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-   -   '67 Camaro E/SA redo (https://classracer.com/classforum/showthread.php?t=50660)

HandOverFist 03-03-2014 04:18 PM

Re: '67 Camaro E/SA redo
 
Quote:

Originally Posted by Dave Turner (Post 422853)
I think quadrajetparts.com has a 2 piece solution for you. A 1" extension plus an inverted flare to -8 adapter.

Dave - This is all I come up with in the search box... http://quadrajetparts.com/rochester-...ing-p-367.html

Bill Harris 03-03-2014 05:05 PM

Re: '67 Camaro E/SA redo
 
Those reinforced perches will probably survive the next world war. However, it might be good to reflect on what happened and try to identify the root cause of the original failure. It is easy to say that the Moser perches are defective/weak/junk/chinese, etc. and that they should know better since they build axles for drag racing and have for many years. But before crucifying them, the posted pictures show that this might well have been a case of mixing incompatible suspension components.

Looking at the end view of the collapsed perch it is apparent that the wedge used to set the pinion angle is too narrow for the perch. The implementation created a pyramidal structure with the spring at the base, a narrower spacer and an even narrower wedge working against an unsupported surface. The compressive force generated by the housing rotation was applied through the unsupported horizontal portion of the perch to the narrow wedge. That force on the horizontal part was more than it could support and it collapsed.

The horizontal portion isn't supposed to take the load, the vertical portions of the perch should be taking the load and transferring it (ultimately) to the spring. The vertical portions of the perch were essentially unsupported in this application as witnessed by their being forced apart and actually torn away from the horizontal part of the perch on one side. The modified perches, as well as the Calvert perches provide additional support to the horizontal portion of the perch, certainly a much more robust design.

As witnessed by many racers, even stock 40 year old perches can withstand the forces generated by drag race launches, although it certainly isn't a good idea. I suspect that if the springs were in direct contact with these perches they would never have failed. That wedge, in that position, was the ultimate culprit. Putting the wedge between the spring and the slightly wider solid spacers might have provided enough support to prevent the failure too, but since the spacers look to be narrower than the perch it would be marginal.

Also, Calvert can supply their springs with different amounts of arc so that the ride height can be set without having to have a bunch of spacers between the perch and spring. He also has wedges which are wider than the usual 2" parts.

Alan Nyhus 03-03-2014 05:49 PM

Re: '67 Camaro E/SA redo
 
Rich, I can't emphasize enough how important it is to fabricate locating pins that fully engage the holes in the perches. -Al

FED 387 03-03-2014 06:23 PM

Re: '67 Camaro E/SA redo
 
u looking for a 7/8-20 one inch long or a 5/8-20 one inch long??? can u use a 2-3 inch long fitting for a -8 hose???

Rich Biebel 03-03-2014 07:59 PM

Re: '67 Camaro E/SA redo
 
Quote:

Originally Posted by Bill Harris (Post 422860)
Those reinforced perches will probably survive the next world war. However, it might be good to reflect on what happened and try to identify the root cause of the original failure. It is easy to say that the Moser perches are defective/weak/junk/chinese, etc. and that they should know better since they build axles for drag racing and have for many years. But before crucifying them, the posted pictures show that this might well have been a case of mixing incompatible suspension components.

Looking at the end view of the collapsed perch it is apparent that the wedge used to set the pinion angle is too narrow for the perch. The implementation created a pyramidal structure with the spring at the base, a narrower spacer and an even narrower wedge working against an unsupported surface. The compressive force generated by the housing rotation was applied through the unsupported horizontal portion of the perch to the narrow wedge. That force on the horizontal part was more than it could support and it collapsed.

The horizontal portion isn't supposed to take the load, the vertical portions of the perch should be taking the load and transferring it (ultimately) to the spring. The vertical portions of the perch were essentially unsupported in this application as witnessed by their being forced apart and actually torn away from the horizontal part of the perch on one side. The modified perches, as well as the Calvert perches provide additional support to the horizontal portion of the perch, certainly a much more robust design.

As witnessed by many racers, even stock 40 year old perches can withstand the forces generated by drag race launches, although it certainly isn't a good idea. I suspect that if the springs were in direct contact with these perches they would never have failed. That wedge, in that position, was the ultimate culprit. Putting the wedge between the spring and the slightly wider solid spacers might have provided enough support to prevent the failure too, but since the spacers look to be narrower than the perch it would be marginal.

Also, Calvert can supply their springs with different amounts of arc so that the ride height can be set without having to have a bunch of spacers between the perch and spring. He also has wedges which are wider than the usual 2" parts.

