Will check exactly what's going on when I get a stronger spring compressor, if you look at the picture of just the two springs, there's just a short bit of the flat protruding. from the retainer, slightly out of round, I may be assuming too much, hard to tell with a straight edge along the springs.
My home inspection of Speedmaster heads
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yellow rose
Overnight Sensation
I think 12many was talking about the spring/retainer fit.
When these threads get this long I often get way out in the weeds!!
yellow rose
Overnight Sensation
^^^^^^^^^TREE'D^^^^^^^^
LOL I'm way slow these days
LOL I'm way slow these days
Shop I called isn't interested in flowing a head they're not doing work on. PRH is in VT and would require shipping. If anyone in New England knows a shop in CT or Western Mass that would be willing to flow one head, send me a PM.
PRH
Well-Known Member
PRH
Well-Known Member
I wouldn’t charge you to flow it, but the freight would be on you.
If that's the case, 40 bucks round trip is a bargain considering Dwayne will flow it at no charge.
Plus the added factor is Dwayne will have his eyes on the head, he will see even if he don't want to.
PRH
Well-Known Member
The ID of the seat ring is basically the same size as the plunge cut in the bowl.
Where the plunge cut ends there is a raised lip, but it doesn’t hang in too much.
A few mins with a carbide and it’ll be gone.
I love the comments in various threads about the “20 year old” valve job.
Well, I’ve been doing it for 30 years...... and never did them like that.
I’d say more like a 100 year old valve job.
When discussing it with some of the shops I do work for, we refer to it as the “full width” valve job........ meaning it’s as wide as the valve face.
Although that’s not really accurate with many valves......as the valves are often nowhere near that wide.
The seat width on these heads is about .120-.130 wide....... so, over twice as wide as they’ll be after I recut them.
PRH
Well-Known Member
cookietruck
Well-Known Member
you got a deal on the heads, have him do a performance a valve job on your heads and see where that gets you...
PRH
Well-Known Member
Well, the head in my pic is a BBM 210cc head, I’ve done 1/2 dozen or so sets of those, I’ve done two sets of the BBM 265cc/325cc “Victor copy” heads......only one set of the SBM heads...... probably a dozen or so sets of BBC heads(I’m referring to Pro Comp/SM heads).
For the “budget” SBC guys I use a head that comes from a different supplier.
I’ve had about a dozen or so sets of those through the shop as well.
The aftermarket head I’ve had in the shop most often are actually the Ede RPM/E Street BBM heads.
I’ve done well over a hundred sets of those through the years.
I typically get more BB work than SB, but I’ve probably done around 40 sets of Ede RPM SBM heads as well.
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gzig5
Well-Known Member
Once I get the heads apart (after Christmas) they'll be going up to Dwayne, he's going to flow them as is, and then do a valve job on them and flow again. So we should have some extra data after the new year at some point.
PRH
Well-Known Member
My SOP for this set will be to recut the intake seats with at least 4 angles..... they may get another angle added to the top..... I’ll just have to see what it looks like after the initial cut.
Exhaust will be 2 angles and a radius.
After the seats are cut, then I’ll blend the bowls up to the new seat work.
Exhaust will be 2 angles and a radius.
After the seats are cut, then I’ll blend the bowls up to the new seat work.
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lead69
hopeless car junkie
That's the ticket. Before and after comparison. Should have had mine done that way but I didn't.
PRH
Well-Known Member
Might still be the current thinking for some HD or Diesel stuff.
I don’t like doing that type of head work.......so I don’t.
I just picked my BB heads up today, and gave them a quick go-over. Whew! The intake valves are H-U-G-E, they almost look like coffee saucers! All the machined surfaces are flat, and the saddles for the rocker arms look true. There were no chips or metal flakes to be found in the ports or threaded holes. All the threads look good. Some initial photos, with more to come as I get into these things.
The inside of the ports could use a little massaging to radius some edges, but really the machining looks pretty good on the ports. Here's a typical spot where there's an edge you can feel easily, that even Dummy Me can smooth out with the die grinder.
The only thing that looks odd, and I will have to get some advice from those that know better, is the height of the valve stems is not the same. All the intakes are the same, and all the exhausts are the same, but the exhaust valves sit about .040" lower than the intakes. Here's a shot with a straight-edge resting on top of the intake valves, and here you can see the gap at the exhaust valve. More updates on these as I get into them in the next few days.
The inside of the ports could use a little massaging to radius some edges, but really the machining looks pretty good on the ports. Here's a typical spot where there's an edge you can feel easily, that even Dummy Me can smooth out with the die grinder.
The only thing that looks odd, and I will have to get some advice from those that know better, is the height of the valve stems is not the same. All the intakes are the same, and all the exhausts are the same, but the exhaust valves sit about .040" lower than the intakes. Here's a shot with a straight-edge resting on top of the intake valves, and here you can see the gap at the exhaust valve. More updates on these as I get into them in the next few days.
LOL... I made a remark on the size of the intake valves in another thread
PRH
Well-Known Member
Pro Comp or SM boxes?
Dates on the heads?
Dates on the heads?
All the valves had slightly different shimming under each spring, between .053 and .073.
Seals were all tight to the guides (getting replaced anyways)
Some casting flash left in 3 out of four exhaust ports on the same side (Best/worst ports pictures)
Intakes were even better, only one small spot where the head bolt goes, and only on one port.
Core shift, based on the porting work, seems to be very minimal.
Seals were all tight to the guides (getting replaced anyways)
Some casting flash left in 3 out of four exhaust ports on the same side (Best/worst ports pictures)
Intakes were even better, only one small spot where the head bolt goes, and only on one port.
Core shift, based on the porting work, seems to be very minimal.
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