Suspension Travel limits??

[Grimm]

So if suspension travel is the key to desert racing as said in another thread, what are the limiting factors?
Since we are 4x4's is it the front and rear drive shaft lengths. Are there special driveshafts that can increase travel potential with like slip yoke or something?
What would you think is a good wheel travel for C3 front and rear? We are shooting for 12-14 front and hopefully around 18 +- in the rear. Are these #'s realistic or are we just dreaming with solid axles, coilover in front and leaf in rear.
I don't want to set my goals to high and then be crushed.
Thanks

[3amigo]

The front travel #'s you give are very doable, especially if you use a HP front axle. U-joint angles are going to be a limiting factor. A stock single joint is only going to want to run constantly at about 15 degrees. I would recomend going with a double cardigan or CV style joint on the case output and then rotate the pinion on your axle to point at the output of the t-case. This will give you the best angles on the shaft and allow for the most travel. Slip yolk travel depends on how the axle moves in relation to the t-case. On a ford with radius arms the slip travel is usually not a problem. The rear will probably need a longer slip shaft. It is better to go a little on the safe side with slip. If you pull the shaft apart on on droop you get a very nasty surprise when the shaft digs into the ground. If you bottom out the slip it usually brakes the t-case and the shaft. I would recomend Jesse at High angle drivelines. He specializes in the rock crawling world and makes really nice heavy duty shafts.

[straightaxle]

You won't be able to ge those numbers with stock driveshafts and solid axles, but you can get close. There are some trick driveshafts, special u-joints, and moving the t case around that will help you to get that last 1 or 2 inches. Just remember those trick parts are $$$$ and have to be replaced on a regular basis and you have to have spares.

[chupakabras]

we did this to our ttb slip yoke, grind the inside area to get more angle, when the suspension drops actually hits there, so, we solve our problem by doing that and also we need it to cut about 1/8 of an inch on the right shaft, the one that goes into the slip yoke because it was hitting there too.

the photos are from therangerstation.com

http://www.supermotors.net/getfile/515410/fullsize/bindspot.jpg
http://www.supermotors.net/getfile/515411/fullsize/compare.jpg
http://www.supermotors.net/getfile/515412/fullsize/yoke2.jpg

[jonnyslick]

what are realistic numbers for a TTB bronco front and rear?

[Mr. Pickle]

On a similar note: what are some realistic numbers for a straight f/r axle Blazer? (using leafs)

[Blanco]

what are realistic numbers for a TTB bronco front and rear?

Thats a Good queston that has me wondering what more I can get out of mine?

I'm currently @ 15 & 1/4 inches with my TTB.

[jonnyslick]

Thats a Good queston that has me wondering what more I can get out of mine?

I'm currently @ 15 & 1/4 inches with my TTB.

i was thinking around 15 or 16" up front and 18" in the back would be realistic ... but i'd like to hear numbers from guys really doing it. that's great you're getting 15" out of it, really that's not too shabby at all! :D

[tsm1mt]

IMO, driveshafts are our limiting factors, due to wheelbase and 4x4 requirements.

The 15" front / 18" rear seems realistic to me.

Assuming the front driveshaft is the shorter 'shaft, I'd look at clocking the front output down as much as I can get away with. You'll want to get to where the front driveshaft actually slopes UP from the t'case to the pinion at full bump. That'll get you the most.

Do some trig and you'll come up with max travel numbers operating the joint(s) at ~25deg with the driveshaft length you have to work with.

I get 30-deg out of my 2 U-joints (no CV) but had to grind the output shaft of the t'case down because the body of the U-joint was hitting the output shaft at full droop.

At full bump I have problems with the driveshaft hitting the transmission pan, so I had to adjust where "full bump" is. If I rotated the front output down, I'd gain a bunch of travel - a few more droop inches, and a little more bump, too.

In the back, just keep that driveshaft as long as you can, and set the air bumps up so it almost bottoms against the frame.

I'm currently running solid axles f/r and leaf springs, SOA.