Author Topic: Near solid mounted front axle  (Read 13403 times)

0 Members and 1 Guest are viewing this topic.

Offline Mr. Schimstock

  • Full Member
  • ***
  • Posts: 132
Near solid mounted front axle
« on: April 15, 2015, 08:15:03 PM »
I've read some of the threads regarding having or not having a front suspension.  For the purpose of this thread I'm talking about an XO lakester.  I see the benefits of the rigidly mounted front axle (no suspension) but would have concerns about the increased loading from a complete lack of compliance and issues with stress concentration at the mounting points.  Has anyone considered mounting a front axle on some high durometer rubber isolators.  My thinking is that this would allow the absorption of some to the loads and vibration but limit movement of the axle to less than something like .25" It would be somewhere between a suspension and a rigid mount, or maybe a very high spring rate short travel suspension. There are different styles of isolators that could be used to change spring rate in different directions (fore-aft vs vertical).  The isolators typically have some natural damping so I think it would bounce much.
Sproing, crack, ouch!

Offline RichFox

  • Hero Member
  • *****
  • Posts: 2663
Re: Near solid mounted front axle
« Reply #1 on: April 15, 2015, 08:37:36 PM »
You might talk to Jack Costalla about this. Jack has used a similar deal.

Offline SPARKY

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 6908
Re: Near solid mounted front axle
« Reply #2 on: April 15, 2015, 10:51:49 PM »
I chose solid but 1/4" to 1/2" would not bother me---I think this would make sense
Miss LIBERTY,  changing T.K.I.  to noise, dust, rust, BLUE HATS & hopefully not scrap!!

"Security is mostly a superstition. It does not exist in nature, nor do the children of men as a whole experience it. Avoiding danger is no safer in the long run than outright exposure. Life is either a daring adventure or nothing."   Helen Keller

We are going to explore the racing N words NITROUS & NITRO!

Offline Milwaukee Midget

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 6662
    • Milwaukee Midget Racing
Re: Near solid mounted front axle
« Reply #3 on: April 15, 2015, 11:19:01 PM »
I've read some of the threads regarding having or not having a front suspension.  For the purpose of this thread I'm talking about an XO lakester.  I see the benefits of the rigidly mounted front axle (no suspension) but would have concerns about the increased loading from a complete lack of compliance and issues with stress concentration at the mounting points.  Has anyone considered mounting a front axle on some high durometer rubber isolators.  My thinking is that this would allow the absorption of some to the loads and vibration but limit movement of the axle to less than something like .25" It would be somewhere between a suspension and a rigid mount, or maybe a very high spring rate short travel suspension. There are different styles of isolators that could be used to change spring rate in different directions (fore-aft vs vertical).  The isolators typically have some natural damping so I think it would bounce much.

Granted, it was independent, and operated through levers, but the original Mini Coopers used rubber cones with great success for 50 years.

As long as you can keep everything on the horizontal planes in check, all you'd really need would be what you're talking about, but the caution I have is this - Would the inspectors consider it a sprung suspension, which then requires shock absorbers on each wheel?   :?

I think you could get by with it if you were to mount the axle with large diameter isolation bushings.
« Last Edit: April 15, 2015, 11:22:25 PM by Milwaukee Midget »
"Problems are almost always a sign of progress."  Harold Bettes
Well, I guess we're making a LOT of progress . . .  :roll:

Offline kiwi belly tank

  • Hero Member
  • *****
  • Posts: 3132
Re: Near solid mounted front axle
« Reply #4 on: April 16, 2015, 09:41:19 AM »
Thats quite doable & has been done a few times. Thrust II had rubber cone suspension copied from the Mini. The Herbert Steen liner was suspended with a stack of Belleville Washers. SCTA would likely view it as suspended & require shocks. The rule doesn't say how effective they have to be! :roll:
  Sid.

Offline bearingburner

  • Sr. Member
  • ****
  • Posts: 511
Re: Near solid mounted front axle
« Reply #5 on: April 16, 2015, 12:33:34 PM »
Front ends suspended by rubber biscuits were used by dragsters in the late '50s early '60s. Chassis Research sold One

Offline Dynoroom

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 2192
Re: Near solid mounted front axle
« Reply #6 on: April 16, 2015, 01:29:54 PM »
We were going to run front suspension originally but ran out of time & room. Not saying it's right but our car has a solid mounted axle. Has run at El Mirage & Bonneville since 2008 with no problems. 175" Wheel base & 3500 lbs. 240+ mph
Michael LeFevers
Kugel and LeFevers Pontiac Firebird

Without Data You're Just Another Guy With An Opinion!

