Slam Specialty(UPDATE: 7-21-08)

Set it up likes its a 26" tall tire. Pretend like there was never a difference, and don't use the 25.5" dimension.

Okay, so that means I need to add that 1/2 inch to these measurements where applicable then, right?

BTW, What do you think about me now, Seth? Haha, do these numbers look good?

Seems like the upper bars may end up being a little short.

Look good seth?

I actually changed some values in comparison to my first posts values... I de-triangulated the uppers 3.75". If it works out right, the lower link bars will sit in the middle of the 2x3 x-member and the uppers will hook up at the x-member in front of it. Make sense? I'm wondering if this setup will work?

I cant seem to find out how to change the numbers around as if it were layed out, except the COG height... If I do that and raise the position of the frame link ends the whole IC and anti-squat goes gazooks on me!

EDIT: lol, I just noticed that you cant really see the numbers!

Wheelbase: 117.75"
Tire Diameter: 26"
COG Height: 18"

With my upper links triangulated and converging at the x-member on a side view, the 24" bars would look like 17.75" log. They would have a 4" spread from each other at the top view on the x-member. I figured 4" would be enough to get the wrench in there and whatnot... And the axle spread would be around 32". The upper bar would only point down by an inch through the run of its length.
Upper link height at axle: 16.75"
Upper link height at frame: 15.75"

At the axle, the lowers and uppers would be perpindicular to the ground or 180 degrees out from each other top to bottom.

As for the lowers, they would be parallel to the frame rails and be their 20" length. The spread as well on the axle and to the frame rails would be 32". I'm not quit sure if thats going to be the final number, but whatever it is, the uppers are gonna match...
Lower link height at
Lower link height at

With these numbers here, I get 42% anti squat, a 16in high roll center, 0degrees roll understeer, and the IC is 133in forward at a 9in. height.

Lol, and I may have to play with the numbers more to get it "perfect" but I kinda feel I may have struck gold on this one?! Lol!

...I hope I don't confuse anyone.

Sounds and looks good to me.

Technically you want a little bit of roll understeer. Its hard to get it 100% neutral, and after you build it you may end up with roll oversteer. So if you can calculate a little bit of understeer into the setup that would be a good idea. and 42% anti-squat is good. You should be able to accelerate without the back of the truck dropping much at all.

Saweet! I like to hear that from you, Seth!

I kinda wanted to also reply to the last PM you sent me, here. At the axle, the vertical spread is 7.5". Thats the most I can space it out without figuring a way to make more spread. And at the fram the vertical spread is 6.5".

So, the difference in spread vertically is 1". Should I strive for less then that or do you think thats gonna hurt my pinion angle still?

With the new numbers above, thats what I get and I would kinda guess that the IC is about at the bumper, and MAYBE a little forward and a little lower. I know atleast that it intersects at the frame though..

Other then that, I'll see if I can put some roll understeer in, but what would a good degree per foot be? Do you know what you set yours at?

Are you just happy now that you can hold an intelligent conversation with me? Hahaha!

Okay so I was a retard and Dev unknowingly helped me see something I forgot.

I got my link bars adjusted with the link ends out and all and I lengthened the lowers to a total of 23" eye to eye! The uppers are now 28" eye to eye.

I put in these new numbers, now, and I get 31% anti squat, a 15in high roll center which is only a 3 inch difference to the COG. That should'nt change much! I had to play with the numbers and I get 1 degree roll understeer per foot.

IC is located 144 inches and 8 inches in front of the axle. Boyo' it really sucked trying to get some roll understeer at the sacrifice of anti-squat!

SO, I don't want to spend anymore time on figditing with the numbers to get something minimally better. I think this is what I'm going to lock it in at!

Lol, I had to lower the lower bar frame end .3" and the upper 1.2" to get what I have. It sucks, lol!

Eh, well, Seth, would you say I should tweak anything else, or if it were you, would you be content with it?

I can provide a picture of the geometry if need be!

Throw up this picture!



Dev

If its cause I don't know any better, I'd say this here is tits!

It looks looks you've got a really good all around setup now. I would just run with that.

I don't calculate roll steer in a percentage, so I can't quite tell you a good number for that. I just go by inches, and I try to keep it under 1/16" per inch of travel. Sticking with that number, I have always had good results.