wheel hopp - Page 5

mr0077 · #81 (**permalink**) 11-11-2003, 07:46 AM

Mike, I think he is talking about the add-on horizontal "snubber" shocks, not the coil-overs you're using for suspension on the rear end.

decooney · #82 (**permalink**) 11-12-2003, 07:06 PM

BP, Mike,
...discussed the setup and implications of this type of fixture arrangement with a few colleague engineers. The CNC man believes a more secure mounting fixture would be required on the top of the Jag hub; concluding the hub/case material surface area and thickness on top, with such a small mounting bracket, might just shear the top of the hub/case right off (if bolted on)unless it was welded and re-enforced. Soft Aluminum too.

So, I'm working with the CNC/Machinist to see what other fixtures could "reasonably" be made to wrap around the hub-case a bit more using the main body of the hub for added mass and strength. I'm not sure if you buy in to this or not, but I'm going with their recommendations and will keep drilling down more.

Mike
No this would be an extra shock. One for each side. It goes from the back of your frame to the top of your outer hub case with some brackets that would be made. You would keep your spax; no change there. I'm plugging away on it time permitting after work and weekends. I meet with the machist again this weekend. More information as I get it.

I may be going a little slower on this than others need, so please don't wait for me. If we can come up with something thats worth testing, I'll be a first guinea pig to help prototype it. I'm trying to see how the pieces can be made affordably, but there will be some extra labor on the hub/case fixture that I did not anticipate. We'll see...

strictlypersonl · #83 (**permalink**) 11-13-2003, 03:17 PM

If everything works as designed, the forces will actually be quite small. The link does not transmit wheel torque - its only function is to damp out any natural oscillations from the compliance. Even so, I spread the hub carrier load over about 4".

Ideally, the bracket should be welded on, but I'm trying to make it easier to retrofit.

mrud · #84 (**permalink**) 11-14-2003, 04:36 AM

Bob,
Are the cars you are presently building going to have the modification?

strictlypersonl · #85 (**permalink**) 11-14-2003, 01:38 PM

Quote:

Originally posted by mrud

Bob,
Are the cars you are presently building going to have the modification?

No. In spite of the visibility of this thread, the problem is rare when everything is set up correctly. If you have a problem that can't be resolved conventionally, then we'll talk.

decooney · #86 (**permalink**) 11-15-2003, 01:59 PM

Mike,
Spent some time with my machinist friend today. Took him a hub and some diagrams from BP along with some others... Looked at some options for inserts and insert/tools for mounting the frame bracket to box-tube frame. He felt it might be safe to thread the hub if its just for a dampner support. Also stopped by the Ford dealer to check out the dampner; but they were out. Time permitting, I hope to make a mock-up model once I get a dampner with spherical rod ends. May need to make that or have one custom made. Hope to get more time on it in a week or so. See Ya. Duane

BP,
Any other ideas on what might not be "set up correctly?". I'd prefer to fix the problem vs. adding more hardware to the car unecessarily. At first, I thought it was my tires aggravating the situation, but thats not the case with the varying tires showing common results... Shocks?, Adjustment?, Springs?, Subframe bushings?, sway bar or adjustment?, any other ideas? Meanwhile, I'll keep working on the dampner approach in absense of a solution or possible fix.
Thanks! Duane

decooney · #87 (**permalink**) 11-22-2003, 02:09 PM

Mike,
cc: BP,
Got a quick update on the gadget development. Was lucky enough to spend 1/2 day today working on the templates for the prototype fixtures on the hub, chassis, and design for a smaller, more custom-fit dampner. I'm leaning away from using the stock style Mustang quad-shock dampner at this point.

We are focusing more on quality and strength, but looking at a few different ways to help ease installation a bit in case we replicate a handful of these kits for individuals, ERA, or if anyone wants them. Still doing this on the side, time permitting. If it proves to work out well functionally, we are even looking at maybe doing some in CNC/Billet fixtures vs. steel as a second option. Talk to you in a 10-14 days. Duane

ERA 626 · #88 (**permalink**) 11-22-2003, 02:27 PM

Thanks Duane,
Keep us posted.

decooney · #89 (**permalink**) 01-20-2004, 11:06 AM

Mike/Bob,
Sorry I've been out of comission a bit on this project after the holidays, and due to a slight hand/finger injury from a dirt-bike incident. Argh. Anyhow...

Update: Prototype version 3 is almost complete for a bolt on and trial in a few weeks. Man, I need my freakin hand! If I can get some help from my friend, I'll let you know if I can do the install and some back road one hand driving to test it out. I don't know how it will test out but it sure looks important back there during the test-fits. Looks clean and simple. Had to go all metal vs. billet. Trying to make it drill/tap & bolt-on vs. weld-on. Coming along now...

decooney · #90 (**permalink**) 02-01-2004, 12:49 AM

Hey Mike,
Version 3 prototype kit is mounted now with all revisions complete. All hubs have been drilled, riv nuts installed into the frame, shocks and everything test fitted perfectly. Looks good so far. When I get my cast off my hand, the test drive begins. We'll see in a few weeks I hope...

ERA 626 · #91 (**permalink**) 02-01-2004, 08:06 AM

Thanks Duane... I hope it works

decooney · #92 (**permalink**) 02-01-2004, 09:50 AM

Mike, Me too... what seemed like a small suspension mod has turned out to be a bit of an R&D projelect x3. Sure looks cool though and like it belopngs there, with plenty of tire clearance now with this new design. Can't wait to try it and soon.

