LR shock angle

[rubbinsracin]

we ran an 01 shaw that is an underslung car and we are going to experiment with adjusting our LR shock angle for our playday this saturday the 23rd. we are going to move the chassis side of the shock further outboard to make it closer to upright at static. is there any type of drawback to doing this? what affects can it have on the handling of the car?

[MasterSbilt_Racer]

It can make the car stay flatter and not get up on the bars. I have seen it happen before.

[hpmaster]

I have experimented with about every LR shock angle you can think of and my findings are unless you are really using indexing and understand it on the left rear 14 degrees back at the top of shock and 14 degrees in at the top with shock behind axel is about as good as it gets. Just my honest opininon, a dozen weld on and couple clamp on top shock mounts later. In coming up with what you think is a benifit remember as the shock stands up more the closer it is to it's true weight rateing. So are you improving the handling with the angle or are you simply increasing the spring rate? Have fun. Now on the right rear, I plead the fifth ;)

[rubbinsracin]

so when you moved it closer to vertical did you see positive or negative results?

[WV_Race_Fan]

We have played with the angle of the LR shock in the past when we ran Swartz cars as Audie came up with the idea to add a shockmount on the outside of the LR frame rail. This was a 2000 4-link car updated to the newer swartz xtreme mounts (05-06 rear mounts). We ran that car for a long time, and after that our driver was able to get a ride driving for a different team which had rocket chassis and we experamented with it on their cars too. We used a weight clamp on the rear downward shock mount bar which the inboard shock mounts were connected to..

Anyway, when you adjust the angle of the shock it effects the spring rate and the amount of travel the shock will use... So before you make the changes you need to calculate where you are (spring rate wise) with the angle you have, and you can figure about what you need be when you stand it up.

You may also have to adjust the height of your rear shock mount on the birdcage to get the proper amount of shock travel that you need and/or its spacing left to right to get the angle you want.. The shock will travel more stood up V.S. more angle.

In a nut shell, we found that it loosened the back of the car up. It works well in a high bite/heavy situations, sweeping corner tracks, and when the track is a little rough. When the track is slick though and dusty, or glassy, it was more favorable to go back in.

We eventually set it up with 2 different shocks, and two different shock mounts both bolted to the birdcage to make it easier and faster to change in a hurry at the track. This was an alternative we found to adding bar angle and increasing rear steer to loosen the car. More so used, when we didn't want to change the current drive angles and rear steering angles themselves.

Later,

WV Race Fan

[rubbinsracin]

this makes me want to move it back to the original shock mount. i know that if i go from one mount to another its going to change wedge and wieghts and such. im going to have to rescale the car if i want to move them to know what it changes % wise huh?

[WV_Race_Fan]

If you simply unbolt the top of the shock and move it in or out it is going to affect alot more than percentages and wedge. You have spring rate, ride height, travel, 4 link angles, and J-bar angle that will all be effected in addition to what was previously mentioned.

To properly make this adjustment, you need to be on the scales. And by finding the rate of the spring as it is leaned in, and by keeping the spring rate close with it stood up (and you will more than likely have to use a different spring unless you aren't changing the angle much), it will allow you to retain your wedge numbers without really having to do much to the other 3 corners to get it back to where it was AND keep your ride heights consistant. Which will in turn keep your other angles and stuff consistant too.

Thats why knowing where you are with your spring rate v.s. degree of angle is so important. When we stood it up we went to a lighter spring and had to adjust the shock nut to "X" height to get the bite numbers where they needed to be and to keep the ride heights real close.

If you use the same spring and stand it up, the rate of that spring becomes stiffer than it was. And if you adjust the the shock nut back to the position it needs to be so that it kept your front and RR ride heights where they were origionally, check your wedge numbers on the scales, they will be different. And if you want to get it all right, you will then have to go through adjusting all 4 corners to get the bite you want and the ride heights right. Thats not something you want to find yourself doing at the racetrack!

Keeping the rate of the spring close after the change in angle will keep you from having to fool with all of that mess. Granted it's not going to be exact, but it will be very close. And after we fooled with making the move, spring change, and adjusting the shock nut at the track a few times. We just decided to get another LR shock, and have one set up to be ran inbored and the other set up to be ran stood up, and then just swap them out if we felt the need to make that drastic of a change. (back then though, we were running the cheaper twin tube shocks, so if you are running $600.00 double adjustable gas shocks I don't expect or suggest anyone to go buy another shock just to try this out).

Good luck with it if you decide to try it.

Later,

WV Race Fan