Rear Radius Rods

[thomas]

I took my car for a ride the other day, gave it some gas and rolled the rear radius rods. What I got with my kit from Spirit was four 27" hair pin radius rods. They get there radius rods from speedway. When looking in the speedway catalog, I noticed that they are made for front suspensition. I called speedway and they told me that the rear radius rods should have a brace welded at about the center of the radius rod to keep it from twisting. Spirit is sending me new radius rods made my RPM. So, RPM should I weld a brace to those radius rods when I get them. Spirit said they are a much better radius rod and that I really do not need to. I'm just thinking it wouldn't hurt if I added some extra strength to them.

Do wish I could get on the site more often, but I'm still having problems with my computer.

thomas

 

[RPM]

You won't need any bracing in those new rods. They are made from 1" tube instead of that 7/8".

 

[thomas]

Thanks Ron.

thomas

 

[putz]

How do the yokes on the drive shaft look ? If they went to far the joints could have bound up.

 

[butch27]

Thomas: What the heck were you doing? Have the windshield on yet? Going to Bonneville Tue. Butch

 

[Youngster]

Good point Putz. Thomas, I know you'll check everything over before you hit the road again. I think I would install new u-joints anyway.

Ron

 

[GT63]

I took my car for a ride the other day, gave it some gas and rolled the rear radius rods. What I got with my kit from Spirit was four 27" hair pin radius rods. They get there radius rods from speedway. When looking in the speedway catalog, I noticed that they are made for front suspensition. I called speedway and they told me that the rear radius rods should have a brace welded at about the center of the radius rod to keep it from twisting. Spirit is sending me new radius rods made my RPM. So, RPM should I weld a brace to those radius rods when I get them. Spirit said they are a much better radius rod and that I really do not need to. I'm just thinking it wouldn't hurt if I added some extra strength to them.

Do wish I could get on the site more often, but I'm still having problems with my computer.

thomas

I've seen this happen several times. I, for one would have at least one brace between the bars. Mine are 1" bars and they have the brace in them.

 

[donsrods]

Hmmmm, you got me to wondering how ours are done, so I pulled up some pictures to have a looksee. The ones on my '27 are very heavy 1 inch tubing and have no braces, but the ones on my Son's T do have braces, and are slightly thinner. I abused the ones on my T for a lot of years and many hard launches, with no problems, so I guess the heavier tubing is the key.

Don

 

[hulkamania]

We have used Speedways radius rods for 10 years and had no problem until this year. Speedway used to have the radius rods made in United States but now they are made in China. We have taken care of the problem and do not use those radius rods now. We have RPM (ron pope) making our radius rods. We know they are made in the U.S. You couldn't bend those monsters. They are 1" thick instad of 7/8" thick.

 

[donsrods]

Yeah, "Pope" doesn't sound like a Chinese name to me. :lol:

Speedway is going to more and more chinese stuff........really sorry to see that happen as some of it is really crap.

Don

 

[RPM]

The ones on the back of my tub are 36" long, and while it ain't no race car. We did a lot of burn outs with it at the BASH and have done a lot elsewhere. They don't have a brace, and have had no problems with em. You can put a brace in em if it makes you feel better but it is not needed.

 

[Lee_in_KC]

Hey Ron, maybe if your radius rods weren't so massive you wouldn't have blown your tranny!!

 

[GAB]

I don't think that gobs of horsepower are the culprit in bending radius rods as much as lack of power is. Plenty of hp just breaks the tires loose and the locating devises are just pretty much just along for the ride. Lack of hp transmits the rotational forces where the pinion gear tries to climb the ring gear and the these go through the radius rods. 4 bars have tension and compression forces instead of bending loads.

Just my thoughts.

 

[Youngster]

I agree with George here. Back in the day when we were running a Hilman in modified production, we were having trouble getting enough traction off the line. We went to wider slicks. More traction but bent the bejebbers out of the rear hair pins. We found a happy medium buy trussing the new hairpins. Then the rear end scattered. Always a way for Murphy to show up.

Ron

 

[RPM]

Hey Ron, maybe if your radius rods weren't so massive you wouldn't have blown your tranny!!

I got the tranny fixed, only had a stuck valve.

 

[thomas]

Once I recieved the radius rods made by Ron Pope, I realized I do not need a brace. Great product Ron. And by no means I'm I taking anything away from Spirit Industries, they are a great org.

thomas

 

[der Spieler]

I'm thinking rear gear ratio might be a factor too. I had a 3.70 gear in mine when I first built it but I changed over to a 3.00 gear for mileage. With the 3.70 gear I could pretty much boil my big M/Ts. With the 3.00 it was a lot harder to turn them over. I was at a car show several years ago and they were doing burnouts on a real rough concrete surface. I did two and then managed to rip the radius rod mounting bracket off of the rearend housing. I figured it was a combination of a tall gear, big tires and a very grippy surface. Steve

 

[Ted Brown]

Don I see in the pics of your chassis, that FIRST, you have the top tube hanging out from the bottom tube, if you ever build a new set, try and keep the two the same length, that way they are much stronger, and us at least a 5/8 bolt to a 4bar type bushing to the end of radius rod. I have seen many just snap off at the threads of the Heim or whatever type of end you use...
Plus on the Blue chassis, I hope you are going to raise the rear Trans mount up for a lot better alinement for the driveshaft. a special secret that I do with short driveshafts, that want to bind with little movement, is to cross the ends exactly 90 degrees, as the U joints are dumb when all is said and done, just a bit harder to make that way, to get perfect.. also great with steering shafts, no more binding... or breaking. My shaft is only around 10 inches long... and I have a real soft ride... rubber snubbers at both ends of the ride, (up and down)

 

[Ted Brown]

I'm thinking rear gear ratio might be a factor too. I had a 3.70 gear in mine when I first built it but I changed over to a 3.00 gear for mileage. With the 3.70 gear I could pretty much boil my big M/Ts. With the 3.00 it was a lot harder to turn them over. I was at a car show several years ago and they were doing burnouts on a real rough concrete surface. I did two and then managed to rip the radius rod mounting bracket off of the rearend housing. I figured it was a combination of a tall gear, big tires and a very grippy surface. Steve

It was probably that fact that you used solid type ends in your radius rods, I would bet.. if you drive on the street much. whenever the car leans, it is trying to rip the mounts out of the rearend housing, and they are the weekest point, so that is another reason to make your brackets go all the way around the housing, and always use rubber bushings to mount them.. I like to run as tall a gear as the engine can pull... As far as too much low end, that is what larger diameter exhaust pipes will cure.

 

[Youngn]

i have a four link setup on my t bucket and was wondering if this could happen to this type of setup too.