Suspension Notice for S/SS by NHRA

[BBF67]

Since the strut rod swings in an arc as the suspension goes through its full travel from extended to compressed, would a solid fixture such as a heim or ball type bushing on one end of the strut rod cause the cars alignment to change throughout the swing of the lower control arm?

[Jeff Lee]

Originally Posted by BBF67

Since the strut rod swings in an arc as the suspension goes through its full travel from extended to compressed, would a solid fixture such as a heim or ball type bushing on one end of the strut rod cause the cars alignment to change throughout the swing of the lower control arm?

No.

[Bill Harris]

I think I would want to see a metallurgical study of that fracture before I assumed that it was a shear and not tensile break. I don't want to be the one that finds out when one lets go. The poly bushings are much more resistant to vertical motion than either the rubber or spherical, but I have used them (Prothane) in the past on my '71 Mustang and have been able to pull the strut into position on the lower arm with one hand so they aren't that bad. I have a hard time seeing that the bushing could exert enough bending force to shear a strut rod even though there is more side loading than with the alternatives. Has anyone had one just bend without breaking?

I don't know of any aftermarket strut rods that are advertised as being tougher than the OEM and are direct replacements. Opentracker has a unit that looks fairly stout that might ease my mind, for one...

http://www.opentrackerracingproducts.com/strutrod/

[Paul Precht]

Are the B and E body Chrysler cars suffering the same issues as the Fords.

[Peter Ash]

Originally Posted by Bill Harris

I think I would want to see a metallurgical study of that fracture before I assumed that it was a shear and not tensile break. I don't want to be the one that finds out when one lets go. The poly bushings are much more resistant to vertical motion than either the rubber or spherical, but I have used them (Prothane) in the past on my '71 Mustang and have been able to pull the strut into position on the lower arm with one hand so they aren't that bad. I have a hard time seeing that the bushing could exert enough bending force to shear a strut rod even though there is more side loading than with the alternatives. Has anyone had one just bend without breaking?

I don't know of any aftermarket strut rods that are advertised as being tougher than the OEM and are direct replacements. Opentracker has a unit that looks fairly stout that might ease my mind, for one...

http://www.opentrackerracingproducts.com/strutrod/

X2 on the metalurgy.

Parts can have minute fractures for long periods of time before a "Montreal " size pothole causes total failure.

Dye-checking strut rods may be in the future for those requiring their own and others safety.

[MLP]

This is the NHRA at it's worst! I would really like to see some response from them as to why this was done.

They allow aftermarket disc brakes that are a performance advantage over factory drums due to weight savings because they are much safer. I understand why they allow them and nobody disputes the importance of having adequate braking at high speeds with heavy cars. What's more important than high speed steering and braking in a race car?

So considering that the strut rods and their bushings directly affect high speed steering/handling and braking, shouldn't they be held in the highest regard in terms of safety and the implementation of new rules? Especially when the modifications in question offer no performance advantages?

My Belvedere at 3500 pounds going 130 mph (hoping) in A/S doesn't have the same safety concerns as a SS/J car? Just admit you dropped the ball NHRA and fix this before someone in a real fast heavy stocker gets hurt for absolutely no good reason at all.

[Tom Nolan]

I was told that if wheel stands are a problem, with safely controlling the movement with stock OEM rubber bushings & strut rods, wheelie bars are legal in stock....use 'em! Well anyone that has tried to hook a heavy high powered stocker on a 9" tire knows if the wheelie bars touch the ground the car's tire will unload. I can get away with riding the wheelie bars for 30' on my super stocker because it has a big fat tire.... 2 different animal's. If the majority here {poll results} are OK with aftermarket strut rods who is advising NHRA tech to not legalize after market strut rods in stock? After all it's OK to have after market strut rods on a SS/MA car and not for a A/SA ???? Where is the common sense?

[69Cobra]

Exactly! I'm curious after looking at the entry list for Pomona and seeing all the brake strut rod cars that are pre entered, if they all are going to show up with rubber bushings, especially Calvert.