View Full Version : Panhard bar, needs to be horizontal?


OldeSkool
10-12-2005, 02:25 AM
http://www.jegs.com/webapp/wcs/stores/servlet/CategoryDisplay?catalogId=10002&storeId=10001&categoryId=24299&parentCategoryId=11177&langId=-1

How important is it that the panhard bar be level to the axle?

lt1fbody355
10-12-2005, 07:04 AM
It shouldn't be even close to being level. Just measure from the body to the tire on both sides adj. accordingly untill both sides measure the same. A panhard bar is really only important on lowered cars with big tires, but some will say otherwise.

will

Sam Strano
10-12-2005, 12:13 PM
I think I've officially heard it all now!

The PHB should be pretty level because the more on an angle it is the more of an arc is travels through as the body rolls or the suspension compresses, and that in turn pulls or pushes the axle to one side or the other, and that's changing your track width.

Also a PHB is a part that must be there as it's the only thing that locates the axle relative to the body laterally. I think maybe lt1fbody355 meant to say that aftermarket PHB's are really only important on lowered cars with big tires.... I hope.

I'd state that better PHB's are a definite help to handling and stability and can benefit a stock height car that sees some cornering action as well.

OldeSkool
10-12-2005, 01:14 PM
It certainly makes sense to me. I know mine isnt level and I think it may contribute to why the back of my car feels like pooh over bumps, i was just wondering why more people dont seem to correct this and i thought either my car was odd and everyone else' phb is level or maybe the length of the bar is sufficient to compensate for a small amount of slant or maybe most folks just dont care.

DONAIMIAN
10-12-2005, 03:41 PM
I think jegs says that its ok to have that thing just bolted in, however it SHOULD be welded in. Its other kits out there, but im late to class and post more when I get back.

lt1fbody355
10-12-2005, 06:57 PM
I think maybe lt1fbody355 meant to say that aftermarket PHB's are really only important on lowered cars with big tires.... I hope.

.


Yeah I meant to say adjustable phb. good catch :emb:

Major_Lee_Slow
10-12-2005, 08:07 PM
Hey Sam, take a look at this and tell me what you think.

On our cars, with an Eibach Pro kit the frame side of the PHR is 1.717 inches on my SS. The following is geometric results in roll:

Outer wheel (LH) roll centre
camber caster pinion scrub tramp toein offset height
0.00 roll 0.000 1.958 -0.042 0.000 0.000 0.000 0.000 10.675
0.50 roll 0.000 1.934 -0.066 0.006 -0.013 0.009 -0.014 10.771
1.00 roll 0.000 1.910 -0.090 0.012 -0.028 0.018 -0.028 10.867
1.50 roll 0.000 1.886 -0.114 0.017 -0.047 0.027 -0.042 10.962
2.00 roll 0.000 1.862 -0.138 0.023 -0.068 0.037 -0.057 11.057
2.50 roll 0.000 1.838 -0.162 0.028 -0.091 0.047 -0.072 11.152
3.00 roll 0.000 1.814 -0.186 0.034 -0.118 0.058 -0.087 11.247
3.50 roll 0.000 1.791 -0.209 0.039 -0.147 0.069 -0.102 11.341
4.00 roll 0.000 1.767 -0.233 0.044 -0.179 0.081 -0.118 11.435

Inner wheel (RH) roll centre
camber caster pinion scrub tramp toein offset height
0.00 roll 0.000 1.958 -0.042 0.000 0.000 0.000 0.000 10.675
0.50 roll 0.000 1.934 -0.066 -0.006 0.008 -0.009 -0.014 10.771
1.00 roll 0.000 1.910 -0.090 -0.012 0.014 -0.018 -0.028 10.867
1.50 roll 0.000 1.886 -0.114 -0.017 0.019 -0.027 -0.042 10.962
2.00 roll 0.000 1.862 -0.138 -0.023 0.022 -0.037 -0.057 11.057
2.50 roll 0.000 1.838 -0.162 -0.028 0.023 -0.047 -0.072 11.152
3.00 roll 0.000 1.814 -0.186 -0.034 0.023 -0.058 -0.087 11.247
3.50 roll 0.000 1.791 -0.209 -0.039 0.020 -0.069 -0.102 11.341
4.00 roll 0.000 1.767 -0.233 -0.044 0.016 -0.081 -0.118 11.435


Now with the axle side lowered so that the bar is level:

Outer wheel (LH) roll centre
camber caster pinion scrub tramp toein offset height
0.00 roll 0.000 1.958 -0.042 0.000 0.000 0.000 0.000 9.813
0.50 roll 0.000 1.934 -0.066 0.007 -0.010 0.006 -0.011 9.908
1.00 roll 0.000 1.910 -0.090 0.014 -0.022 0.012 -0.023 10.004
1.50 roll 0.000 1.885 -0.115 0.020 -0.037 0.019 -0.035 10.099
2.00 roll 0.000 1.861 -0.139 0.027 -0.054 0.026 -0.047 10.195
2.50 roll 0.000 1.837 -0.163 0.033 -0.075 0.034 -0.060 10.290
3.00 roll 0.000 1.813 -0.187 0.039 -0.098 0.041 -0.072 10.385
3.50 roll 0.000 1.789 -0.211 0.045 -0.123 0.050 -0.086 10.479
4.00 roll 0.000 1.765 -0.235 0.051 -0.152 0.058 -0.099 10.573

Inner wheel (RH) roll centre
camber caster pinion scrub tramp toein offset height
0.00 roll 0.000 1.958 -0.042 0.000 0.000 0.000 0.000 9.813
0.50 roll 0.000 1.934 -0.066 -0.007 0.005 -0.006 -0.011 9.908
1.00 roll 0.000 1.910 -0.090 -0.014 0.008 -0.012 -0.023 10.004
1.50 roll 0.000 1.885 -0.115 -0.020 0.009 -0.019 -0.035 10.099
2.00 roll 0.000 1.861 -0.139 -0.027 0.009 -0.026 -0.047 10.195
2.50 roll 0.000 1.837 -0.163 -0.033 0.007 -0.034 -0.060 10.290
3.00 roll 0.000 1.813 -0.187 -0.039 0.003 -0.041 -0.072 10.385
3.50 roll 0.000 1.789 -0.211 -0.046 -0.003 -0.050 -0.086 10.479
4.00 roll 0.000 1.765 -0.235 -0.052 -0.010 -0.058 -0.099 10.573


It appears to me that the big gains are in the toe change. There is less toe in with a level bar. Is this a desirable or un desirable trait?

The scrub seems to be increased by a little less than 0.01 inches and teh tramp is drecreased by about 0.03 inches all at 4 degrees of roll. What's your thoughts on this?

2002_Z28_Six_Speed
10-14-2005, 11:41 AM
Just a thought...

I just put 2000 Corvette wheels and SS springs/shocks on my 2002 Z28. 17's and 18's. The rear wheels are 275 40 18's.

When I had the car lined up, the guy told me my axle was slightly "twisted." The left side was 1/16'th of an inch in front of the right side.

Do you think that because the car is lowered and has larger tires the panhard bar is out of spec for this configuration?

I know a lot of people have done things similar to this on LS1 Tech.

Any thoughts?

John_D.
10-14-2005, 12:06 PM
Panhard shouldn't affect rear toe or put one wheel ahead of the other. LCA's could do that though. (and could fix it too...)