Glen Strightiff/Chris Wilson C3 build

[SteveG]

I cut out the fill plug and inverted it to make room for the truss I plan to put there and also to allow for a higher oil fill level. I've found the ttb will eject oil from the vent if used continously at very high speeds (80-120mph). I use a catch tank on the vent so the oil drains back in when you slow down but I like the extra oil.

[SteveG]

More beam pics.

[SteveG]

For the pivots, we wanted to use an oversized uniball instead of the one that drops into the stock bearing cup. I took some 3" dia hole saw scraps, tack welded them over the pivot cup and used them to center the hole saw to bore out the stock cups to accpet the oversized uniball cups. The width of these larger cups is perfect.

[SteveG]

That's it for tonight!

[SteveG]

With the front end finally located, we designed and built the radius arm brackets. The radius arm heims will go on the outside of these brackets (below the frame) and in some of the pics you can see a long fe-fe which will have a tube that runs up to the cross member which runs over the tranny.

[SteveG]

Radius arm mount photos.

[SteveG]

So what is go fast front suspension without go faster steering? Next up is dual relay arm steering with ram assist and a 4 bolt, inside the frame Saginaw race box. We will use a 2:1 doubler on the steering column in addition to the speed up we get from the ratios on the relay arms. The packaging is tight.

At the upright, we are using the stock tie rod locations but with steel plate added to put the tie rod end bolts in double shear and of course the taper drilled out over sized with a machined 4130 steel insert put into the casting to keep the hole from ovaling out. All the steering heims are 7/8" with 5/8" bolts. Trophy truck sized stuff to reduce maintenance costs between races.

My thought on the location of the relay arms was that the inboard tie rod ends should be exactly in line with an imaginary line drawn through the middle of the suspension pivots. So we dropped a plum bob from the bearing center of the radius arm heim and another from the uniball in the TTB beam. Then drew a line on the floor that went through these two points and projected out under where the steering relay arms might be. But that only covers two dimensions X & Y. To pick up the third dimension, Z, we measured the height of each of the suspension pivots (radius arm and beam bearings), did some math on ratios and figured out how high from the floor the inner tie rod bearing should be to fall exactly on this imaginary line is space. The idea is that as the suspension moves, if the tie rod pivots on exactly the same plane then there should be no bump steer.

Anyway it's hard to get this exact. The result is that we needed the inner tie rod ends to be where they are shown in the photos and inboard swingers worked best for this. Note that the relay arms are asymetrical because we are using stock asymetrical beam pivots (which make for symetrical motion arcs as opposed to equal length beams which make asymetrical motion arcs since one beam must be ahead of the other.)

With the inner tie rod ends located we mocked up relay arms and tie rods and cycled everything (again). Over 20" of front travel we have about 1/4" of bump steer but almost all of it is at full droop and does not matter as much. We probably missed the imaginary ideal location by a little bit. Close enough.

So then we started fabricating real parts and swapping them in place of the mock up parts. For the relay arms, we used a 2.5" dia 4130 tube and milled out the inside on the lathe to accept a uniball. Then we machined a crush sleve to go between these. The relay arm then sits between two plates and is torqued to the max of the thought bolt. This design is simple, low maintenance and can handle high side loads.

[SteveG]

Photos.

[SteveG]

The engine is in the stock location using Autofab motor mounts, but we replaced the bushings with machined aluminum pucks. We have 20" front travel and 24" rear travel. Although the leafs are not in it yet and it may not droop out all the way with leafs installed. It did with our mock up leaf but once the full pack is installed and has some miles on it it may loose some arch. The frame rake you see is just a function of where we set the ride height. Right now it's just sitting on metal spacers. The rear spacer is too tall.

[SteveG]

Whew! That's all I have. Well, mostly. There is some text I need to go back and add after I figure out which photos is was supposed to go with.

Thanks again to Paul for consolidating all the photos and text into one file, to Glen Strightiff for such fantastic work and to Chris for sharing. I can't wait to see the rest of the build.

Take it away, Chris!

[baja-chris]

Ok, thanks guys, I'll toss up some new content and updates. I shrunk down the build photos to posting size. Got 550 of them so far. Obviously can't post them all. Here's a sneak peak.

[SteveG]

OK. Enough teasing, Chris. Let's see some more!

[PaulW]

BTW, That new motor is a Ford Racing stock Boss 351/427. Its aparently is still waiting for the Ford specified addons. intake, carb, headers, & front, etc.
nice
PW

[baja-chris]

Relay arm details. Uniballs inside a tube with a spacer between them. The spacer has a shoulder machined to land on the ball face so you can torque the pivot bolt and the relay arm swings freely.

[baja-chris]

Armor plating the TTB beam. It's upside down in these photos so we don't have to work upside down. Under the diff is 2 layers of .250 wall, 1/2" of steel.
The thin plates are chromoly plate, the .250 wall skid plate pieces are mild steel. In previous photos you saw how I moved the fill plug higher to clear the truss that is in these photos. Our steering is really packed in tight so I had to french the truss tube into the diff cover to clear the relay arm bolt.

[Copykat]

You guys are killing me. Now I have so many ideas rolling round in my head.

Need to collect more parts now.

[baja-chris]

More pics of the beam plating.

[baja-chris]

More beam pics.

[baja-chris]

Triple tube radius arms. We left a pocket open in case we needed to drop the shock end in there to keep the shocks under the hood. Turns out it was not needed so we will now plate over that open pocket.

[baja-chris]

Installation photos.