wheel hopp - Page 2

decooney · #21 (**permalink**) 10-20-2003, 07:59 AM

rdorman,
Yes, my last car was a Unique, and the tri-bar setup (once added) made a huge difference in handling and predictability. This comes standard now on the Unique cars. All solid mounts.

Bob,
Thanks, we look forward to the details on your design.

rdorman · #22 (**permalink**) 10-20-2003, 09:42 AM

Also the lower a-arm inner bushing where solid and not rubber?
Thanks
Rick

decooney · #23 (**permalink**) 10-20-2003, 10:32 AM

Quote:

Originally posted by rdorman

Also the lower a-arm inner bushing where solid and not rubber?
Thanks
Rick

- Stock bearings, stock steel shims, stock rubber separators. Never tried the solid bushings on the Unique, worked okay as-is with the rear tri-bar setup. If you don't have it now, I can tell you for certain it was the best investment I ever made to my Unique and the results were excellent; especially when on the throttle coming in to a turn and even more so coming out of a turn. Before that it felt like the Jag IRS in the Unique was sort of flopping all over the place under load and over bumps, etc.

Jim Holden · #24 (**permalink**) 10-20-2003, 10:48 AM

Folks:

ERA's setup is designed to duplicate the Jag setup. ie rear in a cage with trailing arms, etc.

Jim

decooney · #25 (**permalink**) 10-20-2003, 11:01 AM

Hi Jim,

Agreed, IMO - thats the problem. The objective of this thread is to inquire and resolve how to "eliminate" wheel hop. Are you possibly implying that your ERA Cobra(s) do not wheel hop under heavy acceleration / tire spin? If you by chance have a simplified solution, we're all ears... ?

I know four people with ERAs that this problem to resolve, me included with Mike. All with different tires, shocks, same problem. Hopefully Bob P's dampner design-to-be will do the trick.

Hey Mike,
I'm about ready to put a remote camera eye under there to record it and see what's really moving around. I bet its the cage. If nothing else works, I may resort to some sort of tri-bar configuration. Waiting to see what Bob comes up with first.

rdorman · #26 (**permalink**) 10-20-2003, 12:08 PM

You have certainly sold me. I am going to try and get as much suspenstion upgrades in this winter as time and money will allow. Do you recall what Unique charged for the parts?
Rick

Jim Holden · #27 (**permalink**) 10-20-2003, 03:27 PM

dec:

I do have the ERA outboard brake rear on the FIA. I don't know if the extra link makes a big difference or not. And I do not hammer my cars around. When you have your left$lung tied up in them, it's hard for me to abuse it. That said, I never noticed a problem on my first two 427sc's. I was younger then and less hesitant about and opportunity to nail it.

Jim

ERA 626 · #28 (**permalink**) 10-20-2003, 03:58 PM

easy Jim... we dont need that here.

decooney · #29 (**permalink**) 10-20-2003, 04:13 PM

Quote:

Originally posted by rdorman

You have certainly sold me. I am going to try and get as much suspenstion upgrades in this winter as time and money will allow. Do you recall what Unique charged for the parts?
Rick

rdorman,
No problem, I enjoyed my UM Cobra tremendously! When I purchased it, the entire trailing arm/brace kit was $275 - total. May be more now... Included the two center square tube rods/plates, rear bracket to be welded to the frame (small), two long round rods for the sides, and the heim joints on each end, all powder coated. I looked at it as if the parts were free because there was certainly more than $275 in labor time just to make the parts. Say hello to the Unique folks for me. Great people and always willing to help.

decooney · #30 (**permalink**) 10-20-2003, 04:42 PM

Hi Jim,
That's understandable. I don't hammer or cruise my car either. I wax it once every three months, maximum. Driving is 1st priority, and worring about it definitely comes last. But then if one considered 1/3 throtte "accidental" tire spin and wheel hop to be hammering the car, I guess I would then have to go trade my Cobra in on a Honda S2000 to prevent that from ever happening again.

