4400 IFS Rear Engine Ultra4 Build

[4runner DOA]

Right now thinking Currie, their whole 9" IFS setup ready to rock is like $5k and that's including 3rd member, where as spidertrax is more than that for just the IFS housing and inner stub shafts. I was reading up on Shannon Cambell's car and he only pulls 18" of front travel which seems really low to me, I'll have to talk to RCV and see what their max deflection is, but I'm guessing something else will limit it since you'd think with 30" arms you could easily pull more than 18" of 4WD travel.... Also, I figure I'll get the front diff and axles last probably, because I should be able to drive the car totally fine without the front drive components. So if I'm working faster than the money can flow, then I'll be able to start testing it in 2WD and just be waiting for the front diff and axles to bolt up which would be nice.

The rear engine makes packaging everything really nice, it'd be so hard to fit a 9" diff under/next to the engine if it was in the front. Now it's a straight shot from the atlas into the diff, and then the rear I can offset a lot so theoretically shouldn't get caught on rocks as much since it'll be closer to the tire, plus this will allow the rear driveshaft to be longer too. And now I can run the pair of 2.5x14 coilovers I have, and that will match up perfectly with a pair of 18" bypasses on the trailing arms and both will top out at ~25" of rear travel which is pretty good, and will be a cheaper setup than running IBPs like I was planning on before.

Apparently I need a better job.

 

[AssBurns]

I think the reason Shannon is only pulling 18” of travel is due to a tight turning radius. The more steering angle you have, the less travel you can get out of the outer joint. The outer joint from an RCV is like 45°, maybe a little more but not much. So if you have some really tight steering angles, you’ll really limit your travel to keep the CV angles low. For an U4 rig, it’s probably just as important to have tight steering as it is to have huge travel numbers.

 

[RPS1030]

I think the reason Shannon is only pulling 18” of travel is due to a tight turning radius. The more steering angle you have, the less travel you can get out of the putter joint. The outer joint from an RCV is like 45°, maybe a little more but not much. So if you have some really tight steering angles, you’ll really limit your travel to keep the CV angles low. For an U4 rig, it’s probably just as important to have tight steering as it is to have huge travel numbers.

Especially for every other series race outside of KOH. That’s a big reason for the number of IFS rigs IMO, racing/being competitive on all the short course events.

 

[snivilous]

Been messing around with different configurations and layouts and reading a lot. I think I'll need to start laying out the suspension since that will probably drive a lot of the layout. Need to learn more about weldments in Solidworks since I can't figure out how to consistently get tubes to intersect how I want, and also can't figure out how to convert the chassis into a single solid part to run FEA on it. But all this is part of the reason I converted the truck into CAD was to study up on how to draft a chassis!

 

[madtaco461]

Suppress everything you aren't using. File, Save as, Save assembly as part from drop down. Select "all components" before saving. See if that works.