STi brakes, the brute force way!

[Crazy_pilot]

Correct me if I'm wrong guys, but don't most aftermarket calipers have a separate bracket that allows the caliper to mount to the knuckle, meaning that a single caliper can be used on multiple cars by using a different bracket? If this is the case, why couldn't we take any off the shelf STi BBK (rotors would fit), and have a pair of brackets custom machined to adapt the caliper to the stock SVX knuckles? when you consider the cost of most BBKs I don't think a pair of special brackets would be a devastating addition.

[sperry]

Originally Posted by Crazy_pilot

Correct me if I'm wrong guys, but don't most aftermarket calipers have a separate bracket that allows the caliper to mount to the knuckle, meaning that a single caliper can be used on multiple cars by using a different bracket? If this is the case, why couldn't we take any off the shelf STi BBK (rotors would fit), and have a pair of brackets custom machined to adapt the caliper to the stock SVX knuckles? when you consider the cost of most BBKs I don't think a pair of special brackets would be a devastating addition.

That's precisely how StopTech calipers work. Willwood too if I'm not mistaken. Unfortunately, custom machining of those brackets tends to be non-trivial as they need to be machined in two dimensions. i.e. they're not just flat brackets. You have to take into account the mounting holes on the back of the spindle, the radius of the brake rotor, and the offset of the rotor to the hub mounting face.

In comparison to the cost of the work that I did with the hub swap, it probably wouldn't be that expensive if you got a shop that knew what they were doing. But you also wouldn't get the heavy duty STi unit hubs out of the deal either, which was something I was very interested in for tracking the SVX.

[Crazy_pilot]

With what I've seen of those brackets I don't think it would be overly difficult. Part of my college program was machine shop work, CNC, design, etc. I don't think it would be too hard with a decent 3-axis CNC mill and some CNC programming know-how.

But yes, it is definitely beneficial to get the STi's front hubs. The ease of replacement alone would be a good reason for the swap if the car is going to be seeing track time. I remember seeing pictures a while back of a completely custom CNC aluminum knuckles for an STi. I really wish I could find them again, it was some amazing work.

[XT6Wagon]

[QUOTE=sperry;677113]Thanks for the support!
A set of coilovers could very well have been the fix-all for the shudder... QUOTE]

Might have been a good next step as I'm guessing using 05+ STi struts with a tophat that matches the SVX strut tower would have fixed the clearence issues (all STi geometry around the rim/tire).

But given the time and money you already put into this, and not knowing when the road ended... can't fault you at all for stopping.

[Nemesis Destiny]

As concerns mounting aftermarket calipers and rotors, I believe another member* had been working on such a project to make an inexpensive kit for our cars, however he ran into some snags.

Namely that brake hardware must, for safety reasons, be manufactured of the highest quality materials. He had a batch of caliper horns made up but when he had them x-rayed, found the quality lacking - the metal had numerous micro-fractures in it and was therefore unsuitable.

If you have access to better quality stuff, there is no reason that this wouldn't work.

That said, the big plus here is that, as noted, you get the STi hubs, and that you can use anything designed for a car with a huge aftermarket.

[smc]

Originally Posted by /

However, if some brave individual is interested in the prototype bits, I'm happy to sell them off to you (with no warranty of course... I can't guarantee you'll be happy with the kit... it's a work-in-progress after all!).

The parts I'd be selling:

- STi front spindle/hubs, modified for SVX fitment (slotted uprights, drilled for SVX tie-rod ends), also modified to fit StopTech BBK
- WRX ABS sensors, brackets modified for SVX fitment
- STi front axles, modified for SVX gearbox fitment
- STi front axle seals (requires removal of the gearbox sundials for installation)
- STi ball joints
- Custom fabricated ball-joint adapter
- Ichiba 15mm wheel spacers, ARP extended lug bolts in the hubs
- Custom length Hotchkis endlinks

Well, seems im that fella. I just picked up his setup for my SVX which im turning into a track/rally car. Once I get it installed, ill check the suspension geometry, akerman angle, roll center etc. etc. I may do some fine tuning then get the ball joint adapter milled from from billet for added strength. After some testing to ensure that it will stand up to a beating, ill make it into a swap kit for my fellow SVX owners

[sperry]

Originally Posted by smc

Well, seems im that fella. I just picked up his setup for my SVX which im turning into a track/rally car. Once I get it installed, ill check the suspension geometry, akerman angle, roll center etc. etc. I may do some fine tuning then get the ball joint adapter milled from from billet for added strength. After some testing to ensure that it will stand up to a beating, ill make it into a swap kit for my fellow SVX owners

Thanks again Shaun! I'm stoked someone is going to run with this idea.

