Roll Centers on G-Body

[steveshawjr]

heres some stats for yeh

Points Championship 1994, 1998, 2001, 2004
Mid Season Championship race winner 1994, 1995 Ridgetown 1996 1998 1999 2002 2007
Season champion race 1996, 1998, 2001, 2004, 2007, 2011
Most Checkerd Flags 1994 1995 1996 1997 1998 2001 2002 2004 2007 2010 2011
Fan Favourite 1998 2001 2002 2004 2007
total 311 wins... 100 a-main wins
updated Sept.11th 2011
Did not race in 2003, 2008, 2009

Steve Shaw Sr.

[stock car driver]

heres some stats for yeh

Points Championship 1994, 1998, 2001, 2004
Mid Season Championship race winner 1994, 1995 Ridgetown 1996 1998 1999 2002 2007
Season champion race 1996, 1998, 2001, 2004, 2007, 2011
Most Checkerd Flags 1994 1995 1996 1997 1998 2001 2002 2004 2007 2010 2011
Fan Favourite 1998 2001 2002 2004 2007
total 311 wins... 100 a-main wins
updated Sept.11th 2011
Did not race in 2003, 2008, 2009

Steve Shaw Sr.

Whats a fan favourite? Is that like coopitition that Larry McReynolds says?

So you set your car up on a shaker or pull down machine? None of those stats make sense Jimmy Johnson was the champion most of those years.

[steveshawjr]

you must have some timers lol you asked where we where winning at i put up our stats

Fan Favorite Driver award lol


32 years of this crap without any fancy equipment here dont even own a set of scales .... Never once did centers or anything like that ...

Steve Shaw Sr

[4bangerhotrod]

so have you raced at the same track every week for 20 yrs. thats what your stats are showing

[stock car driver]

you must have some timers lol you asked where we where winning at i put up our stats

I asked WHERE you were winning?

You didnt answer that. lol..

Still not sure now why your posting in this thread at all, now you claim to have never used scales or measured anything. But earlier in this thread you were saying we needed pull down machines, lol.

You must be buddys with Ego, he never answers anything directly and most of his posts are useless.

[steveshawjr]

now if you noticed he put steve shaw sr because my dad is the on that put them posts on .

now i never did claim i used a pull down rig for that matter you better go reread what is posted . i simply said that is what the big thing is now..

[stock car driver]

now if you noticed he put steve shaw sr because my dad is the on that put them posts on .

now i never did claim i used a pull down rig for that matter you better go reread what is posted . i simply said that is what the big thing is now..

Yeah on tv Nascar shows, lol...

[hogracer3d]

I wanna see a pic of JJ's wife, if there is one (which I doubt), but I'd accept a cancelled child support check.....

[stock car driver]

I wanna see a pic of JJ's wife, if there is one (which I doubt), but I'd accept a cancelled child support check.....

Man your a loser.

Join my fan page on face book and like the 1150 others on there youll know what Im up to most of the time, including some of the family vacations we take each year.

[sportmod224]

Hey Jeff, I have a couple questions I would like to ask you if you have time about the front spring set. Is there any chance we can talk on the phone instead of messaging back and forth on here? Thanks

[stock car driver]

Still nobody explaining how they get below ground when your last lines go to the tire centerline on the opposite side at ground level.

I guess Im the only one who manually lays out things to confirm my $300 dollar program is correct.

[petermanbuilt]

Alright, I guess I will set this straight for Jeff, since no one else will.

When plotting roll centers, project a line through the control arm pivot and the ball joint pivot for each control arm.

The intersection of the lines through the left upper and left lower defines the instant center for the left side suspension.

A line is then projected from this instant center to the center of the left tire contact patch. I will call this line the "left side swing arm" for future reference.

Repeat the 2 above steps for the right side.

Finally, the Moment center is determined by the intersection of the left and right side "swing arms"

Where you are WRONG Jeff is in saying that "swing arm" line goes to the opposite side. The left instant center will always project through the left side contact patch, and the right instant center always projects through the right side contact patch.

Anytime that the instant center lies outside of the tires, the moment center will be "underground" for lack of a better term.

