Suspension Overhaul

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Galucha

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Figured I'd document my ongoing suspension/steering system overhaul here in case anyone is looking at doing something similar. So far I've done:

- 12.7:1 quick ratio steering box from Redhead

- new pitman arm, idler arm, rag joint, inner tie rods

- Baer adjustable outer tie rods for bump steer elimination

-  1 1/8" front sway bar

- StreetorTrack front coilover conversion

And I'm starting on the StreetorTrack rear 3-link suspension install this weekend. This should be considerably more involved than everything else listed above, so on one hand I'm somewhat intimidated by it, but on the other I'm really excited because this is the last suspension component I'm doing other than subframe connectors eventually.

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Galucha

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First things first, I removed the gas tank. The watts bar sits right in front of it, so rather than struggle getting that fitted in, I figured it would just be easier to take the tank out. My goal this weekend is to get everything removed in terms of shock absorbers, leaf springs, and rear axle. Not sure if I'll have fitment issues with my current exhaust, but I'm leaning towards yes, so will likely be removing it as well.

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thx for sharing, really curious to see how these goodies will fit and function.

Good luck with the install

 

Galucha

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Awesome package. Once you have that done you will need new sticky tires. Those tires will be the weak link to get the most out of the suspension.
Absolutely. I'm thinking I'll get some continental extreme contact DWS06 tires when I do. I have them on my other car and they perform really well for all seasons. Going to need to find some good wheels as well since my current ones are only 15x8.

 

Galucha

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Ok everything that needs to come off the car is out. Going to be taking tomorrow to start wire wheeling everything under here and prep for paint. Figured I might as well do that now since I don't know when I'll have the rear disassembled like this again. 

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Galucha

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Test fitting everything today. A couple of things I've noticed. 

1: the gas tank straps are going to have to to in before the watts bar as it looks like the bar sits right beneath them.

2: not going to be able to use the factory brake line support bracket as the 3rd link bar needs to go where it is. Going to have to do some creative brake line rerouting.

Next step is to take out the pinion snubber plate that's welded in the transmission tunnel with a spot weld drill, then I can actually bolt the watts bar and 3rd link bar to the frame.

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Galucha

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Ok both the watts bar and 3rd link bar are bolted to the frame rails now. The watts bar slid over the frame rails no problem, but I did have some difficulty getting the 3rd link bar fully seated - it was about 1/8" too narrow as you can see from the first pic. Emailed Shaun at StreetorTrack and he said that's typical as some cars will have wider or narrower set frame rails than others, and to use a dead blow hammer to get it lined up.

I will say the step bolts they gave you use to bolt everything up are pretty intuitive. They have you drill a 1/2" hole on the outboard side of your frame rails, and a 3/8" hole on the inboard side, so that the step bolt can effectively clamp both sides of the frame rails. Let's you torque them on pretty tight without worrying about warping anything.

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Galucha

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Ok fuel tank is back in! Took the opportunity to clean it up and get new gaskets and hardware. The fit against the watts link bar was very tight, but manageable. There's just barely enough room to fish the EVAP line between the tank and the frame. Now all that's left is welding the 3 brackets onto the rear end housing, and bolting it in. That's going to be next week's goal.

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Moving along great. I think they sort of blew you off on the frame rails having lots of variation. We stamped sub frames for Ford on several different vehicles. You do not get but a few thousandths of variation due to the parts coming from a hard die not fabricated.
The bolts you mentioned are standard socket heat shoulder screws like are used in dies. They are about equal to a grade 5 bolt. On factory bolts that go through a channel we welded in stamped brackets to prevent collapse. The shoulder bolts to work though.
I was reading through some of the SCCA rules the other night and saw they have approved the Swedish Steel Docal for use in roll cages. About time been around for over 15 years and is way better than 4140 or 4150. No weld issue with it.

