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Higgy9991
12-29-2020, 07:26 PM
I see a lot of cars with the 4 bar rods spaced in various directions. Either toward the center line or pointing outward, once upon a time we had a MBH car that had the rod on the outside of the bracket. Question is what are the effects, havent ever seen anyone really cover this. Lots of talk about indexing and rod angle but never down this rabbit hole so to speak. So anyone educate me on this one. Love to learn.

MasterSbilt_Racer
12-29-2020, 07:31 PM
I see a lot of cars with the 4 bar rods spaced in various directions. Either toward the center line or pointing outward, once upon a time we had a MBH car that had the rod on the outside of the bracket. Question is what are the effects, havent ever seen anyone really cover this. Lots of talk about indexing and rod angle but never down this rabbit hole so to speak. So anyone educate me on this one. Love to learn.

It's another way to adjust steer or index. Take rr top, for example. Say std location is straight ahead. Toe it in at ride height. That means it will effectively get longer when the rear moves left, as the car hikes. It will remove rear steer and make the rr spring effectively stiffer, because the cage rotates more.

fastford
12-30-2020, 08:43 AM
very good explanation masterSbilt .......

MasterSbilt_Racer
12-30-2020, 08:54 AM
You can play with the right more than the left. If you run lots of drop, it can be difficult to get it where it doesn't bind. That leaves no wiggle room for tweaking. The original poster also mentioned inboard vs outboard. The more inboard it is, the more effect the steering has. 1/4" of steer near the wheel is much more if you go inboard 8".

Higgy9991
12-30-2020, 10:29 AM
The main reason it was outboard is of the bracket was because there really wasn’t any room to be had inside the older Mastersbilt brackets. Does the angle at which the force is applied factor into this also. I remember having to go away from the rod out side the bracket because it was causing to much drive, the car had been originally setup for a open motor and we were on a 604 at the time. Again thank you guys for the knowledge, not many places to discuss these types of things, most everyone you meet at the track just want to tell you what to do, not so much why your doing it.

MasterSbilt_Racer
12-30-2020, 10:39 AM
It's not really the angle of the bar, but the point at which you are pushing on the chassis does matter. It's not as impactful as moving a pullbar, but it does matter.

Higgy9991
12-30-2020, 03:46 PM
Right the angle it is pushing on the chassis laterally left or right in relation to the linear push forward on the gas.

MasterSbilt_Racer
12-30-2020, 03:56 PM
Right the angle it is pushing on the chassis laterally left or right in relation to the linear push forward on the gas.

When you take all the 4 links, the tire loads, and the drive angle into account, you wind up with one force vector.

Moving any of those 4 links will have some effect and change that vector slightly. If you extend that vector out on paper, where it passes the cars center of gravity tells you how loose or tight the car is.

Higgy9991
12-30-2020, 05:11 PM
awesome info thanks MBR

dirtdobberrr
12-30-2020, 11:33 PM
I had not really considered this one, good thoughts guys.