See this link as I have drawn it out. I exaggerated the angles to make it fit on a sheet of paper.
If that is not enough I will keep proving you wrong with multiple vehicle dynamics textbooks.

http://s823.photobucket.com/albums/z...elowground.jpg

Nathan Peterman
Penn State Mechanical Engineering Alumni

Still nobody explaining how they get below ground when your last lines go to the tire centerline on the opposite side at ground level.

I guess Im the only one who manually lays out things to confirm my $300 dollar program is correct.

[stock car driver]

Your drawing is based on the upper a arm angle forcing the instant center outside the tire centerlines, is that the deciding factor that changes your next point from the opposite tire to the cl of the tire on that same side?

Maybe thats correct I dont know thats why Ive been asking.

[stock car driver]

Where you are WRONG Jeff is in saying that "swing arm" line goes to the opposite side. The left instant center will always project through the left side contact patch, and the right instant center always projects through the right side contact patch.


If that is not enough I will keep proving you wrong with multiple vehicle dynamics textbooks.

http://s823.photobucket.com/albums/z...elowground.jpg

Nathan Peterman
Penn State Mechanical Engineering Alumni

Go ahead and keep proving me wrong if thats what makes you feel good about yourself. I asked this question how many times?? obviously I dont know the answer or I wouldnt be asking, I dont see how ASKING for explanation can be proven wrong but whatever floats your boat...

I read your post again and I see you say ALWAYS, I look forward to many more posts from you backing up your ALWAYS since I can post many that say it isnt ALWAYS as you have said. I believe your ALWAYS only pertains to when the instant center is OUTSIDE the wheel base.

[stock car driver]

http://i642.photobucket.com/albums/u...b/101_0113.jpg

So this book is wrong?

[petermanbuilt]

Your drawing is based on the upper a arm angle forcing the instant center outside the tire centerlines, is that the deciding factor that changes your next point from the opposite tire to the cl of the tire on that same side?

Maybe thats correct I dont know thats why Ive been asking.

Yes the instant should should project to the contact patch of the tire on the same side!

A metric is suspension is considered an independent type suspension, simply meaning that the actions of one wheel do not have a direct effect on the other. Because of this, the IC of the left does not correlate to right side contact patch.

In contrast, when one side of a solid axle suspension hits a bump, the opposite side is forced the opposite direction because the two wheels are connected by essentially a beam.

Check out Chapter 17 of "Race Car Vehicle Dynamics" by the Millikens. It lays it all out. This book is widely considered a "bible" for vehicle dynamics as the authors spent their entire life researching the subject before writing.

I don't want to get into a pissing match, just trying to keep you from telling everyone that they are wrong when in fact, your the one that incorrect.

[stockcar5]

peters pic of right for below ground roll centers and jeff yours is correct for the ic being inside the tire contact patch.

saying the ic is always within the wheelbase is as wrong as saying there is no way the roll center can be below ground with lowers level.

[petermanbuilt]

http://i642.photobucket.com/albums/u...b/101_0113.jpg

So this book is wrong?

Nope, that drawing is correct. The instant center on the left is drawn to the left side contact patch and visa versa

I added some color to the picture you posted to show that they too are using what i said above

http://s823.photobucket.com/albums/z...ment%20Center/

[stock car driver]

Nope, that drawing is correct. The instant center on the left is drawn to the left side contact patch and visa versa

I added some color to the picture you posted to show that they too are using what i said above

http://s823.photobucket.com/albums/z...ment%20Center/

Step 10 in your color pic is the instant center going to the opposite tires centerline.. Thats what Ive said all along. I see what your saying that the instant center of the left suspension which is actaully located on the right comes back to the left tires centerline. That is the tire opposite the instant center point isnt it? lol.. just like Ive said all along.

What youve explained which nobody else explained was what to do when the instant center is outside the tire, your drawing makes sense. thanks.

It does appear you want some sort of pissing match.



Stockcar5, you might as well shut up, Ive asked you to explain how you get below ground repeatedly you had nothing to offer.. This guy explained it. Scroll back I asked point blank before how the roll center was plotted when the instant center is outside the tire.. YOU didnt know your just put the number in your program, lol..

[stockcar5]

if i explained it to you you'd piss and moan anyway like always. i drew it out back in 2003 then bought a program. you'd be retarded to try and draw one out now if you own software.
i figured we were long past explanation when you clowns started comparing stats and asking each other for pics of your wives...lol