Most popular head casting/chamber design

-
MOPAROFFICIAL

MOPAROFFICIAL

Oogliboogli
Joined
Jun 1, 2016
Messages
13,345
Reaction score
17,363
Location
Popcorn stand
I have a few slant 6 heads laying around, early , mid, late. I'm going to port , rebuild,flow and sell them. Couple will have big valves, one stock size. The stock size ported intake will probably flow around 175cfm@.500 when I'm done, the big valve versions in or around 190-200 cfm.
I wouldn't wanna waste time on the wrong heads. I do plan on selling these, fully machined, valve job, guides, and springs for .500 lift stuff. Inquire later if you're interested in one.

Let's hear which casting and why, thanks.
 
Iirc they were all about the same but the later castings had a better chamber according to slant six dan.
 
According to this, the smiley face one is the one to get.

Revised SL6 Combustion Chamber

One of the pictures from that site.

cchambers-smiles.jpg
 
Correct, the later ones with the quench pad hugging the exhaust valve more closely are better, but none of them are great. With a 225, the pistons need field glasses to see the deck, the most You can hope for is a really good swirl discharge from the intake port. Generating squish with zero-deck pistons, and a milled/filled chamber puts You into race squeeze territory, which is fine if that's where You're headed.
 
Killer6 said:
Correct, the later ones with the quench pad hugging the exhaust valve more closely are better, but none of them are great. With a 225, the pistons need field glasses to see the deck, the most You can hope for is a really good swirl discharge from the intake port. Generating squish with zero-deck pistons, and a milled/filled chamber puts You into race squeeze territory, which is fine if that's where You're headed.
Click to expand...
Now that the 1.70/1.44 have dried up, what's the next off the shelf valve to make work.
Ford valves.....or 1.72 sbc/jeep
Stock length is 4.78
You could grind some off the stems, if you needed to. Hmm
Which would you want, less than stock by .111 or over by .150+
 
Killer6 said:
Correct, the later ones with the quench pad hugging the exhaust valve more closely are better, but none of them are great. With a 225, the pistons need field glasses to see the deck, the most You can hope for is a really good swirl discharge from the intake port. Generating squish with zero-deck pistons, and a milled/filled chamber puts You into race squeeze territory, which is fine if that's where You're headed.
Click to expand...

All depends on which pistons you use.
 
MOPAROFFICIAL said:
Now that the 1.70/1.44 have dried up, what's the next off the shelf valve to make work.
Ford valves.....or 1.72 sbc/jeep
Stock length is 4.78
You could grind some off the stems, if you needed to. Hmm
Which would you want, less than stock by .111 or over by .150+
Click to expand...

Ford 300 valves are close enough you don't have to grind anything and they have smaller 11/32 stems for a little more flow.
 
RustyRatRod said:
Ford 300 valves are close enough you don't have to grind anything and they have smaller 11/32 stems for a little more flow.
Click to expand...

I offer you this.

140/150 CID ford ranger 1.73 head, OL 4.788, stem early yrs are .341...late .241 , multi groove=2

GM's 252 cid 1.71 head OL 4.7135 stem .34170 single groove

4.6 ford 1.75 head OL 4.756 .241 stem

There are a few valves out there that will work.
 
MOPAROFFICIAL said:
Now that the 1.70/1.44 have dried up, what's the next off the shelf valve to make work.
Ford valves.....or 1.72 sbc/jeep
Stock length is 4.78
You could grind some off the stems, if you needed to. Hmm
Which would you want, less than stock by .111 or over by .150+
Click to expand...
In '89, I used BBM 1.74" exhaust valves on the intakes, and 1.41" AMC exhaust valves which were a bit long & needed the springs shimmed. There is another thread here about a build using Ford 2300 valves from the later models w/7mm stems etc.
 
MOPAROFFICIAL said:
I offer you this.

140/150 CID ford ranger 1.73 head, OL 4.788, stem early yrs are .341...late .241 , multi groove=2

GM's 252 cid 1.71 head OL 4.7135 stem .34170 single groove

4.6 ford 1.75 head OL 4.756 .241 stem

There are a few valves out there that will work.
Click to expand...
With the limited real estate in the port, the small stems are a great idea for multiple reasons.....................
 
MOPAROFFICIAL said:
I offer you this.

140/150 CID ford ranger 1.73 head, OL 4.788, stem early yrs are .341...late .241 , multi groove=2

GM's 252 cid 1.71 head OL 4.7135 stem .34170 single groove

4.6 ford 1.75 head OL 4.756 .241 stem

There are a few valves out there that will work.
Click to expand...

Do you think any of those are better?
 
RustyRatRod said:
Do you think any of those are better?
Click to expand...
I'm not sure if I would use the word better but I do know that they're real close to the the overall length and head diameter, and they have real skinny stems. After that it's all about finding ones with a single or a double Groove that you can get locks for that fit retainers readily available or at least for the spring we're using.
If you go to engine Pros website and get their catalog of all their valve size listings they offer a stainless single Groove version of one of these valves, I can't remember at the moment which one it was..
 
We'll go with whichever ones you say.
 
RustyRatRod said:
All depends on which pistons you use.
Click to expand...
It would have to look like an old TRW blower piston, with a dome at the quench pad end and a waay below deck crown level on the other end. Even at that, by the time You fill/mill the chamber to give a gasket plane surface for an effective squish to accelerate the burn,..the squeeze will be up there. The long-rod/Wiseco piston combo will be very high if it's at -0- deck with said modded head. I honestly don't know how much the compact chamber will allow w/a fast burn because I don't know anybody that's run an effective squish slanty.
 
You must log in or register to reply here.
-

Back
Top