Lift...WHY

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Feb 25, 2009 | 07:48 AM

#141

mastacox

Contributing Member

Joined: Dec 2003

Posts: 2,893

Likes: 2

From: Fort Worth, TX

Quote:

Originally Posted by saitotiktmdog

Normal force wont affect COF(assuming no deformation, however tires do deform so that makes things interesting but one can still measure the cof between tires and road experimentally).

I've been arguing the entire time that tires deform and so they cannot be described using linear friction! The deformation of the tire and material properties of the rubber make the apparent coefficient of friction a function rather than a constant.

Many things can change the frictional coefficient of the tire including air pressure, vertical force, horizontal force, etc. It all boils down to how the tire's tread is deforming under load, and the amount of shear stress in the rubber.

Here is a preview of an article written on the subject of friction of tire rubber: Tire Rubber Friction Article

The article's intorduction says this on the subject:

Quote:

Friction of rubber is complicated. Moreover, it is subject to factors such as temperature, vertical pressure, slip velocity, contact materials, etc. These factors make it hard to research on the frictional property of rubber.

Last edited by mastacox; Feb 25, 2009 at 08:01 AM.

Feb 25, 2009 | 06:05 PM

#142

Gerdo

Registered User

Joined: Nov 2005

Posts: 1,205

Likes: 1

From: SouthWest Littleton, Colorado

With a 95 4runner (2nd gen), as TC has said and proven, you run a 33" without a lift.

Mine is a 3rd gen. I lifted it for multipule reasons. Better approach, departure and break over angles. More clearence under the engine skid. And the big one, The old coils were worn out and was almost sitting on the bumpstops without anything in it. Why would I go back to stock when lifting it was cheaper. I did a 3" lift and love it. Even lifted I hit the front, back and middle.

I have wheeled with a guy that drives a stock 2nd gen and it has more clearence and more flex than my 2nd gen ever did. Now I'm ahead of him.

Mar 2, 2009 | 02:54 PM

#143

saitotiktmdog

Contributing Member

Joined: Nov 2007

Posts: 776

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From: Indiana

Quote:

Originally Posted by mastacox

The original argument was that increasing the normal force decreased the force of friction. (that is what you said and proported to prove by posting that gaph) THis is not true. I agree that tires do not behave like other compounds bucause rubber when hot becomes sticky, it also deforms. I never disagreed on that front except that you dont agree that the increased deformation increases the friction coeffecient. Which in and of itself contradicts your own argument.

Mar 3, 2009 | 07:44 AM

#144

muddpigg

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iTrader: (1)

Joined: Mar 2007

Posts: 4,374

Likes: 37

From: Enterprise, AL

Mastacox, Your wasting your time with these guys. They don't even understand the articles and formulas they quote. "You can lead a horse to water but you can make'm drink." In another time they'd argue the world is flat or that the sun revolves around the earth.

Thanks for your post and I look forward to seeing more of your post just on different topics.

Mar 3, 2009 | 08:51 AM

#145

Gerdo

Registered User

Joined: Nov 2005

Posts: 1,205

Likes: 1

From: SouthWest Littleton, Colorado

[QUOTE=muddpigg;51077087]In another time they'd argue the world is flat or that the sun revolves around the earth.
QUOTE]

I'm confused. What do you mean? The world is flat with the sun and everything revolving around it!

Mar 4, 2009 | 07:08 AM

#146

91FREERUNNER

Registered User

Joined: Oct 2008

Posts: 119

Likes: 0

Quote:

Originally Posted by almond_oxide_21

I lifted mine, to put 35's on. More clearance, also because as I'm sure some of the Older Yota drivers know, the alternator sits in a Sh***y spot so when doing some mudding it gets in there to fry it quite easily.
...some other factors.....
Fat girls can't jump.
I'm 18.
Looks sweet.

pretty much hit the nail on the head hahaha Im going to do bj spacers and new leafs in my 89 Im running 32x11.50s and they dont rub at all

Mar 5, 2009 | 02:46 PM

#147

Diesel_Freak

Registered User

Joined: Aug 2005

Posts: 420

Likes: 0

From: PDX, Oregon

Quote:

Originally Posted by Junkers88

I do agree that lifting a rig too high can be an issue. If all you plan to do is some hunting and fishing then a good set of 31" tires and a locker in the rear will get you a lot of places, learning how to pick a good line will get you farther.

I lifted mine with coils in the rear to eliminate 23 years of sag and get the spring packs off of the over loads. Basically to get the comfort factor back where it needs to be. I then lifted the front with ball joint spacers to level the rig ...

Yep, I wanted to run OME rear springs and that meant lifting the front to match but only 1.5in so not a lot of lift. I had to do something, these trucks ALWAYS sag in the rear untill you do something about it.

It drives a LITTLE different but I like the ride and the added belly clearence and A/D angles is nice too for the type of terrain I see but then my Marlin rear-bumoer and hitch deletion did about as much as the new springs did.

AS far as tires... Well didn't someone here run 35x10.50 SSR's with NO lift??? Just the usual bashing of the firewall etc. and as far as these trucks being LOW, I complete.y dissagree. Toyota trucks STOCK are a whole lot taller than anything in it's class. Look at a Jeep XJ if you want to see a LOW stock truck.

Cheers

Dave

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