427 SBF

You have a picture of two locks with the same installed height and one that is .050 different.

Now, that doesn't mean you can't mix and match stuff. You MUST use the same degree locks to go with the retainer, NO CHOICE in that one! Use the wrong stuff, you will be HATING life!

You can buy locks at STD, -0.050 and +0.050. Now for some STUPID reason some retainers are made to be taller or shorter than normal...... I ran into this with my wives AFR's I am rebuilding. Stupid retainers are +0.050. So just when I thought I had all my stuff ready to assemble when I get the heads back from the machine shop I will be determining installed height all over again and most likely putting .050 shims under the spring seats. No problem, obviously it is all apart.

But, if you already put the seals on the guides, then they have to some off to put shims under your spring seats. It's no big deal. I can loan you my installed height mike if you want it, but you can also get a good measurement with your caliper. I have checked with both, they are the same if you can measure stuff. The mike makes it much easier, that's all.

If you are going from +.050 locks to STD, then your installed pressure will be higher, and I think that's the way you are headed. So you certainly won't be putting any more shims under your seats unless you want even MORE pressure. A hydraulic roller should be at least 150lbs on the seat, I run up to 175lbs. Open pressure depends on the lifter manufacturer. I go through the PAC catalog to find a spring that has the pressure I want at the installed height I can easily do, and then see what they are at my full lift. I had to get +.100 longer valves for these heads to get the pressures where I want them.
 
I understand the frustration, but today is a new day, and new outlook. Dyno won’t be running for a few more weeks, so you have time. The experience will just be more tools for your toolbox. Literally and figuratively. 🙂
 
CompNut said:
Just buy the damn AFR heads and be done with it, we all know that's what you really want.
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Be done with it?

I don't think you understand how much those afr heads will fuck me. At the very least I'll be another $1000 into headers alone to try and fit around all the shit in a foxbody.

More than likely the midpipe would have to be scrapped, the motor mounts would need to be custom made, causing the pinion angle to change depending on how tight to the body the headers are I might have to angle the engine

then a switch to a Hydraulic clutch with different fork would be needed.

Now we're $5k to $7k into a "different heads and be done with it"
 
See post #1496

Promaxx uses "classic keepers" (Michigan motorsports). The bead location is moved +.030 inches to eliminate the need for spring shims (supposedly)

They are hardened (heat treated)

They do not have other locks available unless I switch to the titanium retainers (which are 10 degree). This would require spring shims to get installed height correct.

@CompNut the retainers won't solve it. Best case scenario I would then need to disassemble, get shims, new seals, and with my luck, new valves would be required, which would then likely require heads to go to a machine shop to get the valves to seat properly. This cascade effect is relentless.

I'm not having fun anymore
 
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89 Fox 427 said:
See post #1496

Promaxx uses "classic keepers" (Michigan motorsports). The bead location is moved +.030 inches to eliminate the need for spring shims (supposedly)

They are hardened (heat treated)

They do not have other locks available unless I switch to the titanium retainers (which are 10 degree). This would require spring shims to get installed height correct.

@CompNut the retainers won't solve it. Best case scenario I would then need to disassemble, get shims, new seals, and with my luck, new valves would be required, which would then likely require heads to go to a machine shop to get the valves to seat properly. This cascade effect is relentless.

I'm not having fun anymore
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Don't sweat it!

Are your retainers 7*, most likely yes? Get standard locks. Looks like they will be -0.030 compared to the locks that came with it. Measuring will tell you. That will give you more spring pressure, might be a good thing.

Seals don't cost much and if you are careful you can re-use them. But for $25 just get a new set. Don't install them until you measure everything. Put the locks and retainer on and see what the installed height is. Like I said earlier, your caliper will give you a pretty good measurement. See what the spring pressure is at that height then decide if you need more shims under the spring seats or not.

This isn't hard to do, I have taught my wife, she will be assembling her heads once I get them back.
 
Mike Beck said:
Don't sweat it!

Are your retainers 7*, most likely yes? Get standard locks. Looks like they will be -0.030 compared to the locks that came with it. Measuring will tell you. That will give you more spring pressure, might be a good thing.

Seals don't cost much and if you are careful you can re-use them. But for $25 just get a new set. Don't install them until you measure everything. Put the locks and retainer on and see what the installed height is. Like I said earlier, your caliper will give you a pretty good measurement. See what the spring pressure is at that height then decide if you need more shims under the spring seats or not.

This isn't hard to do, I have taught my wife, she will be assembling her heads once I get them back.
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Its the opposite. The comp machined locks give me less spring pressure. Down near 125lbs
 
CompNut said:
Shim the springs up at least .030. Easiest and cheapest solution.
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No

You are missing the part where the comp locks hang out of the bottom of the retainer.

That is not the solution
 
89 Fox 427 said:
@Mark O'Neal any advice, have your guys seen any of this or is it just my shit show
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I haven't been following but, from the general gist of the thing, if you change heads you'll just have to start over. We have to fix AFR heads too.

At this point, I have no idea what you're doing.
 
Mark O'Neal said:
At this point, I have no idea what you're doing.
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I'll keep it simple

If you use promaxx heads, do you change to machined locks, or leave the stamped ones in?

Have your customers had any issues dropping valves with promaxx heads
 
CompNut said:
What does that hurt as long as there is plenty of clearance to the valve guide/seal?
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Feels like if you're cobbling this together with mismatched parts it could be an issue. Sort of explained here at 26m35s:

 
89 Fox 427 said:
Its the opposite. The comp machined locks give me less spring pressure. Down near 125lbs
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That is what I figured if the original locks are -0.030 and you are trying standard locks. So either shim the springs .030 to get them back to where they were, or get -0.050 locks and see what the installed height gives you with spring pressure, bet it will be fine.
 
Ask whoever supplied the cam and lifters and see what seat pressure and open pressure they expect.

I would be running 150 pounds on the seat at a minimum, I bet 175 would be fine.

Open, I don't remember off the top of my head, maybe 400ish........

I don't subscribe to the .060 away from coil bind theory either. I have put 1000+ passes on my SBC going to 8000 rpm every pass and they are about .120 and .150 from coil bind. Either I got lucky with springs/rates/weight or that .060 is just a theory...........
 
Mike Beck said:
Ask whoever supplied the cam and lifters and see what seat pressure and open pressure they expect.

I would be running 150 pounds on the seat at a minimum, I bet 175 would be fine.

Open, I don't remember off the top of my head, maybe 400ish........

I don't subscribe to the .060 away from coil bind theory either. I have put 1000+ passes on my SBC going to 8000 rpm every pass and they are about .120 and .150 from coil bind. Either I got lucky with springs/rates/weight or that .060 is just a theory...........
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Mark wanted 155 on the seat and just over 400 open. I'm at 155/401 with the locks they came with
 
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