That'll never happen. Have Fun!

foothills gary · #31 (**permalink**) 10-20-2003, 05:53 PM

I am thinking of going to the optional rear ERA suspension when I order my car because of the extra trailing link on each side.Has anyone put this setup in a 427SC ERA,and does the wheel hop issue arise with it? Gary

Jim Holden · #32 (**permalink**) 10-20-2003, 07:04 PM

dec:
If you're getting "wheel hop" at "1/3" throttle, then something is wrong. ERA owners drag race their cars and don't have a problem. My big block cars did not have a problem. Something must be off either with alignment, adjustment or the dif itself. The dif in my first car was a Torsen and that worked extremely well. The tires on my first car were Goodyear NCT and on the second, Hooziers.

Jim

fordracer · #33 (**permalink**) 10-20-2003, 07:05 PM

I don't have an ERA yet but I do have an assembly manual, does that count ??? Maybe Bob will chime in here but how does the subframe mount to the frame ? Is it rubber, urethane, or solid metal ? I would think replacing rubber subframe bushings with urethane would help a lot. Urethane with harder urethane or steel/aluminum ? How about where the trailing arms mount to the frame ? Is there rubber there too ? If I'm reading the manual correctly the lower control arms have roller bearings so there should be no deflection there.

Bob Putnam · #34 (**permalink**) 10-21-2003, 03:59 AM

The subframe is rubber mounted, while the trailing arms use urethane bush at the front and a rod end at the rear. It is not possible to mount the subframe rigidly. To do so would put the suspension pieces in bind.

fordracer · #35 (**permalink**) 10-21-2003, 05:44 AM

Can't the subframe be mounted in urethane. I know it's not an ERA, but I've done a number of '03 Mustang Cobras with IRS with severe wheel hop. We replace the rubber subframe bushings with urethane. It makes the ride a little stiffer and a little bit more noise but wheel hop is about 90 % cured.

Bob Putnam · #36 (**permalink**) 10-21-2003, 06:55 AM

Quote:

Originally posted by fordracer

Can't the subframe be mounted in urethane. I know it's not an ERA, but I've done a number of '03 Mustang Cobras with IRS with severe wheel hop.

The ERA (Jag-based) design is completely different from the Mustang. The subframe mounting must be slightly flexible.

CJ428CJ · #37 (**permalink**) 10-21-2003, 07:03 AM

I'm running Michellin Pilot Sports and the standard inboard brake rearend in my ERA. I had a mild wheel hop problem when I first got the car running but I stiffened up the rear dampers about 2-3 clicks and the problem has disappeared completely. So, as Bob has indicated, the problems seems to be a bit mysterious and apparently different on each car.

Chris

decooney · #38 (**permalink**) 10-21-2003, 10:21 AM

Chris,
I noticed the same thing. I can set 4-5 clicks tigher on the Spax and it helps, at the sacrifice of ride quality. If I raise the air pressure, it helps some too but I won't leave it this way.

My car has had a 4-wheel alignment twice. So, I just don't get on it at all 'til the car is up to speed - not wanting to damage anything from wheel hop. I'm running a fairly pumped 428CJ/550hp, with the Good Year Eagle tires. They stick really well, but seem to contribute to the problem some - IMO... If I had to do it again, I'd even consider a milder motor with less torque next time. HP & Torque is great if you can utilize it.

Hopefully we can all come up with a set of adjustments or changes that will help the wheel-hop situation. Thanks!

ERA 626 · #39 (**permalink**) 10-21-2003, 04:12 PM

Duane,
I am anxiously awaiting Bobs fix for this problem.

cobra · #40 (**permalink**) 10-21-2003, 10:16 PM

dec:

I have mounted the optional rear ERA suspension on my ERA and I had never a problem with wheel hopp.

Greetings from Switzerland

Walter