DC

clayfoushee · #93 (**permalink**) 02-01-2004, 10:11 AM

Hi Duane,

At the risk of re-opening a hypothesis that's already been discounted, does the double-triangular trailing arm set-up standard on Uniques, not work for ERAs, both of which utilize the Jag rear-end?

As you said much earlier in the thread you never experienced the problem on your Unique, and I've never heard an owner of a later model Unique even bring up the issue, although they do talk about burning rubber a lot. I've encounted the hop on a lot of different cars, but never on my Unique.

decooney · #94 (**permalink**) 02-01-2004, 10:31 AM

Hey Clay,
You are correct, and I agree. However, my ERA car/fuel tank hangs low (beneath the trunk), so to do this the tri-bar support rod setup would have to be pretty low and angled like a hook around the tank. The rear mounting fixture would be sort of obscure hanging down. I may still do this as well as an addition to the absorber project. Cobras always need something somewhere and I seem to be a glutton for punisment and drawn to it.

clayfoushee · #95 (**permalink**) 02-01-2004, 10:59 AM

Duane,

You're right...that wouldn't work well. I just hadn't seen the answer previously in this thread.

decooney · #96 (**permalink**) 02-15-2004, 02:39 PM

Hello Mike L, Bob P, others,

Got an update for you or others that have been following this thread for the ERA Jag IRS upper link/dampner kit. a.k.a WHK-ERAD01.

The final has been mounted and tested; version 2.5 to be exact. It includes a 50/50 horizontal dampner, with solid mounted steel only fixtures to the Jag hubs and to the rear part of the chassis. I have about 100 miles on the car now driving in varying road conditions and surfaces. The 2nd prototype has a few design changes for ease of installation purposes. It includes 4 tapped holes/bolts to mount the front hub brackets, 4 bolts to mount the rear frame brackets; two being Rivnuts for the frame, the other two using existing holes. Here are the final results, using my GoodYear Eagle tires and Spax Coilovers:

- From a roll, stabbing it to the floor about at about 8-15 mph, the tires bite harder now, and there is no wheel hop with less tire spin on my tests. You do feel the car lurch forward in a different manner. Even when just taking off from a stoplight you notice something is different. Subtle, but you do notice a change.

- Out of turns you notice it grabs differently or sooner, and I can't explain it really, you'd just need to drive it to see what I mean. I have to get use to how it behaves again out of turns. Feels like there is a bit less slop now and the rear almost comes around just a tad bit quicker, like its more planted somehow. Can't explain it in words really.

- From a dead stop or at 1mph launch shock loading the rear end, it still wheel-hops enough to complain, but not as irratic as before; I'd say an easy 50% reduction under a harder launch. I only tried this once and don't want to try this again...

- The actual measured travel on the dampner itself (how much it acutally moves or dissapates) is about 1/4 inch each way. This to me says there is up to 1/2" movement on the hubs of these cars, even when there is a dampner.

I guess my next test will be to go back to the subframe, retorque all bolts, check control arms, add some air to the rear tires, and go 2-3 clicks firmer on the Spax shocks and call it a day.

In summary, I would say that it makes a noticeable or moderate difference in a few different ways, however wheel hop is not completely eliminated on hard launches; only soft launches after testing it with my tires and shocks. It looks like it belongs there... Your tests may behave differently using your tires/shocks, etc. Its a bit of work to drill/tap and install and get everything properly mounted for both brackets on each side. The whole kit may only be worth doing for 1 out of every say ten ERA owners out there; but I like it so far.

At this point, I'm not going to make any further changes to the design and will just go with this in its final form as it is today.

Take Care.
Duane

ERA 626 · #97 (**permalink**) 02-15-2004, 04:57 PM

I have to save for this stupid bond, then the brake & light inspection, the a new windshield :-( just driving down the road when I noticed a crack going right up the middle no idea how it got there

Duane how much will this cost? I am intrested to say the least.

decooney · #98 (**permalink**) 02-15-2004, 08:59 PM

Hi Mike,
Let me total up the cost of the dampners, materials, and labor/machinist time, bits/pieces for everything, and we can come up with a price. I'd prefer to just make up two to three more kits for now, have you try them, and get your feedback first before doing any more... Lets email/PM about it end of next week. Thanks, Duane.

ERA 626 · #99 (**permalink**) 02-16-2004, 07:33 AM

Duane,
let me know...

hoppy · #**100** (**permalink**) 04-04-2004, 08:25 PM

Hi Guys,
Today I finally had time to get my car up on stands and check the rear suspension set up per conversations and instructions from/with Peter and Doug at ERA.

The trailing links needed about 3/8th inch more thread through the nut.

The shocks were all (4 rear and 2 front) set "full soft" (screws all backed out all the way)

Tires all at 35 lbs of pressure.

I adjusted the trailing arms, set the shocks at 7 quarter turns in and dropped the tire pressures to 28 front and 26 rear.

I didn't have the time or safe place to fully test the results but the little bit of "aggressive" driving I did manage to fit in showed very dramatic improvement in reducing the wheel hop as well as getting a lot more power to the pavement.

I am looking forward to finding an opportunity to wring it out and see just what I have here.

I am also looking forward to any reports from those that are installing Duane's traction device.

I am really having a good time "messing about" with the various aspects of this greatest toy ever and although I ran out of $$ a long time ago, I will continue to squirl away my lunch money for improvments and accessories. Had a glove box installed this week and ordered some anti submarine belts and high intensity lights last week along with a knock off fixture and floor mats.

Does it ever end? I hope not!