ProComp/Speedmaster aluminum heads

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I think that once you go through the head and find it OK for use, you’ll be fine. Excellent advice has been and I’m sure will still be given if the need should arise.
 
I’d def have the springs tested.

The ones I had here, which were a dual spring w/o damper, that used 10* retainers and locks...... listed as for use with flat tappet cams....... had waaaaay less spring load than the specs that were just posted.
 
PRH said:
I’d def have the springs tested.

The ones I had here, which were a dual spring w/o damper, that used 10* retainers and locks...... listed as for use with flat tappet cams....... had waaaaay less spring load than the specs that were just posted.
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Remember a discussion about not being able to use my valves from my cast iron heads, but wondering now if I can just swap my Springs over? I guess I'm not sure if the retainers and such would fit? Or would I just use the spring itself with the same retainer?
 
j par said:
Remember a discussion about not being able to use my valves from my cast iron heads, but wondering now if I can just swap my Springs over? I guess I'm not sure if the retainers and such would fit? Or would I just use the spring itself with the same retainer?
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Not likely. If your SM heads have an installed height of 1.900 and your stock heads may be (as in might be) 1.800 you have too little seat pressure and not enough over the nose. I suspect you probably only have a 1.750 installed height on your heads now, so they are even shorter.
 
PRH said:
I’d def have the springs tested.

The ones I had here, which were a dual spring w/o damper, that used 10* retainers and locks...... listed as for use with flat tappet cams....... had waaaaay less spring load than the specs that were just posted.
Click to expand...


How were the springs that came in the Edelbrock heads. Are they better than what you have seen in the Speedmaster heads.
 
pittsburghracer said:
How were the springs that came in the Edelbrock heads. Are they better than what you have seen in the Speedmaster heads.
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PRH said:
I’d def have the springs tested.

The ones I had here, which were a dual spring w/o damper, that used 10* retainers and locks...... listed as for use with flat tappet cams....... had waaaaay less spring load than the specs that were just posted.
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Also can you put a ballpark number to "waaaay" ? Also it seems like if you shimmed two of them those must have been way-way out? LOL...
 
20170520_185041.jpg

I remember on this 318 for my wife I had some 360 heads from a core motor that I took apart and sent down to a shop and had .060 milled off.. I had the newer 188 intake valves from when I had my 202's put in my current heads. I took some lapping compound and put it on the edge of the valve and the seat and put a little piece of rubber hose over the backside with my drill and pushed a drill bit in the other side of the hose. I slowly buzzed it back and forth until the grinding sound went away which only took about 10 or 15 seconds... Cleaned everything up real well put new seals and lubricated everything real well with whatever green goo assembly Lube that I had and put everything back together and they seem to work great..
 
Ede SBM RPM head springs, the ones that come on the heads for flat tappet cams, test at [email protected], [email protected], [email protected]...... which is pretty much right on with what the specs are.
For solid cam use, it would have to be a pretty mild set of lobes for me to not swap the springs.
I usually shim them up to 130 on the seat for most applications where I feel the spring is adequate.

I don’t recall the open pressures exactly on the SM heads........ but I remember thinking it was barely adequate for the XE268 cam that was going to be used with those heads.
Something like 250-275 open.
They were in the 115-120lb on the seat range.
The spring had a pretty low rate, but lots of travel, so plenty of room to shim them up.

For solid cams with that type of head I use a Crane 99893, or one of the equivalents offered by some other companies.
 
PRH said:
Ede SBM RPM head springs, the ones that come on the heads for flat tappet cams, test at [email protected], [email protected], [email protected]...... which is pretty much right on with what the specs are.
For solid cam use, it would have to be a pretty mild set of lobes for me to not swap the springs.
I usually shim them up to 130 on the seat for most applications where I feel the spring is adequate.

I don’t recall the open pressures exactly on the SM heads........ but I remember thinking it was barely adequate for the XE268 cam that was going to be used with those heads.
Something like 250-275 open.
They were in the 115-120lb on the seat range.
The spring had a pretty low rate, but lots of travel, so plenty of room to shim them up.

For solid cams with that type of head I use a Crane 99893, or one of the equivalents offered by some other companies.
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I'm pretty sure I have Crower Springs and I remember something about 350...
Thank you I'll look those up...
 
I feel the writing on the wall that I'll need another set of Smith Brothers pushrods...
 
I’m betting I have some new stock Edelbrock springs because I always take them off and upgrade my springs
 
I'm pretty sure I have Crower Springs and I remember something about 350...
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I don’t think you’ve grasped the idea that “most” springs designed for use with OE SBM heads are going to be too short to properly fit the new heads.

Forget what the catalogs and “specs” say.
The springs are what they are......regardless of the what the specs say they are.

Have both sets of springs tested at the installed height of the new heads.
The old springs are either suitable for that height, or not.
 
PRH said:
I don’t think you’ve grasped the idea that “most” springs designed for use with OE SBM heads are going to be too short to properly fit the new heads.

Forget what the catalogs and “specs” say.
The springs are what they are......regardless of the what the specs say they are.

Have both sets of springs tested at the installed height of the new heads.
The old springs are either suitable for that height, or not.
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Thank you I think I'm starting to get a grasp of what you're saying. I went out and made a very crude measurement of my installed height on my sm heads..
I'm starting to think my first tool will be a spring height measuring tool..
 
j par said:
Thank you I think I'm starting to get a grasp of what you're saying. I went out and made a very crude measurement of my installed height on my sm heads..
I'm starting to think my first tool will be a spring height measuring tool..
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What was your close measurement? It's really hard to get much more that 1.725ish with stock length valves. I don't think I'm even at 1.700. That's one of the issues with OE heads. Then you add long valves and the geometry goes even more off the rails, and to correct it used to be a real mother bear.

That's why I never ran a roller cam on OE heads. You can't get the installed height to get the lift in there.
 
yellow rose said:
What was your close measurement? It's really hard to get much more that 1.725ish with stock length valves. I don't think I'm even at 1.700. That's one of the issues with OE heads. Then you add long valves and the geometry goes even more off the rails, and to correct it used to be a real mother bear.

That's why I never ran a roller cam on OE heads. You can't get the installed height to get the lift in there.
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1.86
 
IMG_20191009_185438.jpg

Good gravy it must have took me 20 minutes to get this damn picture downloaded! I must have tried 40 different ways... I got my thinnest feeler gauge and bottom dip out next to the valve spring and made a careful look at exactly we're on the little black mark the retainer started...
 
Jpar my advice would be to send the heads to a competent shop and let them go over the heads and install the correct springs for your cam.
 
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