Racing is just a series of "Problem Solving" events that allow you to spend money & make noise...

Offline saltracer1

  • Full Member
  • ***
  • Posts: 194
Re: Near solid mounted front axle
« Reply #7 on: April 16, 2015, 06:08:04 PM »
I remember seeing a modified roadster with a suspension setup like you are talking about back in something like 1998, came back a couple of years later and he had made it solid. All I remember was the car was Toyota powered and blue in color.

Offline Mr. Schimstock

  • Full Member
  • ***
  • Posts: 132
Re: Near solid mounted front axle
« Reply #8 on: April 16, 2015, 08:59:22 PM »
Thanks for the input.  I think I'll give it a shot and build in some "friction shocks" in the locating arms.  If it gives me any concern during any runs it will be easy to change the stiffness or just swap out the rubber for some metal and voila... solid mount.

Sproing, crack, ouch!

Offline dw230

  • Hero Member
  • *****
  • Posts: 3165
Re: Near solid mounted front axle
« Reply #9 on: April 17, 2015, 12:13:19 AM »
A successful car by the name of Speed Demon uses the 'hockey puck' style of front suspension.

Again, nothing new at the salt.

DW
White Goose Bar - Where LSR is a lifestyle
Alcohol - because no good story starts with a salad.

Don't be Karen, be Beth

Offline Jack Gifford

  • Hero Member
  • *****
  • Posts: 1568
Re: Near solid mounted front axle
« Reply #10 on: April 17, 2015, 12:36:02 AM »
Do most of the above comments pertain to lakes running? If so, can anyone say whether suspension (front and/or rear) would be of more/less importance on the pavement of ECTA and/or LTA?
M/T Pontiac hemi guru
F/BFL 1-mile Loring record 2020

Offline Milwaukee Midget

  • Global Moderator
  • Hero Member
  • ***
  • Posts: 6662
    • Milwaukee Midget Racing
Re: Near solid mounted front axle
« Reply #11 on: April 17, 2015, 12:45:28 AM »
Thanks for the input.  I think I'll give it a shot and build in some "friction shocks" in the locating arms.  If it gives me any concern during any runs it will be easy to change the stiffness or just swap out the rubber for some metal and voila... solid mount.



CAUTION - if you make a modification of that nature during a meet, run the car back to tech when you're done and make sure they're aware of it.
"Problems are almost always a sign of progress."  Harold Bettes
Well, I guess we're making a LOT of progress . . .  :roll:

Offline Mr. Schimstock

  • Full Member
  • ***
  • Posts: 132
Re: Near solid mounted front axle
« Reply #12 on: April 17, 2015, 08:27:49 AM »
A successful car by the name of Speed Demon uses the 'hockey puck' style of front suspension.

Again, nothing new at the salt.

DW

Figured it wasn't a new idea but had to ask.  Do you know if they run dampeners or just the pucks?
Sproing, crack, ouch!

Offline Mr. Schimstock

  • Full Member
  • ***
  • Posts: 132
Re: Near solid mounted front axle
« Reply #13 on: April 17, 2015, 08:29:17 AM »
Thanks for the input.  I think I'll give it a shot and build in some "friction shocks" in the locating arms.  If it gives me any concern during any runs it will be easy to change the stiffness or just swap out the rubber for some metal and voila... solid mount.



CAUTION - if you make a modification of that nature during a meet, run the car back to tech when you're done and make sure they're aware of it.

Yep... I'm thinking pretty much any changes would need to be run through Tech or at least give them notification to they can accept/acknowledge it..... which likely means running through tech again.
« Last Edit: April 17, 2015, 08:33:34 AM by Mr. Schimstock »
Sproing, crack, ouch!

Offline Mr. Schimstock

  • Full Member
  • ***
  • Posts: 132
Re: Near solid mounted front axle
« Reply #14 on: April 17, 2015, 08:32:16 AM »
Since we're on the subject of front axles, I assume a decent street rod/gasser front axle would hold up OK on the salt.  Most appear to be 2" OD 1/4 wall DOM.  Thought's/concerns on this using one?   
Sproing, crack, ouch!