STi brakes, the brute force way!

[sperry]

Wow, as soon as I complain about backordered parts... they get mailed! It looks like Jegs has sent my reamer... though the tracking info doesn't pull up anything yet. They certainly charged my credit card for the part though.

Hopefully I'll have this thing by the end of the week so I can get this car back on the road over the weekend!

[Pegdrgr]

Excellent!

[sperry]

Well, I know when I'm beat. And taking 4 hours and 2 saw blades to make 5 cuts is when I'm beat. I simply don't have the right sort of saw to handle 3"x0.5" steel. I've got a 12" miter saw, but I really need a horzontal band saw for cutting this stuff accurately.

Here's what about 4 hours of spark throwing, saw melting, work accomplished before I gave up:





You'll notice that's not quite the same as my "final" drawing above... I did make one more wood mock-up and didn't like the clearance to the LCA or how much negative camber the adapter was generating. So here's the new "final" drawing... who know if it's actually "final" this time.



I ended up angling the cuts on the top piece for two reasons... better clearance to the lower control arm, plus thicker side walls around the ball-joint taper so I can move the hole closer to the centerline of the car and add a little camber.

So, now I just need to find a machine shop willing to make some cuts for me... or pick up one of these:



It's only $200, which considering shop labor is around $75/hr isn't all that expensive since it'll pay for itself relatively quickly... I just don't have room in the garage for a big ass saw.

I did accomplish at least one thing over the weekend. I welded some 1/4" steel tube to some 3/4" black pipe and then sectioned them to the proper 22mm to make some ABS sensor standoffs. That should allow the SVX ABS sensors to line up properly with the tone wheel on the axle.



I'll get some pictures of them installed once the paint dries.

[Cam]

Don't forget that if you heat the steel up too much it will lose it's temper and become weaker. Red hot is bad...

Does that horizontal band saw have an auto shut-off when it bottoms out?

[lhopp77]

Originally Posted by Cam

Don't forget that if you heat the steel up too much it will lose it's temper and become weaker. Red hot is bad...

Does that horizontal band saw have an auto shut-off when it bottoms out?

Horizontal band saws cut pretty slow, so don't build up much heat. Some have coolant hoses, but it's not usually needed. Or you can actually pour water or coolant on the cut area by hand to keep heat down.

My horizontal saw does not have a auto shutoff when it cuts through, but there is space for the blade and it does not hit anything when finished.

Lee

[sperry]

Originally Posted by Cam

Don't forget that if you heat the steel up too much it will lose it's temper and become weaker. Red hot is bad...

Does that horizontal band saw have an auto shut-off when it bottoms out?

No way the metal was getting anywhere near that hot. My saw blade was glazing over and shredding long before the steel was getting red-hot.

[sperry]

Here's the ABS stand-off adapter installed.



You know... something I just thought of... I hope those sensors don't require grounding to the spindle, 'cause I painted that standoff with hi-temp paint. I may be scraping the ends clean to allow it to ground properly.

[sperry]

I dropped off my blueprints and a slab of flat bar at the machine shop. They'll be cutting me a pair of wedges by 3:30 today. Then tonight, I'll machine the holes and BJ taper myself and hopefully have the car on the ground sometime today.

*finger's crossed*

sicksubie, I'm not planning on making two sets yet at this point. I want to make sure the first ones fit properly and that the car can be aligned properly. If I end up needing to make another set, I'll go ahead and make 4 of them then, otherwise, I'm going to see what it'll take to have my friend's shop fabricate them as a for-sale item at his store.

[Cam]

With the problems of brake dust, road grime, and oil leaks in the area of that sensor, I hope for design sake it is grounded through a jumper in the wire bundle, or a similar design. Someone on here probably could check their wiring diagram though.

[sperry]

Originally Posted by Cam

With the problems of brake dust, road grime, and oil leaks in the area of that sensor, I hope for design sake it is grounded through a jumper in the wire bundle, or a similar design. Someone on here probably could check their wiring diagram though.

Considering I've had to repair the ABS sensor on my racecar before and it had two wires, I'd assume the SVX is the same.

Plus, I think just in terms of the way a hall-effect sensor works, you would have to run two wires because there really isn't a "ground" per-se. It's an inducer so you would need two wires across which the current is induced... it would be complicated to read that current if one of the "wires" were the chassis ground.

