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Wondering about my rear!!??

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N

nomad

Yoda
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Rear axle that is!

I'm going to upgrade the rear axle on my 65 midget and was wondering if I ought to fit the 1275 6 leaf springs with lowering blocks (Available???). Or should I rebuild a set of the 1098 5 leaf springs. The 1275 springs make the rear too high in my opinion. I'm a little concerned about rear axle wind up under power. Is that ever a problem?

Also wondering about the best panhard bar or watts link set-up for "spirited" street driving.

Kurt.
 
No opinions??? Is there a good source for setting up the half eliptic cars rear axle for competition?

Kurt.
 
I have 7 leaf springs. They made the car too high in back so I put in lowering blocks and now the car sits near perfectly. The ride is like a Cadillac compared to worn out spring riding on the bump stops that I had before.

The springs I have on came from a racer. He had bought some of those offset springs so he can now run wider wheels.

I didn't know the difference between a watts link and a panhard bar until about a month ago. Bob Walker (another racer) showed me the operation of the watts link he is installing in the SCCA racer he is building at present. After seeing that demonstration, I'm convinced that for a 1/2 leaf spring car like you're doing, that watts link would be the way to go. When he's done, the axle will controlled by trailing arms and the watts link. The springs just control the bounci-ness, and will have nothing to do with axle location, at least as I understand it.
 
'65 is a square rear wheel arch car (with less room than the RWA cars).

A panhard rod will limit side-to-side motion of the axle so you are less likely to rub on the inside of your fender (especially if you have larger tires/wheels)

I have seven springs on my racer right now, but not exactly standard deal. I took a pile of old springs from several cars and selected the best ones. Then I re-arched them (to lower the car) by cold-hammering them using a 4 lb sledge hammer. Much trial and error, but it has worked out well.

Later, I made more using This Setup

Many racers say they prefer Spridgets to be a bit softer than stock (to give tires a chance to "bite") and may only run or 6 springs.
I prefer things a bit stiffer and a bit more tail-happy.
(yellow arrows are just pointing to end of panhard rod)

panhard1.jpg


panhard2.jpg
 
Bill, where did you get the lowering blocks?
Nial, I think I could easily do re-arching in my press. I assume your panhard rod is home made since it would interfere with the exhaust on a stock car.
Do you guys know a good source for panhard rod or watts link setup's?
Is the extra leaf from a set of spridget springs and what is the best way to locate them? I've rebuilt several sets of springs by carefully disassembleing them and replacing the worn shims between the leafs with moly filled nylon from McMaster Carr. The stock locaters don't take much abuse.
I have a set of rebuilt 6 leafs ready to fit except for the fact they will raise the rear too much.

Kurt.
 
That's it, I can't read this thread any more.
Those bits at the links you are providing are just way too tempting.
 
Ohhh, neat stuff!!! Think I'm going to use it mainly for fabrication ideas though.
Any one offer or go to the trouble of a Watts linkage??

Kurt.
 
Ahhh, Frontline RTL Watts. Looks expensive, Nial, in your experience is it worth that much more than panhard rod. If cost were not a consideration, I'm sure it would be the way to go.

Kurt.
 
Actually, I made mine based on the pictures on the Frontline and Peter May site. Bought all my steel materials from onlinemetelas.com and rod ends from Summit Racing.

I don't know about the RTL Watts.

Rather than panhard or Watts, I'm thinking of doing a rear axle wishbone for my A35.

You can see the wishbone in the bottom of This Page

Another choice is the Mallock Woblink. You can see it Here.

....or, the Mumford Link.

I won't be doing these, but they're interesting.
 
My lowering blocks are just the standard ones that are offered from Mo$$ or Victoria British. I think 1 1/4". .. Most importantly they are not just blocks of aluminum, but have an indent on one side and a tang on the other so that they located properly. Also included in the "kit" were the long "U"-bolts needed.
 
Nial, that wishbone looks pretty effective and really simple.
 
Bayless said:
Nial, that wishbone looks pretty effective and really simple.
Click to expand...

I agree, who makes those? Custom built only or what?
Looks simple enough for someone with a little talent and some great tools.
 
Interesting stuff Nial.
The wishbone is the simplest but I think the attachment to the axle should be more towards the center of the axle. It would appear to me that if there was much suspention movement and the car were to heal over much it would perhaps make the axle move over as well. The Malock just looks weird and the Mumford is back to a Watts link. I like the Watts the best myself but its probably more than I need for the street. I'm thinking of making a panhard rod as of right now. I'm thinking tie rod ends so that they are easy to lube and keep the dirt out.

Kurt.
 
Re: Wandering about my rear!!??

That's what I had. A wandering rear end. Tire rub.
Better with the panhard. Even w/o the rod they only rubbed
under much duress. That Watts is uber cool but not
needed on my street car. Seems it's not needed on a lot of fast race cars.
:wink:
Nial, cool links! :thumbsup:
 
That wishbone or A-bracket as it was called back then, was how rear axles on early Lotus Sevens were located, and later on the first of the Mark 1 Lotus Cortinas.
A good pedigree!
 
Kurt, I must rush to the defence of my late father's close friend Arthur, and suggest that you'd have to get up very early in the morning and travel a huge distance to find anyone coming close to the Mallock family's expertise in the realm of live rear axle location! For years they have built just about the fastest live-rear-axled track cars around.

As for the A-bracket being attached at the centre of the axle, it doesn't really matter much, though the photo of the A35's underside is pretty close. I've seen where the attachment is way over to one side of the axle, and still provide good lateral location.

By the way, the Mumford is a long way from a Watt's linkage in performance and control of roll-centre height.
 
Roger: I don't mean to insult anyone and my understanding of race suspentions is next to nil. I was just going by my observations of the linkage's and on further reading I see that the object of both is to lower roll center. Since I've never had an oportunity to compare the influence of different roll centers by the "seat of my pants" I don't realize the importance of that. Right off the top of my head it would appear to me that the ideal roll center would be in the center of the axle. The lower you get it the more body roll you would experience. Please enlighten me as to why those design's are so important. Colin Chapman didn't do many things wrong!


Kurt.
 
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