My guess I'd that a nice water jet cut version of the adapter would be a benefit, especially if you can slim it down a bit for better clearance with large brake rotors.

I'm not sure I'd use billet aluminum. The adapter would have to be pretty massive to be as strong as steel, not to mention the better flexibility steel has in a rally environment. Always better to finish the stage with a bent part than to have to park it with a broken part.

[smc]

Originally Posted by sperry

Thanks again Shaun! I'm stoked someone is going to run with this idea.

I'm not sure I'd use billet aluminum.

Steel billet. IE milled from a solid chunk Hey man, anything we can do to keep our beloved SVX's on the road, plus open the possibilities of STI upgrades. Im all for it!

[smc]

I bolted up a knuckle assembly last night and took some measurements. This was with out a brake assembly attached on it however, so no road test. The adapter bracket drops the lower suspension linkage downward by a small amount over stock and, as was noted, indeed moved the wheel mounting surface inward by approx 1.24" under that of stock. Wheel spacers with hub centric rings will be provided to compensate for this. However, If your planning on swapping in STI knuckles there is some good news with this. The relocation of the lower linkage is perfect if you are lowering your car. With 2" of suspension drop, you will still have near perfect angles on your suspension for stock rollcenter. If anything, it helps with the gobs of lift that is built into the stock suspension by acting as something of an anti-lift kit. If you plan on dropping even lower than 2", there are kits for the STI that relocate the balljoint for better geometry.
Scrub radius is affected as the centerline of the strut to the balljoint has now shifted off center of the wheel and has moved inward due to the spacers that are needed to compensate for the reduced width of the STI knuckle assembly. None of this is bad enough to worry about. I doubt that it will have any significant changes to the suspension dynamic at all.

Sperry, you did a damn nice job, man!


Ontop of this, I went ahead and dropped off the bracket and spacers at a machine shop and they are working up a quote for me on 10 kits. These will work to swap in both front STI and WRX knuckles into our cars. Ill get you guys a price as soon as I get it.

[Nemesis Destiny]

Nice! Glad to hear progress is being made on this again. Very exciting!

[smc]

Yeah man! Opens up a world of possibilities in regards to brakes, suspension and bearings for our cars. The rear STI knuckles are just a bolt in procedure with an axle shaft swap. You just need to fab up a spot for the swaybar linkage. So no big deal on the back end. Its the front that has been giving us hell.

For the front swap, you will need: STI knuckes (with brakes etc. etc.) ABS sensors from a WRX or STI, as ours will no longer work with these knuckles. WRX or STI axle shafts of the same year and make of knuckle your swapping in.

Included in the swap kit: 2: Balljoint adapters from STI to SVX milled from a block of 4340 steel. 2: Wheel Spacers, 2: Hubcentric Rings and 2: steering adapters. New longer wheel studs.

Easy peasy.

[92 SVX]

Originally Posted by smc

Yeah man! Opens up a world of possibilities in regards to brakes, suspension and bearings for our cars. The rear STI knuckles are just a bolt in procedure with an axle shaft swap. You just need to fab up a spot for the swaybar linkage. So no big deal on the back end. Its the front that has been giving us hell.

For the front swap, you will need: STI knuckes (with brakes etc. etc.) ABS sensors from a WRX or STI, as ours will no longer work with these knuckles. WRX or STI axle shafts of the same year and make of knuckle your swapping in.

Included in the swap kit: 2: Balljoint adapters from STI to SVX milled from a block of 4340 steel. 2: Wheel Spacers, 2: Hubcentric Rings and 2: steering adapters.

Easy peasy.

Are these needed if you use a lower offset rim? and lowering springs?

[smc]

Yes. The spacer simply moves the wheel mounting surface back to SVX stock location.

[92 SVX]

Originally Posted by smc

Yes. The spacer simply moves the wheel mounting surface back to SVX stock location.

Im sorry I am most likely saying it wrong.
put it this way stock wheel offset for this car is
+55 and as shown

Originally Posted by svxcess

a lower offset, say +38 would bring the mount point in side causing the rim edge to stick out farther.

[smc]

Ahh. Got ya. I thought you meant wheels that were already installed on the car with the lower offset. You can indeed just use rims with a lower offset as apposed to the alum. spacers.