 

Galucha

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Moving along great. I think they sort of blew you off on the frame rails having lots of variation. We stamped sub frames for Ford on several different vehicles. You do not get but a few thousandths of variation due to the parts coming from a hard die not fabricated.
The bolts you mentioned are standard socket heat shoulder screws like are used in dies. They are about equal to a grade 5 bolt. On factory bolts that go through a channel we welded in stamped brackets to prevent collapse. The shoulder bolts to work though.
I was reading through some of the SCCA rules the other night and saw they have approved the Swedish Steel Docal for use in roll cages. About time been around for over 15 years and is way better than 4140 or 4150. No weld issue with it.
Yeah I am a little disappointed in how hard it was to get the 3rd link bracket over the frame rails. I essentially had to use a jack to hold one side of the bracket flush with the frame rails, then use a dead blow mallet on the other side to get it to seat. So far that's been the only hitch though.

At this point all I'm waiting for is my rear end housing before final assembly. I marked it up for welding and dropped it off at my welding guy's shop on Monday, so hopefully getting it back before the end of this week.

 
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Galucha

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Are you upgrading your brakes? I will have a Wilwood front brake kit #140-13477 for sale soon. I probably have about 5,000 miles on it. This work great for street and AutoX, but I am now upgrading to a bigger kit so it can handle track time as well.

https://www.wilwood.com/BrakeKits/BrakeKitsProdFront?itemno=140-13477
I will be looking at upgrading brakes eventually, yes. But I am also wanting to get this car some track time as well, so going to go with something a bit bigger. I am thinking of this kit with matched rears since I know for a fact it will work with my granada spindles. Thanks for the heads up though!

 
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I will be looking at upgrading brakes eventually, yes. But I am also wanting to get this car some track time as well, so going to go with something a bit bigger. I am thinking of this kit with matched rears since I know for a fact it will work with my granada spindles. Thanks for the heads up though!
Wow. That's a nice kit with 14" disc. 

 

Galucha

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Ok finally moving again on this project. Got the housing back with the brackets welded on. The tabs for the third link are just tacked on right now so that I can verify their position and fitment before filling in the rest of the welds. Went ahead and test fitted everything to make sure there weren't any issues with binding - none that I can see and everything lined up perfectly with the exception of the passenger side exhaust pipe - I'm going to have to cut that off unfortunately and get it rerouted.

Next I'm going to be cutting the excess leaf spring pad area off so that the coils don't bind on them, and clean up/paint the housing.

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Galucha

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Used a sawzall to cut off the leaf spring perches and deburred with a flap disc.

The CPP brake lines fit pretty easily with no major reshaping. I think I will straighten out the driver's side tubing section, but it's nothing major compared to other brake line kits I've purchased.

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Galucha

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Ok everything is bolted in and now begins the long and arduous process of checking clearances, binding, and setting angles. Unfortunately my passenger side exhaust tube was binding so I had to cut it off at the muffler. Will have to get a new tube made and routed over the axle.

Using a magnetic digital angle finder here is a huge help. Basically just attaching it to stuff and them dropping the car then checking the readings on it.

A few things I'll be setting:

Ride height

Pinion angle (shooting for 1.5° to account for change under load)

Centering between the frame rails

Thrust angle (as good as I can get it)

Watts link angles

After test driving and getting an alignment then I can focus on more performance oriented tuning such as anti-squat, anti-dive, and cross weights.

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Galucha

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Pinion angle is set! Just took it for a cautious test drive, and everything seemed great. One note though, in the instructions, you are supposed to weld in a clearance box in the trunk. It has you doing this before you set pinion angle. I would recommend doing that AFTER setting pinion angle, as the bolt on top of the rear end housing gets torqued to 100ft lbs and is very difficult to get to from underneath the car.

Also noticed that my ride height in the rear was pretty low, even with the coilovers fully adjusted out. Right now the front of the car rides about 7/16" higher than the rear, so I will probably level it out. The distance from the ground to the bottom of the fender lip is 26 7/16" / 26" on the front / rear

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