My home inspection of Speedmaster heads

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toolmanmike said:
I would think FP Print-o-seal's would be good. But I don't know for sure.
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I've always just ran the "over the counter" felpro's. Never had an issue. I thought the SM's for 7 bucks on 40% off was a good deal. But it was 7 dollars too much!!!! LOL
 
318willrun said:
I've always just ran the "over the counter" felpro's. Never had an issue. I thought the SM's for 7 bucks on 40% off was a good deal. But it was 7 dollars too much!!!! LOL
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I have steel shims on my 273 but both surfaces are cast and both have been machined.
 
Looks like DIY stick downs to me.
Most will break when they land dead nuts on the end, more like crease and become a hinge flopping back and forth till it falls off.
Drop a 1213.

Blue ones dont have that issue
 
Just got done assembly my sm heads after porting and valve job with backcut valves. Set the shafts in the saddles to check some geometry. Not a good fit at all. Seems they were machined for a .950 shaft. So now I have to make some special shims to make them work. I missed it. Live and learn.
 
aaronk785 said:
Just got done assembly my sm heads after porting and valve job with backcut valves. Set the shafts in the saddles to check some geometry. Not a good fit at all. Seems they were machined for a .950 shaft. So now I have to make some special shims to make them work. I missed it. Live and learn.
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How close is the geometry? If it needs to be corrected you can get ahold of Mike at B3 and tell him what you have and maybe he can make you shims to correct the big saddles.

I must say, I've never heard of any shafts that big so I'm stumped.
 
I'm no geometry expert but it seems pretty close. Using 273 adj. rockers they sweep from one side to the other and close to center at mid lift. Sweep is close to centered on the valve. Is this right? Sweep is almost the full width of the valve.
 
aaronk785 said:
I'm no geometry expert but it seems pretty close. Using 273 adj. rockers they sweep from one side to the other and close to center at mid lift. Sweep is close to centered on the valve. Is this right? Sweep is almost the full width of the valve.
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The sweep should be centered and about .030" wide .
Sweep of full width of the valve is not good.
You really want it centered and to reverse direction throughout the lift cycle.
 
I knew that was the case with a roller rocker. I thought a iron rocker was different. I must be way off.
 
Every stock or iron rocker I've seen had wear mark atleast the width of the valve. Looks like the rocker actually rolls over the valve and don't scrub much.
 
aaronk785 said:
Every stock or iron rocker I've seen had wear mark atleast the width of the valve. Looks like the rocker actually rolls over the valve and don't scrub much.
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Probably so because the oem rockers have a pad instead of a roller.
 
Installed a .040 non tapered shim. Made the shaft fit the saddle perfect and helped geometry some also. .870 + .080 = .950.
 
I was sitting here feeling pleased with myself for finding a piston that gave me what I wanted for DCR and allowed me to run a thin enough gasket to get good quench clearance, and I realized that I had done all my math on the supposed 68cc chamber sized.

Unfortunately, I'd feel better if SM didn't give two different chamber sizes, 65 and 68cc, depending on if you got CNC porting or not, but they only do chamber work on the bare cnc heads, the assembled ones have as cast. Worse, the edelbrocks they're based on are supposed to be 63cc.

Here's the question...Has anyone CC'd the chambers on any of the SM heads?
 
pittsburghracer said:
I haven’t.
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Well get cracking...
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pittsburghracer said:
Ohhh damn I’ll add another job to the list. I’m taking it you need a stock non cnc’d Speedmaster Head chamber cc.
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I don't have access to a good setup at work anymore, so I'm in the process of piecing one together right now. I know SM claims a difference in the two, as cast vs CNC, but the CNC work is ports only on my heads, so they should really be the same.

If you succumb to the arm twisting before I get a chance, great, if not I plan to post up numbers as soon as I can.
 
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