Bill that is a nice failure analysis.....I saw the spacers and wedge plate but could not see it close enough to see what you are pointing to. Makes total sense to me.....

HandOverFist 03-03-2014 08:08 PM

Re: '67 Camaro E/SA redo
 
Quote:

Originally Posted by Bill Harris (Post 422860)
Those reinforced perches will probably survive the next world war. However, it might be good to reflect on what happened and try to identify the root cause of the original failure. It is easy to say that the Moser perches are defective/weak/junk/chinese, etc. and that they should know better since they build axles for drag racing and have for many years. But before crucifying them, the posted pictures show that this might well have been a case of mixing incompatible suspension components.

Looking at the end view of the collapsed perch it is apparent that the wedge used to set the pinion angle is too narrow for the perch. The implementation created a pyramidal structure with the spring at the base, a narrower spacer and an even narrower wedge working against an unsupported surface. The compressive force generated by the housing rotation was applied through the unsupported horizontal portion of the perch to the narrow wedge. That force on the horizontal part was more than it could support and it collapsed.

The horizontal portion isn't supposed to take the load, the vertical portions of the perch should be taking the load and transferring it (ultimately) to the spring. The vertical portions of the perch were essentially unsupported in this application as witnessed by their being forced apart and actually torn away from the horizontal part of the perch on one side. The modified perches, as well as the Calvert perches provide additional support to the horizontal portion of the perch, certainly a much more robust design.

As witnessed by many racers, even stock 40 year old perches can withstand the forces generated by drag race launches, although it certainly isn't a good idea. I suspect that if the springs were in direct contact with these perches they would never have failed. That wedge, in that position, was the ultimate culprit. Putting the wedge between the spring and the slightly wider solid spacers might have provided enough support to prevent the failure too, but since the spacers look to be narrower than the perch it would be marginal.

Also, Calvert can supply their springs with different amounts of arc so that the ride height can be set without having to have a bunch of spacers between the perch and spring. He also has wedges which are wider than the usual 2" parts.

Bill - Looking at it again I believe you are correct on the narrow wedge...I will replace that with some full width Calvert shims. Good to have extra eyes on stuff like this. The perch may or may not have failed otherwise even without being boxed in.

There is one other thing that has been on my mind during this ordeal. I had no inclination to undertake this repair on my own Sunday...my only goal that morning was to gut/remove the housing from the car so we could get it sent off for repair. When my partner showed up he was hell bent on fixing it himself. I questioned him how he was going to do it and he assured me he had it in hand. I'm no blacksmith or welder so I deferred to his judgement. I have always heard about being careful when welding/heating axle tubes, but my concerns were played down. I must say that a ton of heat went into those perches and a bunch more into the tubes during extended welding. Perry confided to me earlier to make sure my partner welded a little at a time and swap sides to allow some cooling. I mentioned it to my partner, but it went unheeded. Should I be concerned about this?

HandOverFist 03-03-2014 08:10 PM

Re: '67 Camaro E/SA redo
 
Quote:

Originally Posted by Alan Nyhus (Post 422864)
Rich, I can't emphasize enough how important it is to fabricate locating pins that fully engage the holes in the perches. -Al

Pins are good Alan...thanks! :)

HandOverFist 03-03-2014 08:15 PM

Re: '67 Camaro E/SA redo
 
Quote:

Originally Posted by FED 387 (Post 422867)
u looking for a 7/8-20 one inch long or a 5/8-20 one inch long??? can u use a 2-3 inch long fitting for a -8 hose???

It's a 1901 Edelbrock and I'm pretty sure it's a 1-20 thread fitting...larger than my Rochester quadrajets. I just need one that is extended length like the one I posted earlier so my line from the regulator will reach as it does for my other carbs.

Dave Turner 03-03-2014 08:45 PM

Re: '67 Camaro E/SA redo
 
Quote:

Originally Posted by HandOverFist (Post 422857)
Dave - This is all I come up with in the search box... http://quadrajetparts.com/rochester-...ing-p-367.html

This is the link to the extension fitting:
http://quadrajetparts.com/rochester-...ing-p-436.html

Then you need this adapter - (available from other sources.)
http://quadrajetparts.com/rochester-...ing-p-370.html

I assumed that you were working with a Quadrajet carb. The search continues. :o

Rich Biebel 03-03-2014 09:18 PM

Re: '67 Camaro E/SA redo
 
I doubt you did warp the tubes from welding as it takes a lot of welding around the tube to do that....You may have tweaked them a bit but if the axle bearings went right in with no issues I think you will be fine....


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