427 SBF

The locks also slightly stick out from under the retainers.

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This is such a shit show. I should just get the stamped locks from promaxx and stick the fuckin things back in there.
 
WillisonTfosdik said:
FWIW, that will most likely change the installed height of the spring which will change spring pressure & distance to bind.

I can’t tell from the pic but are there spring locators under the springs or do the springs sit right on the head?
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I was wondering where you have been. I was going to start a thread. Glad you’re back.
 
89 Fox 427 said:
It's not right on the head. Not shims, but like a top hat. I have crap measuring equipment, so roughly here...

It changes the installed height from 1.79 to 1.84. I don't know if shims or the offset .050 locks are the answer here.
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A shim would be fine, or you might be able to buy your size locator with a thicker base.
 
Steve439 said:
A shim would be fine, or you might be able to buy your size locator with a thicker base.
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Oh jeez, I'm forgetting your stuff is all assembled.
You'd probably have to replace the seals to add a shim or change the locators.
Maybe .050 locks are better, I've never used them so I've never paid much attention to them.
 
Remind me the point of saving money again? I can't recall how this has saved me anything
 
Actually, looking at your photo I'm not sure how your seals work.
Are they like a cup that fits over the guide which will stop you from removing the locators?
 
I have a new thought!

This is probably one of those mismatches between brands.
The Comp locks are a slightly different diameter and slide down farther in the retainer, letting the retainer move up.

Probably the best thing you could do is buy the Comp tool steel retainers for your springs.
You fix your setup and save grams right where they count most.
Your motor will be happier at 6500 RPM.
 
So three paths
- go over your spring pressures- do the math .04-ish x rate* - closed and open and see if it raises any eyebrows with you or us. You might be fine.
- get Comp -0.050 locks, which actually are going to be -.010 for you
- get shims
- Steve439's idea of switching retainers, too. This last one is less sure to work in one step.
*if you don't have "rate", calculate it from the open and closed points the spring manufacturer gives, to get lb/inch.
 
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Post the OD and step diameters of your retainers.

I think I have two sets of dual spring tool steel retainers laying around.
I'll see if they'll work on your springs.
 
Thanks Steve, but I'm just putting the old locks back in. This was a waste of time and money so far. These heads have not been prone to lock failure, so there was really no need to even go buying new ones. Me fucking up the locks with a hammer is not enough reason to change them. Seems more of a hassle than necessary.

Promaxx was supposed to send me replacement locks, and they never did. I'll call tomorrow and get it sorted out
 
I would not use stamped locks on this in this part of the game. Have the spring checked and see what it does at the new height. Put a shim in there or ,as a last option, different retainers. This is just the way hot rodding is . We all do it, May not admit to it. But we all do it. A dropped valve if a stamped keeper fails will wipe just about the complete engine out instantly. Not worth the risk
 
70 tp said:
I would not use stamped locks on this in this part of the game. Have the spring checked and see what it does at the new height. Put a shim in there or ,as a last option, different retainers. This is just the way hot rodding is . We all do it, May not admit to it. But we all do it. A dropped valve if a stamped keeper fails will wipe just about the complete engine out instantly. Not worth the risk
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Pfffttt.....this ain't his 1th motor!! :nutkik:
 
70 tp said:
I would not use stamped locks on this in this part of the game. Have the spring checked and see what it does at the new height. Put a shim in there or ,as a last option, different retainers. This is just the way hot rodding is . We all do it, May not admit to it. But we all do it. A dropped valve if a stamped keeper fails will wipe just about the complete engine out instantly. Not worth the risk
Click to expand...

Why would any manufacturer use them knowing this?

At 1.84 installed height it puts me at 125lbs on the seat. Mark wanted to see closer to 155lbs. These springs are 145lbs @ 1.80 with the stamped locks
 
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