Milling of a 810 casing W-2 head

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mbaird said:
@Duane If the open chamber is better for flow why did the later W2 race heads go to a closed chamber ? Or was that just those 2 heads ?
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Duane nailed it. Because the Chevy guys cry about quench like its death to an engine without it, Chrylser did the dirty and did it.

Same chamber as the W5 head and it is just nasty. The W5 you can weld up and help it a bunch. The W2 stuff you can't. You just learn to deal with it.

You can get quench with the open chamber heads. You just have to find a machinist who will do it the right way. Try and convince a life long Chevy machinist who has never built a Chrylser and done it correctly to stick a piston .050 or .060 out of the hole. Try that just once. Before I was doing my own machinist it damn near came to fists to get him to put my stuff out .017 and when I finally convinced him he was ignorant I made him stick them out .040 so the CR was where I wanted it without wrecking the heads.

He is doing doing engine work today and is still a dumb ***. Other people read stuff like this and then try and get it done correctly. I know he is still a dumb *** because I took a call from a member of a different forum about getting the block milled and he was using the said machinist. I told him to go back in there, face to face and tell him what you want, or you'll beat his dumb ***. He will either do it, or send you away. Either way, you can't lose. Either he will do it correctly or I can tell you where to get it done correctly.

Said dumb *** did it, but bitched about it to the point he almost took an *** beating anyway.
 
yellow rose said:
Duane nailed it. Because the Chevy guys cry about quench like its death to an engine without it, Chrylser did the dirty and did it.

Same chamber as the W5 head and it is just nasty. The W5 you can weld up and help it a bunch. The W2 stuff you can't. You just learn to deal with it.

You can get quench with the open chamber heads. You just have to find a machinist who will do it the right way. Try and convince a life long Chevy machinist who has never built a Chrylser and done it correctly to stick a piston .050 or .060 out of the hole. Try that just once. Before I was doing my own machinist it damn near came to fists to get him to put my stuff out .017 and when I finally convinced him he was ignorant I made him stick them out .040 so the CR was where I wanted it without wrecking the heads.

He is doing doing engine work today and is still a dumb ***. Other people read stuff like this and then try and get it done correctly. I know he is still a dumb *** because I took a call from a member of a different forum about getting the block milled and he was using the said machinist. I told him to go back in there, face to face and tell him what you want, or you'll beat his dumb ***. He will either do it, or send you away. Either way, you can't lose. Either he will do it correctly or I can tell you where to get it done correctly.

Said dumb *** did it, but bitched about it to the point he almost took an *** beating anyway.
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That’s true. Racers screamed for a closed chamber for quench and a easier route for higher comp. Now try and find low compression forged slugs for a supercharged engine. LOL!

Ether way, in building a W engine, who cares about mileage and fuel concerns? It’s a fresh build and you will build accordingly. Compression builds torque and HP but without a decent ratio for use with an increased cam duration, the engine becomes less efficient and effective.
 
Doesnt a hemi actually have 2 quench pads due to the dome matching the chamber angles ?
 
Then I’d say yes if you can get the piston within .050 and still have a pocket to which the all the squeeze can rush into.
But I really don’t know....
:lol:
 
mbaird said:
Doesnt a hemi actually have 2 quench pads due to the dome matching the chamber angles ?
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This comes up sometimes.

It's actually squish on a Hemi like that and not really quench. Squish like you would account for in two stroke combustion chamber geometry.

So it's not the same.
 
I should mention too, that it was explained to me that it is not the quench pad side that hurts the flow. It's opposite side of the chamber pad. A closed chamber has a very abrupt curvature there that kind shrouds the valve. The open chamber on this same side has a nice gradual curvature that allow the air to get by the valve better. At least that's according to Ryan J. That's also part of the difference in the two Indy heads.
 
Right! And that’s why am open chambered head is better.
 
Duane said:
I should mention too, that it was explained to me that it is not the quench pad side that hurts the flow. It's opposite side of the chamber pad. A closed chamber has a very abrupt curvature there that kind shrouds the valve. The open chamber on this same side has a nice gradual curvature that allow the air to get by the valve better. At least that's according to Ryan J. That's also part of the difference in the two Indy heads.
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That's true. But, that abrupt edge above the valve seat without the quench area also plays hell with air flow.

I'd try and explain it, but I'd mostly get it wrong. It had to be explained to me. I just know what I found.

It has to do with exit losses on the chamber side of the valve and that area when machined away or filled in in bad for that.

I bought a junk W2 head from a guy for 10 bucks (he was junking it but when he found it I wanted it he beat me up for 10 bucks) and that's the head I milled away. Flow loss was bad. I learned how to fix most of it, but with cast iron it's a real bear to correct if at all.

That's why when I bought my W5 heads I new the chamber was going to need a ton of work. In fact, the guy who explained the exit loss and other things said not to buy that head just because of the chamber.

But I can't say his name for the public humiliation of being called a name dropper.
 
Dang! This is an awesome thread.
I was really debating about using cast iron 80's technology open chamber heads....
 
mopfried said:
Dang! This is an awesome thread.
I was really debating about using cast iron 80's technology open chamber heads....
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That W2 head is MILES ahead of any, and I mean ANY 23 degree GM stuff. The only GM 23 degree stuff it won't outrun is the raised runner stuff and that's what the W5 was for. With work, that's a pretty bad assed head on its own, it just takes a ton of work and quite a bit of welding to get it where it's happy.

BTW, I forgot to mention that when flowing on a bench, you have nothing in the hole. When the head is on the engine, and you are at the two most critical times in the power making cycle, the opening of the intake valve, and then what is called the overlap triangle, the piston is making up the bottom of the combustion chamber.

Anything you can do to get the flow happy at that time, you'll make more power. If you just think about what that looks like in your mind, you can develop a picture about why a later opening intake cycle with a quicker lobe can make more power, idle better and cleaner and have more low end power without a loss in top end power.

The last thing you want is to open that intake valve any earlier than you have to for your RPM range. For one thing, the piston is right there, in the way. And as the piston is moving around TDC and you open the valve earlier than needed and you'll have the piston pushing the intake charge right back up the port.

Here is another example of why Rod to stroke ratio is important, especially in induction limited combinations. IMO, a higher rod/stroke ratio can always use a quicker lobe, because the piston is hanging around TDC longer. That means what is ok for a lobe for a lower rod/stroke ratio may be not as good as it could be for a higher r/s ratio. That's because the overlap triangle looks different when overlaid with the motion of the piston. That's why cam timing that moves the intake opening and exhaust closing around to get the LSA wider to "correct" what is thought to be an idle issue can be a bad thing for power.

I like to see a very leaky overlap triangle rather that a triangle that looks more like a cam lobe than a triangle.

All this stuff matters if you want to get the most for your dollar. It doesn't cost any extra to sort this stuff out while you are building your combination. It gets expensive when you have to fix it after you've already settles on the hard parts.

It all matters.
 
I have pocket ported a few Mopar heads with templates, but never have had them on a flow bench. I have done a lot of two stroke reed valve motors way back and i can picture in my mind what your saying.
 
Oh so true on that cam suggestion. I’m on board with that in this arena. Not so much for a mild street level performance rides. A serious street strip effort can do with a great cam though.

The quicker that valve opens, the better! Just imagine a wall of air & fuel coming in like crazy. And that larger in that un-obstructed port! WOOOOOOO!
 
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