As Opentracker said in an above post, I built my first set of roller spring perches in 1986 in high school machine shop class. I sold a few sets to most of my buddies in my Mustang club and local circle track racers. I would take several sets to the Pate Swap Meet in Weatherford, Texas every year and sell them all. Back then, if you had a bad spring perch, you either had to find a good used one, an N.O.S. one or pay alot for a new aftermarket perch such as MOOG.
Because of my close proximity to the Mexican border town of Juarez, Mexico, my first big customers were Juarez taxi cab companies that used Ford Granadas, Mercury Monarchs and four door Mavericks and Comets up until about 10 years ago. Mexican roads are not the best, and the taxis were used hard every day. Since those taxis used the same spring perches as the older Fords, they were constantly wearing out the rubber bushed perches. At first, I would convert the taxi cab perches on an exchange basis, but since Juarez was a large manufacturing center, I was able to get a company to build me the perch body and the perch shaft, and all I had to do was install my sleeve and the bearings. Alot of my perches had hundreds of thousands of miles on them by the time the taxis were retired. When the older Fords were replaced with newer vehicles about 10 years ago, my biggest customers dried up.

This was before Ebay had hit it big so I was back to building the perches whenever I could find original Ford perches to rebuild. I finally found a new perch supplier and started selling the perches on Ebay in the fall of 2005 when I began receiving e-mails from people who had seen them on Ebay as part of my spring compressor instructions photo montage. I still build them for taxi cabs in a few South American countries where they still use a version of the older shock tower equipped Fords. I am not a backyard "Johnnie Come Lately", I own and operate a full fabrication shop full time where I build and sell several products for older Fords and Mustangs.

 

Wow, I noticed an immediate change to my car and a very unexpected but very well appreciated reduction to the steering effort for my manual rack and pinion.

I would say it is a very worth the money modification.

Tim

 

I bought the Opentracker roller perches and couldn't be happier. Before I did so, I ordered repro stock perches. They are a lot cheaper but come positioned at an angle that is nearly impossible to install and seat a spring on. Why they don't assemble them in a position closer to normal is beyond me. I tried installing them and "persuading" them into a more acceptable position with a bar only to crack my UCA where they mount. With rollers, that headache is eliminated. Just one more advantage to add to the list if your wallet is telling you to go the cheap route.

 

Tim help me understand how changing to a roller spring perch could possibly reduce steering effort.

I just don't buy that it is what reduced your steering effort.

Did you change anything else at the same time?

 

Sure it does, just not in the way your thinking of it.
If you take a look again at a stock perch installed you can physically see it binding the shock. If you drop the suspension you will see the coil spring will be bowed towards the fender. Because the perch is not rotating like it should. So it kicks out the bottom of the spring. The only reason it stops is the shock is there. Now it's also trying to bend the shock. That's where your bind is coming from, it's not the perch itself.

 

Sorry, I can't give you any specifics other then 'seat of the pants'.

This was the only part replaced. It was, also, the last piece the stock suspension bushing to be replaced, so maybe the effects were highlighted.

Tim

 

I'm considering roller spring perches and idler arm. I just don't know which one to go with.

My car is manual steering with a quick ratio steering box.

 

Perches definitely. I won't even sell the rubber ones anymore after seeing the last car I worked on. Put the rubber perches on it and 1k miles later it was back because it kept loosing the alignment. Cracked the upper control arm. (and the brand new idler with 1k miles on it was junk already) I know it wasn't cracked when I put it in because I checked everything up front to make sure he didn't need anything else replaced.

 

I would highly recommend the F15 perches.

 

CPR -

So, are you saying that a full rebound the stock perch is trying to bend the shock and that stops the suspension from moving? I would buy that.

I would certainly buy that at full rebound something is going to keep the suspension for rebounding further - the perch, the frame, something. My point is that at ride height, and within some reasonable operating range about that ride height, the stock perch is not keeping the suspension from moving. It certainly does add resistance to movement (as do your coil spring and shock), but it does not keep the suspension from moving.

I will admit that my previous ASSumption regarding the stock perch acting as an additional damper is INCORRECT. I still have a set of relatively new replacement rubber bushings from when I installed the set of F15's that I have now - and I finally got around to experimenting with them as I have intended for some time.

My oringinal assumption that led me to describe the perch as a damper was that the shaft would rotate relatively freely within the rubber bushing after some high amount of torque was applied. The assumption being that the friction between the rubber and the shaft would create a counter-rotational torque whose increase is linear with the speed of rotation. If this were the case, a comparison to a damper would be in order. However, such is not the case.

If you lock the perch in a vise and attempt to rotate the shaft you will note that with about 30 ftlb of torque you are able to rotate the shaft; however, with each additional degree of rotation, the shaft becomes harder and harder to rotate (more torque required) until you can no longer rotate it.

This exactly describes the nature of a torsional spring.

With this knowledge, I would contend that a suspension with the stock perches installed will have a higher wheel spring rate than one with rollers. Whether this is of benefit or not to a given vehicle is dependant on many other factors.

However, IMHO, it adds some sense of irony to the direction that many take with their suspension choices - i.e. add 600 in/lb springs to increase wheel rate, and then add roller perches - effectively reducing wheel rate.

I would re-iterate my original post that F15's spring perches are damn near aircraft grade - I am not deriding them; and I will not take them off my car. But I do think that some level of reality check about their function - and benefit to a classic Mustang - is deserved - especially compared with their price.

They aren't Chuck Norris' tears.