Head Porting

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Slantsix64

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Started porting an extra 1968 head for my slant six. I found that the 1968 head vs 1979 peanut head was pretty much gasket matched versus my peanut 79 head which had offset matching of port and gasket.

This is what i has done so for i wanted to see where you guys think i should took more out or leave alone i dont want to mess this up. Im not trying to build a race car just trying to improve my top end with out sacrificing low end.
 
This is the intake

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Around the valve stem guide, can that lip be removed? or leave alone?
 
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I personally did not mess around with the guide you are way closer to the guide than I got. I wanted to leave as much material there as possible. All I did was round the edges off

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I personally did not mess around with the guide you are way closer to the guide than I got. I wanted to leave as much material there as possible. All I did was round the edges off

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Thanks for the pictures! yeah i know i didnt want to keep going and cause problems, Oh dang i didnt know you could go that deep into the casting around the intake guide
 
Thanks for the pictures! yeah i know i didnt want to keep going and cause problems, Oh dang i didnt know you could go that deep into the casting around the intake guide
That's just how they are made I didnt cut anything around the guide. My focus was around the bowl and opening up the bowl to the size of the valve guides and blending them down thru the ports
 
Btw these are 360 heads not slant 6 head I was just using them for reference about the valve guides. I'm not a professional this is my first set.
 
Dont grind the guide. Water is under there on one side ... .060-.080 thick there.

Raise/grind the roof some up to the guide, keep the port window gasket sized.... the walls can be widened some...the floor is really where the flow is. The turn needs laid back a ton.... it's not like a 360 head at all.

Not for the novice.
 
slant heads are cheap, but not as cheap as 360 heads! Lost of improvements in the floor of almost any head at the short side turn. some like the W2 raise the exhaust floor considerably.
head-crossection.jpg
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Dont grind the guide. Water is under there on one side ... .060-.080 thick there.

Raise/grind the roof some up to the guide, keep the port window gasket sized.... the walls can be widened some...the floor is really where the flow is. The turn needs laid back a ton.... it's not like a 360 head at all.

Not for the novice.
by floor you mean when the head is mounted ? i forgot im doing this with the hhead upside down lol
 
by floor you mean when the head is mounted ? i forgot im doing this with the hhead upside down lol
looked like u still had a little of the tonsils left , I`d take them out . LOOK at the area under the valve and think about it .
 
After the porting is done iam going with the 170 intake valve and 144 exhaust valve and a .100 mill of the head if its stock CC's. 20 horsepower here i come! lol
 
After the porting is done iam going with the 170 intake valve and 144 exhaust valve and a .100 mill of the head if its stock CC's. 20 horsepower here i come! lol
The porting can't be "done" until after You've established the new pocket with the O/S valves,....and that's the most critical part................
 
Have you tried to get the valves yet?
Actually i guess this head had bigger valves installed prior i got three heads in a bundle and, this one i can tell the valve stem is wider but i measured it and the intake valve is at 1.66? the other intake valve is 1.62 on the other head. does this make any sense? i thought the next size up was 1.70
 
The valve stems are still 3/8" on the larger valves? Not a commonly used O/S valve, not sure what they used, may have done like I did by picking something by size from a valve parts-list by size.
I chose a BBM 1.74" exh for the intake, and an AMC 1.41" exh. for the exh., they were workable for this app.
 
The valve stems are still 3/8" on the larger valves? Not a commonly used O/S valve, not sure what they used, may have done like I did by picking something by size from a valve parts-list by size.
I chose a BBM 1.74" exh for the intake, and an AMC 1.41" exh. for the exh., they were workable for this app.
yeah im not sure i bought this head and other parts off a slant six racer from the 80's. i wish i knew more
 
The valve stems are still 3/8" on the larger valves? Not a commonly used O/S valve, not sure what they used, may have done like I did by picking something by size from a valve parts-list by size.
I chose a BBM 1.74" exh for the intake, and an AMC 1.41" exh. for the exh., they were workable for this app.
KILLER6
these would be a direct drop in of some fiddeling required?
 
KILLER6
these would be a direct drop in of some fiddeling required?
Depending on Your particular chambers and the stem height after establishing the seats, they're pretty good, the exhausts were a bit tall and require trimming the stem tips a little. Spring heights are within range for shimming or cutting their seats.
 
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