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View Full Version : New rules promt another shock placement thread



Mod77L
01-07-2011, 02:42 PM
Our 2011 B-mod rules changed to require a 3-link or leafs. I'm going to revert my 4-bar to the 3-link.

The rules specify that the springs and shocks must be mounted in the same place, side-to-side. (ie., if the LR shock is in front, the RR shock must also be in front.)
Also, L & R link angles must be within 5* of each other, and visually parallel side-to-side.
Both sides must be mounted the same distance below the axle tube.

Both tracks I run are 1/3 mile. The Friday track is at 8* banking, and the Saturday track is about 16-18*.

At this point, I'm not worried about changing springs or shocks. I'll worry about that when I can evaluate the setup properly at the track.


Would you run coil-overs? Eliminators?
On swingarm, in front, or behind?
Its a bit more work and cost, but springs on top of the housing?
(Remember, L & R sides must have the same mounting locations)
I would have used the info provided in other threads, but most, if not all of them, put the shocks and springs in different places on each side.


Is one location better for the flatter track, and another better for the higher banks?
Should I be concerned with changing their locations between heavy/tacky and slick conditions?

Or, should I just pick a position, and spring/shock the car to run them there?

We can run a straight bar or j-bar, but it must be at least 19" long. I'm not sure about what I'm going to use because of possible interference problems depending on where the springs and shocks are mounted. If it matters, as a 4-bar, the car preferred a very low, left roll center on an average track (Features are usually about 1/2 way between tacky and slick).

EFR Motorsports llc
01-11-2011, 11:45 AM
Put them in front otherwise you will never get any LR drive. You will probably have to go softer RR spring and start with the j bar about 1/2" lower than you had before.

dirttrackrocker
01-11-2011, 01:21 PM
I really don't understand this rule... Why?? Makes no sense to me...

loneranger22
01-11-2011, 02:21 PM
These are the 2011 WISSOTA MW (B) mod rules. They make NO sense to anyone, but thats WISSOTA for you.

racin6mod
01-11-2011, 10:36 PM
The B-mod class has started to get better car counts than the A-mod class at a lot of tracks across the country.might be part of the reason.

Mod77L
01-12-2011, 12:12 AM
Put them in front otherwise you will never get any LR drive. You will probably have to go softer RR spring and start with the j bar about 1/2" lower than you had before.

Most of the advice given about 3-links agrees with the spring in front on the LR. Most setups also have the spring behind on the RR. How will moving it to the front effect entry and/or exit (using LR forward, RR behind as a baseline)?

EFR Motorsports llc
01-13-2011, 10:05 AM
It will varry quite a bit depending on your driving style, mostly corner entry if you are on the gas at entry it will tighten entry. if you dump the gas right at or before your entry it will have a loose feel. This is why you will have to play with RR spring rate and j-bar rake, I think that will be your two main things to work on. What kind of pull bar are you on that spring rate will also have a more critical role in this situation.

Mod77L
01-13-2011, 02:34 PM
We are allowed to run a poly-bushed (example (http://chubeck.com/new/images/bushings.jpg)) end on one end of the pull bar. No other springs, bushings, or damper shock. But, I'm not sure if the small amount of travel is worth the cost ($50/ea). I'll probably just make it solid.

I haven't decided whether to stay with my current length (32") or go to a shorter one.

EFR Motorsports llc
01-13-2011, 08:15 PM
You don't want to use that it will bind up or break the stud when the car gets any rear steer. If you cant use a rubber bushing pull bar like a regular a mod just go to the solid one. Do they have a min or max bar length for the lower bars?

Mod77L
01-14-2011, 09:44 AM
No max, 15" min. There can be a max of 2" difference in length between the two. I imagine its meant to allow for lead/trail.