've put a junk valve in, ground the lip out smooth and lost some lower lift flow. Key is some chambers are more shrouded than others, so working there can be a gain on some heads.. then a nothing on others who arent plagued by shrouding
 
What about it? It's a remnant from the factory machining. J.Rob

Not good for performance , I`m sure you`ve done a before and after on a flow bench , those are killers for flow.
My buddy is a great head man (ex 18 time national record holder) and has a state of the art valve/head machine , I saw personally the diff , between that lip , about the size of a clipped heavy fingernail on the flow bench , then w/o it , was almost unbelieveable.
I wouldn`t let anyone use stones for a valve job anymore .-----On any head of mine.. I guess a stock engine type build would be all right for some uses tho.
Just me .
 
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Not good for performance , I`m sure you`ve done a before and after on a flow bench , those are killers for flow.
My buddy is a great head man (ex 18 time national record holder) and has a state of the art valve/head machine , I saw personally the diff , between that lip , about the size of a clipped heavy fingernail on the flow bench , then w/o it , was almost unbelieveable.
I wouldn`t let anyone use stones for a valve job anymore .-----On any head of mine.. I guess a stock engine type build would be all right for some uses tho.
Just me .
People might say the same about you .lol
Just kidding ya. That's fine. To each his own. Everything is specific, you can get carried away ,open too much of the chamber side around the exhaust and screw **** up. Nothing wrong with stones, if you know what you're doing and check your work. Honest to God truth I've had more bad valve jobs done with a serdi than stone. Chattered by an elephant operating the arm.
 
People might say the same about you .lol
Just kidding ya. That's fine. To each his own. Everything is specific, you can get carried away ,open too much of the chamber side around the exhaust and screw **** up. Nothing wrong with stones, if you know what you're doing and check your work. Honest to God truth I've had more bad valve jobs done with a serdi than stone. Chattered by an elephant operating the arm.

Not here -------I was amazed at the post condoning sinking the valves too , doesnt hurt a hemi elephant much, if any , but a wedge , not no , but hell no..
 
Not here -------I was amazed at the post condoning sinking the valves too , doesnt hurt a hemi elephant much, if any , but a wedge , not no , but hell no..
Lol well putting it down some doesnt hurt ****.
Sinking it does. Yes.
Post one of this thread shows what sinking it looks like, it sucks. Putting the seat down some to get material for a 5 angle serdi... is EXACTLY the way to do it if you are.

Wording can really confuse things.

I guess I was trying to say is i can get the flow with a variety of valve job profiles, so if others have a problem...its them.
 
Lol well putting it down some doesnt hurt ****.
Sinking it does. Yes.
Post one of this thread shows what sinking it looks like, it sucks. Putting the seat down some to get material for a 5 angle serdi... is EXACTLY the way to do it if you are.

Wording can really confuse things.

I guess I was trying to say is i can get the flow with a variety of valve job profiles, so if others have a problem...its them.

In all honesty , what I know about this stuff is hanging and helping my friend do my heads ,and asking questions , he showed me the things I mentioned on sbc heads, and a long time ago hemi heads that i had, and even the cnc`d raised port heads I have now.
A diff machinist sunk the hell out of the valves in this car , I think the bastard did it on purpose , or went to sleep doing it , but iit didnt hurt them at all----------
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In all honesty , what I know about this stuff is hanging and helping my friend do my heads ,and asking questions , he showed me the things I mentioned on sbc heads, and a long time ago hemi heads that i had, and even the cnc`d raised port heads I have now.
A diff machinist sunk the hell out of the valves in this car , I think the bastard did it on purpose , or went to sleep doing it , but iit didnt hurt them at all----------View attachment 1715598548
What I'd give to have that body style. I was close 2002, should have. Cant find them now. I hear you on the stuff your friend told you there's a lot of different things for different heads some techniques you would use on a small block Chevy exhaust don't work on a sb Mopar for instance. I dont know everything, sometimes I mix up. I'll 'never' quit trying to learn something and if/when I find out diff.. I try to figure what was the differentiating factor, the culprit. Some things might not work because we did something wrong further down the tract, the turn, or the bowl, or throat cut. That's what keeps it interesting! Lol
 
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The intake is a holley strip dominator.
I had stated in another thread 'forgot which one' that when I flowed the strip dominator..it did 227 or 229cfm. That's incorrect. I looked at my papers last nite and it did 240 cfm bolted to a head that flowed a peak of 264cfm on that particular port. That was what would be no.2 cyl. Fwiw .
I worked the roof into the plenum just rounding it a fair amount, it only picked up 5 cfm to 245cfm. It needs a lot of careful attention to the runner.. or very little done and a spacer ...depends on your goal and skill set. Clay might say it needs welding...or that spacer we were talking about. @Jadaharabi
 
I think if I were less hon solo about it.. I'd just do a search for threads on them and spring board off what others already tested and determined.
 
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