Thanks Kyle, that sounds like exactly what I'm looking for. Hopefully I'll be calling on you around the first of Feb for a kit. 
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Northwest Fab 60 highsteer arm
- Thread starter jagermiester
- Start date
jekbrown said:any1 have any diagrams or anything that can explain the above. CS knows his shizzle, so I assume he's correct, but I'm having a tough time figuring out how tie rod length changes anything...From what I remember of my WFO arm, it was machined so the TRE mounting surface is pretty much parrallel to the ground... seems like the tie rods length wouldn't mean much.
j
Well, I was a little loose on my "tie rod length" statement. The length of the tie rod doesn't matter, it's relation of where it ties into the steering knuckle relative to the balljoint/kingpin axis. So, the tie rod can be any length that keeps it in line with the correct angle to get the proper ackerman angle. Then it has to clear the differential cover. If you look at a Ford HP60 the tie rod bends out around the differential cover so the tie rod can be close enough to the kingpins to get inside of the wheel far enough for proper (well, close anyway) ackerman angle.
It's a lot easier to get proper ackerman angle with behind-the-axle steering because the further the tie rod mounting point is from the wheel the "more ackerman" it has.
Anyway, ackerman angle is trying to calculate the way to get a vehicle to turn without causing tire scrub. As you know, your two front tires follow different diameter circles. The inner tire needs to "kick in" towards the center of the corner you're turning in order to not fight the other tire (scrub) when going around the corner. Well, with steering in front of the axle, to get proper ackerman angle, you pretty much need to have that tie rod mounting point right next to the brake rotor as close to the outer edge of the wheel as possible (so it doesn't rub the differential cover).
Well, with 15" wheels with 4" of backspacing on stock 1/2 ton axles, you can't move it over that far or your tire will rub the TRE. Sky's arms are so close with 1/2 ton stuff that a squishy tire would probably rub if deflected. Behind the axle steering you actually pull the TRE mounting point in towards the center of the vehicle. This is nice, especially if you want to run double beadlocks. "eyeballing" NWF's and Sky's double ended steering arms, they look pretty much spot on for a 110" wheelbase rig.
You don't really notice ackerman angle unless you're turning at or near full lock. Normal driving around town, say 10° or so of turning, doesn't really involve ackerman angle. It's not until you're trying to turn a tight circle that it is important. One of the ways to see how much ackerman affects a vehicle is to take a Jeep with waggy axles and put the tie rod on the front two holes on the knuckles and the draglink on the rear hole. It'll go from a decent turning rig to one that needs a football field.
jagermiester
1/2 ton status
Thanks for all the information guys. NWF I hope to be ordering an arm, tierod and draglink from you here soon. I also apprecdiate the return email answering all my questions.
CyberSniper said:
Thanks much CS, the above comment really turned the light-bulbs on for me.
I run the WFO arms with behind-the-diff tie rod placement... I guess its good to know (after the fact!) that that is a good thing. 
j
Yeah, I'm kind of torn between NWF's and Poison Spyder Customs'. PSC's can be adjusted (kind of) by selecting the hole you put the tie rod in. But, NWF's look like they're pretty much spot on and they are pulled in away from the tire. PSC's being a straight arm, you can adjust your ackerman angle a bit but the TRE I bet gets real close to the tire.
