I Might Have Found Something Pretty Cool.....

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qkcuda said:
How many cc's are the stock open chamber heads?
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These measured 56 before being ported. I THINK that's about what the stock production heads are, I'm not sure. I haven't measured any of those yet. The only other one I've measured is the one on Vixen now that was milled heavily and it's 34CCs.
 
Another thing to keep in mind with these beasts is the rocker sweep on the valve tips. It's backwards from a V8. The valves point away from the rocker shaft on these engine, not towards it like on V8s. So that means the rocker sweep will begin a little on the inside of the center of the valve tip and continue towards the outside, unlike a V8, since on the slant 6, the rocker tip is getting closer to the valve stem, instead of farther away. When I was checking the sweep, it took me a minute to recognize that. lol
 
Just don't let this thread die here ...
I really want to know how the engine runs once complete .
Are you going to maximize quench and comp. ratio ?
 
RustyRatRod said:
These measured 56 before being ported. I THINK that's about what the stock production heads are, I'm not sure. I haven't measured any of those yet. The only other one I've measured is the one on Vixen now that was milled heavily and it's 34CCs.
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the slant heads combustion chambers that I have cc'd are all in the 57-58 range, those have all been the newer peanut heads. One cc could be in the choice of sparkplugs, filling technique.
 
mbaird said:
Just don't let this thread die here ...
I really want to know how the engine runs once complete .
Are you going to maximize quench and comp. ratio ?
Click to expand...

I'm going to maximize both for what I have, yes. The block will get decked .055" for zero deck height. Pistons have a 14.5CC dish and heads are 59-60CCs. I woulfn't mind finding a thin steel head gasket, but not a deal breaker. With a .040 gasket I get like 9.1:1 which is about where I want to be. I didn't want to end up with 175 PSI cranking pressure like this engine I am running now.
 
Just as info, I've CC'ed two 79 peanut heads before milling them. They were both very even 60 CC's on each chamber before milling, and about 54 CC after.
 
Rusty, I had to swap head gaskets around based on my cam and piston clearance.
Do you have a copper gasket?
The one I have here is around .040, close to the perm-a-seal composite.
My steel was .020.

I know as you close in on the build you will figure that out.

I was just re-reading this thread, pretty darn cool.
I noticed the supports on the number 1 and last rocker shaft support.
Never noticed that before.
 
Hyper_pak said:
Rusty, I had to swap head gaskets around based on my cam and piston clearance.
Do you have a copper gasket?
The one I have here is around .040, close to the perm-a-seal composite.
My steel was .020.

I know as you close in on the build you will figure that out.

I was just re-reading this thread, pretty darn cool.
I noticed the supports on the number 1 and last rocker shaft support.
Never noticed that before.
Click to expand...

I have since acquired several of the original stock thin steel head gaskets. They'll compress down to around .018 to .020. So that, plus about the .010 the pistons sit down in the hole will be quench.
 
RustyRatRod said:
I'm going to maximize both for what I have, yes. The block will get decked .055" for zero deck height. Pistons have a 14.5CC dish and heads are 59-60CCs. I woulfn't mind finding a thin steel head gasket, but not a deal breaker. With a .040 gasket I get like 9.1:1 which is about where I want to be. I didn't want to end up with 175 PSI cranking pressure like this engine I am running now.
Click to expand...
I wanted to bring this back up since I changed my mind on the pistons. I just couldn't go with the dish pistons. My original intent was to build a smooth idling engine, but I've grown to really like the lumpy idle the engine in Vixen has now, plus it pulls like a beast. So I'm going back with a similar camshaft and to do that, I swapped the flat tops back on. They have a 4cc single trough valve relief. That will keep compression over 10:1 like it is now, but I will have the benefits of a good quench with the closed chamber head and all the port work and bigger valves. There's no sense in using a baby cam and low compression with a head like this. Plus, I'll also have my Clifford header added too, so the next engine should be pretty perky. Here are the pistons I am going to use. They're the non turbo piston for the 2.2 Chrysler 4 cylinder. A really thick hyper piston. I had the 198 rods resized and had ARP rod bolts put in too. These will actually sit about .007" down in the hole at TDC. That, plus the head gasket thickness will produce a good quench number.

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0.007 in the hole is a hell of a lot better than the 0.180" I have and that's even after a 0.030 shave off the block deck
 
volaredon said:
0.007 in the hole is a hell of a lot better than the 0.180" I have and that's even after a 0.030 shave off the block deck
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Yup. That's what the 198 long rod and 2.2 piston enable you to do.
 
RustyRatRod said:
Here is a good closeup of the chamber. It is unmodified from the factory casting. It MAY have been milled in the past just for a clean up, but I don't think so. I'll know more and will post more pictures soon.

View attachment 1715687364
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You can still see the fingerprint from the gasket for the combustion chamber.... dude That's Cool Rob!
 
Ironracer said:
I want to say my 63 Dart GT two-door had one.... originally, now I cain't remember if it was replaced or not.
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Couldn't be original. The 198 was made from 70-74. It certainly could have been a transplant, though.
 
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