Chevy valves-J heads rocker geometry tricks

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well the desk guy misspoke, I have 1.80 spring height and a stock mopar stem height with the .100 longer chevy valves, sweet.

Moper, why would you be surprised?
 
345man said:
thats some good head work, it don't matter who done them, how much does a job like that cost?
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Those heads are over $2000

340sFastback said:
Probably more then a set of new Edelbrocks.
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Yes, More then a set of eddys but most people that are using Greg Gessler or Dwayne Porter for a set of heads like those are likely using them for a stock appearing car and Eddy's just wont fit the bill.

I like the stock look and would probably put money in to stock heads before running a set of aluminum.
 
I'd be surprised if they move that much air because it's virtually impossible to do on iron without moving the pushrod over and making the pinch larger.
 
I would be happy with 260cfm on the intake while the exhaust is cake to get 180-200.

Shady dell sells j heads in the 265cfm range right now If someone wanted them, and they don't tube the push rod holes.
 
Chuckles, any time you feel you have something to add, please do. I missed your intellectual comment. I thought the target was 280? Why was it at .500? What did the rest of the test look like? I'm assuming they were tested beyond .500. Also, what is the port volume? Who tested them? And I think I said I'd be impressed, not it's impossible. Dont know Gessler, but there's a ton more guys I don't know than people I do. Especially if he's FAST or Super Stock, which are not my forte nor much interest to me. I'd love to hear anything you care to comment about if you can keep it clean. How about an idea for addressing the geometry issue posted about? Or is to hard for you to dig up internet-based fixes for that?
 
I am in agreement with you Moper. NOT impossible,.. but not easy to get 280+ out of the factory castings. Most of the stock LA castings I do go in the 260-270 range. Using 2.020 .375 stem. SS Mopar valves. Actually 270 cfm isn't really difficult but above that level takes so much more work(time). The law of diminishing returns comes to mind. I did a set for a FABO member last year and they pulled 283 on my bench...but I had SO VERY much time in them. Some of the relocated pushrod heads I have done go over 290. But they have W2 volume and are a big port. They will flow gangbusters on the intake side, which puts them out of ratio on the exhaust side. That can be helped by running a split pattern cam. These relocated PR heads are the ticket for someone wanting to stay 'stock' appearing and have flow approaching W2 castings. Not cheap but they do work. These new EQ heads are promising. They will flow over 250 with the 2.020 valve as cast. You would have to believe they are capable of at least 275-285 range or more with some work. Thinking of picking up a set to massage. I will report if that happens. I Just wanted to throw that out there.

Terry
 
good read... ha ha

well the moral of the story before polishing and back cutting is...
.100 60 - 46.4
.200 132.8- 93.3
.300 193.3- 134.3
.400 241 - 166
.500 270 - 174.2
And after minor touch up, back cutting and polishing....
.100 75 52
.200 142 101
.300 200 141
.400 249 169
.500 278 180
.530 281 184
.600 248 187

When you are broke like me and can only do things a lil at a time...
yes, it's completely worth it.
The catch when doing this 11/32 valves thing, with big lifts especially, is to check geometry BEFORE YOU CUT STEM HEIGHTS. lol
I spaced it & learned the hard way.

These heads are running now on a 410 that'll pull yer head off just the rolling on throttle.
 
Do you think the valve knows what head it's in? Or cares? Out of curiousity... You do know Magnums and Edelbrocks and aftermarket Magnum based heads all use 11/32 valves... right? Think there's a reason for that? The tulip mopar type valve helps when the bowl and port aren't that good. They help air turn when the port doesnt. But a thinner stem is less "in the way", less friction in the guide, and lighter... and the nailhead valve will flow more when the port can be shaped properly.
 
moper said:
Do you think the valve knows what head it's in? Or cares? Out of curiousity... You do know Magnums and Edelbrocks and aftermarket Magnum based heads all use 11/32 valves... right? Think there's a reason for that? The tulip mopar type valve helps when the bowl and port aren't that good. They help air turn when the port doesnt. But a thinner stem is less "in the way", less friction in the guide, and lighter... and the nailhead valve will flow more when the port can be shaped properly.
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This is true,Ive built and know of alot of mopar heads with chevy valves,hughes uses them as well in alot of their head builds,also the flow numbers have been good with no significat drop above .500 like alot suggest,its about proper porting.
 
360Z28 said:
chevy valves for flow on LA heads eh? tsk, tsk, tsk. this cracks me up that people use chevy valves looking for that voodoo cfm flow.
they punk out and buy cheap chevy valves instead of going with something like ferrea mopar valves and expect that there will
be know problems. lol. they make undercut valvestems for a reason.
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what exactly makes a valve a chevy or mopar valve ? Doesnt ferra also make valve for chevys ? Kinda a dumb statement.
 
AdamR said:
You know, This is kinda a funny argument to be having with someone who owns a CAMARO! Why is it ok to put a Mopar motor in a Camaro but you shouldn't run a Chevy valve in a mopar head ?

Do you think some one will see the valve and say, Hey, Thats a chevy valve in your mopar head.
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Way too funny.
 
what did I miss? lol

Wow, if a port isn't designed to flow past a certain lift due to turbulence then the next best thing besides starting over and redesigning the port all over again, would be to get all the sht outta the way [beside the valve head cause it's max lift/flow or corking effect is what's keeping the fps down so it doesn't break up completely] would be the stem or nilling down it's size.

Now a 3/8 valve is or can be considered more durable, but compared to what..a stock 11/32???? how bout an 11/32 stainless race valve?
Now like someone already mentioned the skinnier equates to lighter, we all like lighter parts as long as they hold up right?
I remember asking hughes what's the diff between their head work and others, they said.. ''well..we start with a 11/32 valve stems which net 7cfm on our bench'' the rest of bits that go with are dime a dozen readily available 'chevy dimension parts' NOT chevy parts, for all are after market 'manley' sold through 'engle' with comp retainers/super locks which are universal and work on chevy ford mopar etc.....
Does a 11/32 make a mopar? no.
But do they help with making more power in modified form? YES.

say... do you pick up flow when you narrow down the guides?
 
All it takes are guides, valves that cost lees than mopar valves, and run of the mill seals, locks and what ever spring that works.

You'd buy all that sht anyways when rebuilding performance heads.

You're alright Z, but when it comes to 'punking out'.. I'm not the one with the whole car thats a chevy, just some aftermarket valves that happen to share a chevy 11/32 stem dimension.
 
We've been putting 1.94 chevy valves in mopar heads for a long time. Nice midway compromise between the 2.02 adn 1.88 valves.

Anything from 5/16 and up.
 
360... If you think there is no gain for simply running a smaller stem, you really need to do some more testing and less reading. In terms of the smaller stem being harder to get the geometry right on... you're right. But avoiding using them because you can't get the rocker shatf and seat oriented right is another one of those "less reading and more doing" deals too.
 
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