In other news, I didn't get home from work until well after 8pm last night, so I didn't get around to finishing up those BJ adapters. Hopefully tonight.

[sperry]

Well, another few hours spent and I've finally got some ball-joint adapters!





And a quick test fit looks pretty spot on.



I also tossed my endlinks in my tow-hitch mounted brake and put an angle on 'em.





The only sucky thing, spring steel takes a crapload of force to bend... I bent the hinge on my brake when bending the links. But a new hinge is a lot cheaper than fabricating new shorter endlinks.

I am a little concerned that having the bend in the link will result in softer turn-in... or worse, a hard bump might bend the link even further. But the alternative is building links from scratch, which is what I'll end up doing if these suck or fail.

Here's the clearance gained from the bent links, much better than 2mm:



After these pictures were taken, I primed and painted the BJ adapters. I'm gonna try to install them today on my lunch break and perhaps even get the car aligned this afternoon if everything goes together quickly enough and there are no issues once the car is on the ground.

Right now I'm expecting about half a degree more negative camber with these adapters over stock, and maybe half an inch lower ride height... but I'm really unsure about the ride height changes, since I haven't been able to put the weight of the car on any of the wood test adapters. If this thing rubs the tires, I may not have any options aside from adjustable coilovers.

[Pegdrgr]

Looks like it really came together nicely.

You could TIG the two pieces together nicely, although I doubt it would add much function, just be darn pretty!

[sperry]

Originally Posted by Pegdrgr

Looks like it really came together nicely.

You could TIG the two pieces together nicely, although I doubt it would add much function, just be darn pretty!

I thought about welding the whole thing, but decided it would be prettier with just a few spot welds with my MIG to hold things in place while I was boring the BJ taper. As you mentioned, the welding isn't required structurally... the clamping force of the ball-joint holds everything together.

So anyway, here are the adapters all painted up:



I used a little make-a-gasket to hold the washers in place during installation:



The washers are there to ensure the adapter seats to the control arm the same way the OEM ball-joints seat.

I finished the install over lunch, but had to wait until after work to finish up with bleeding the brakes, topping off the front diff oil, and swapping the rear wheels. Then I took it for a spin.

The car feels solid, the steering feels better than it used to with the over-sized low-offset wheels... I'm hoping the scrub radius has been reduced even though the wheels are sort of popping out of the wells now. But I'm not sure I want to make any guesses at the handling of the car until after I get it aligned.

The bad news is that the ABS light came on after driving for a bit. My guess is my standoffs are too thick. I intentionally erred on the side of too long... so I'll have to pull them off and get out the grinder. I know there's a few mm of space in there yet.

Also, at full lock my front tires rub. Not sure where, but I'd guess it's the fender. This is likely just an issue because of the spacers I'm running to clear the brakes. It's pretty minor... just pulling off the fender guard may fix it... otherwise 10 minutes with a fender roller will do the job.

The worst news though is that the brakes aren't as awesome as I was hoping. The pedal is still pretty soft. The braking feels markedly better, but it's nowhere near as solid as my race car. I'm betting it's a combo of the old rear brakes, the SVX's master cylinder, and not having a brace on the master cylinder. But while the pedal feel isn't fantastic, the car should now be way more track-ready to handle repeated hard braking.

Here are some shots of the car on the ground. The STi ball joints look like they squared up just right with the weight of the car on them:





The ride height looks just a little lower than stock, though I don't have a good before picture to really compare against:



You can see just how much the 15mm spacers push the front wheels out:

[sperry]

Oh, one other thing I forgot to mention.

When I was installing the tire-rods to the spindles, I found out the taper is different between the STi and SVX! During my mock-up phase I was just loosely installing them, and the diameters of the holes are the same on both knuckles... but when I went to tighten down the tire-rods, they wouldn't seat all the way.

Luckily, the taper the SVX tie-rods use happens to be the same 2in/ft taper the ball-joints use... so I just reamed out the steering arms on the STi knuckles to accept the SVX tie-rods. Took about 30 seconds to fix, but it does mean anyone else doing this job will need access to that $100 taper reamer in addition to slotting the upright mounting ears.

[SilverSpear]

Man that custom job is rated at 110/100 in my book.

Really pro!