My home inspection of Speedmaster heads

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This is all I'm doing. I used a buffer on a Dremel and removed the burr where the seat was pressed in and smoothed it out with a buffer. That's it. We'll see how these stack up against stock head on a stock 360. Should be interesting when the time comes.... Pictures of one done and the other not. Don't show the burr well on the exhaust side, but the sharp edge is gone.

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PRH
 
and one head back together... About 3+ hrs to take one apart (and mark), smooth out the burrs, clean thoroughly, and reassemble. The exhaust valve marked "D" is about .008-.010 higher (at valve stem) than the rest (the rest are equal) with a flat edge.

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Have you tried gaskets to see how close the ports are? I have a bunch of 273/318 gaskets but will need to get some 340/360 gaskets to compare.
yes, I believe I showed that in the video in the first post. I was impressed with the casting of these...
 
yes, I believe I showed that in the video in the first post. I was impressed with the casting of these...


Honestly I am too. Especially if you know a small block Edelbrock Head maxes out at 243 cfm. If they would learn how to do a valve job they would even sell more of them.
 
Speaking of port openings...... the cnc head port openings are bigger than the gaskets I have here.

2.350H x 1.200W for the head

2.250H x 1.160W for the gasket(Fel Pro blue)
 
I was out of town for Christmas and missed many pages of information here. I had better get busy! Thanks guys for all the great information.
 
Honestly I am too. Especially if you know a small block Edelbrock Head maxes out at 243 cfm. If they would learn how to do a valve job they would even sell more of them.

hope you guys that paid for heads are giving that feedback to SM. That’s the only way they will change. It’s possible that the management doesn’t even know how bad the valve jobs are.
 
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hope you guys that paid for heads are giving that feedback to SM. That’s the only way they will change. It’s possible that the management doesn’t even know how bad the valve jobs are.
I don't think SM is going to do the work that some of these guys are doing on their heads. They are at the bottom of the barrel in pricing. I found their heads to have great casting and serviceable hardware. Really, to get these heads to a place like PBR is taking them, you'd pay a machine shop a grand at least. If you can't do it yourself, better off just buying TF.
 
I don't think SM is going to do the work that some of these guys are doing on their heads. They are at the bottom of the barrel in pricing. I found their heads to have great casting and serviceable hardware. Really, to get these heads to a place like PBR is taking them, you'd pay a machine shop a grand at least. If you can't do it yourself, better off just buying TF.
I would agree they are cheap when on sale but otherwise I don't think they are cheap enough given the valve job and hardware. Now I will also say I think the edelbrocks are overpriced for what they are, if we look at the chevy/ford offerings they are more in line with what prices should be.

I know they sale more of those heads but they also have more choices compared to mopar so I would bet they do just fine on how many units sold a year and could sale even more with reduced pricing. I am hoping (knowing it's pie in the sky) that the trickflow will force the issue considering the early results on sales.
 
I don't think SM is going to do the work that some of these guys are doing on their heads. They are at the bottom of the barrel in pricing. I found their heads to have great casting and serviceable hardware. Really, to get these heads to a place like PBR is taking them, you'd pay a machine shop a grand at least. If you can't do it yourself, better off just buying TF.

I don't disagree with you at all. I was more addressing what PBR and others had mentioned about the valve job and even the CNC work at the port entrance and under the valve seat. Even at the lower end of the spectrum, they can tweak requirements here and there to make improvements in the final product, that won't cost them in the manufacturing process. I do it all the time with the stuff my company makes. Not everything is doable, but there obviously is some low hanging fruit here. SM won't change unless they hear from their customers. I know my business won't spend a dime on process unless there are more dimes to be saved ( and I can demonstrate that), or a customer is not happy.
 
On the set I had the thread ends sure we’re sharp edged. Needs some attention with at least a sanding roll, add a nice radius down into the hole where the plug end sits

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and one head back together... About 3+ hrs to take one apart (and mark), smooth out the burrs, clean thoroughly, and reassemble. The exhaust valve marked "D" is about .008-.010 higher (at valve stem) than the rest (the rest are equal) with a flat edge.

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Did you figure out the valve length issue? If it's the seat causing the problem could you machine some off the stem to correct it or is .010 nothing to be concerned about?
 
I would probably have at least 10 questions to ask these guys but no one's wanting to let go any secrets.. it's just the same four or five guys that have flow benches talk in their language to each other... That's why I called it chest beating because really everybody wants to just talk as if they know so much that this isn't worth their time to talk to anybody who doesn't...
 
It would be nice to take a bare head port and again I've said it on the other thread color coded as it goes down like green as in take a lot here yellow be cautious here and red don't take away too much here..
 
PBR or the other experienced porters, what do you think of the spark plug threads exposed in the chamber? On the set I had the thread ends sure we’re sharp edged as cut. On the TF’s they are rolled over smooth. No big deal and just a cosmetic detail or?

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So I wonder if the reach of the plug or the threads of the plug would cover those endings up and then really be exposing the plug?..
 
It would be nice to take a bare head port and again I've said it on the other thread color coded as it goes down like green as in take a lot here yellow be cautious here and red don't take away too much here..
I threaded in an Autolite 3924 and no the strap just barely protruded. Those thread ends are exposed. Me, I’d have hit them with a sanding roll and reduced the sharp edges for obvious reasons. Additional Cc’s be damned. Don’t want sharp edges in the chamber now do we.
 
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I threaded in an Autolite 3924 and no the strap just barely protruded. Those thread ends are exposed. Me, I’d have hit them with a sanding roll and reduced the sharp edges for obvious reasons. Additional Cc’s be damned, maybe others can opine as to whether it is of no concern, or otherwise.
yes I just checked my spark plugs and I used to run those Autolite 3924 so as well.. I tried one heat range hotter this year and used in NGK V Power 8..
Thank you for that tip all address that as needed.. also I'm wondering if this is more of a concern with cast iron than aluminum?..
I grabbed the two different plugs and took a picture real quick while I was out checking what I am running I forgot it's been a few months now.. and for some reason I can't find the book that I write them down in.. also I pulled the cover and looked inside my car and gave myself a shock as I forgot my seats are at the reupholstery shop...
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the next Heat range up is still pretty cold and insulator is still inside.. just not down in the hole..
 
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