Radius rod bolts

[butch27]

Crazy to ask this after the car has been running for so long. On the bolts that bolt the radius rod clevis's on to the bat wings-- Should they be really tight OR slightly loose to function.?? Thanks

 

[2old2fast]

I'll assume they're hairpins ???? yes... tight.
dave

 

[TriodeLuvr]

I tighten mine just to the point where I think the nuts won't back off. I also use blue loctite. IMO, this is an area of our cars that needs a redesign using bronze sleeves or urethane bushings.

 

[vand]

Wyh not use nylock nuts? They will stay put no matter how tight or loose they are.

 

[railroad]

Be sure to get a minimum of 2 threads showing through the nut on nylock or fiber lock nuts. I think steel lock require a thread and half. I know that sounds picky, but that was the minimum on aircraft, (steel lock).

 

[bobs66440]

Right, I never thought of that. If they are too tight, they will bind. Hmmm.

I was reading the Speedway Motors assembly instructions for their kit and it says to tighten them to 20 ft. lb.

 

[2old2fast]

How can something that is stationary [does not move about the axis of the fastener ] bind ??
dave

 

[baddawgcustoms]

Right, I never thought of that. If they are too tight, they will bind. Hmmm.

I was reading the Speedway Motors assembly instructions for their kit and it says to tighten them to 20 ft. lb.

If your using harpin setup the clevis on the front shouldn't move at all when the axle travels, only the heim on the rear will move. I would definitely go with the speedway recommendation at 20lbs. No way for a hairpin to bind in the front, you WANT it to be locked in place. 4 bar has to be loose to move but not hairpins.

 

[butch27]

I have a 4 bar with clevises on the bat wings and Heims on the frame mounts.

 

[2old2fast]

In that case your setup was not designed correctly. Clevis's are not designed to rotate [for suspension use] & should be replaced w/ either a rod end [heim] or a bushing w/ a sleeve .
dave

 

[baddawgcustoms]

In that case your setup was not designed correctly. Clevis's are not designed to rotate [for suspension use] & should be replaced w/ either a rod end [heim] or a bushing w/ a sleeve .
dave

Dave is absolutely right. A clevis should never be use on 4 bar. They are not designed to move. About the only thing you can do is swap the front out with heims so it can have some travel. As long as you have NO lateral movement in your axle the heims should work fine. Are you using a panhandle bar or what type spring setup are you using?

 

[baddawgcustoms]

Dave is absolutely right. A clevis should never be use on 4 bar. They are not designed to move. About the only thing you can do is swap the front out with heims so it can have some travel. As long as you have NO lateral movement in your axle the heims should work fine. Are you using a panhandle bar or what type spring setup are you using?

 

[bobs66440]

If your using harpin setup the clevis on the front shouldn't move at all when the axle travels, only the heim on the rear will move.

Ok, right. I get it now...

Hey, this is my first time setting up a hairpin suspension with clevises.

 

[baddawgcustoms]

Ok, right. I get it now...

Hey, this is my first time setting up a hairpin suspension with clevises.

Me too Bob! Trust me I'm not speaking from experience, only from hours upon hours of reading since I started this project. I've spent the better part of this last year planning this car and reading book after book and forum after forum. Ron at RPM just shipped my front end stuff today with extra long hair pins so I had just read up a lot on front chassis geometry and design!

 

[bobs66440]

Ha ha, yes! I think there's more hours spent in research than actually working on the car!

 

[butch27]

I'm changing to Heims.

 

[Francis Blake]

I will say something that everybody probably knows, make sure you use large washers on the outside for safety, and tighten the bolts that goes through securely and use locking nuts on them. Merry Christmas to everybody.

 

[Screaming Metal]

I'm not a suspension expert, I deal with motors and drivetrains. BUT, as I do have a Engineering background, please do as Francis said, washers are needed on the sides. The lateral thrust needed to pop a heim out isn't much, especially if they are the nylon/propylene surround on the spherical ball. Plastic compresses. The old style with the crimped capture of the spherical ball was much better and could take alot more pressure (heavy duty). They had to be lubed though, hence the plastic (light duty).
Also, the Nylocs are a wise choice to keep nuts from backing off. This is just my 2 cents here, but I like to use 'crimp nuts', the ones that either have the edge crimped slightly or the crimped middle area.
After many test fits to make sure all is as it should be, I do final assembly with the crimp nuts going on, and a touch of loctite to help assure holding.
The loctite actually lubes the threads slightly to ease the installation of the nuts, and just a touch stays in the threads for additional holding power. The majority stays at the outter threads, assuring that things will stay put....
The metal to metal contact is a good thing, in the fastener world....

 

[butch27]

I DO cotter pin all suspension parts.

 

[2old2fast]

Lacking an engineering degree , I can only relate to my experience , my car now has 37K miles on it , heim joints on the rear radius rods, heim joints on the front radius rods , heim joints on the drag link & tie rod , 1/2" in font , 5/8" in rear , nothing has failed , loosened , or caused any other problems.... I feel they are safe !!
dave