SVX gravel rally car...surely not? Absolutely...

[SVXRide]

Originally Posted by oab_au

As Matt says, the spring rates suit the type of track that the car will run on. The actual spring rate has to be multiplied by the total strut travel. The rally car has to have a very soft initial rate to allow the wheels to keep traction on small bumps, but support the entire weight of the car over jumps, without bottoming the strut travel.

You can see by the way the spring is wound. It is progressively wound at each end, from tapered wire. This makes the rate very progressive, provides a supple ride, with a high total load.

The type of track that you all "auto cross" on is smooth and flat. No bumps at all, so the ideal set up is a very high spring rate, with very little strut travel. But if this set up is used on the 'real road', small bumps will have the car lose traction and skate across the road.

The standard suspension, is a low spring rate, with a long travel. Gives a supple ride, but can keep the car stable on high speed bumps, without getting out of shape.

Harvey.

Harvey,
I've been very interested in these pieces since Matt posted them. The parking lot at FedEx actually has a lot of on and off camber sections along with various drainage dips and elevation changes, so I've been working with GC to see what they can come up with in way of a progressive coil over for exactly the reasons you've noted. Only difference here is that the final rate will be ~100# higher than Matt's (no plans to go airborne! )
-Bill

[oab_au]

Originally Posted by SVXRide

Harvey,
I've been very interested in these pieces since Matt posted them. The parking lot at FedEx actually has a lot of on and off camber sections along with various drainage dips and elevation changes, so I've been working with GC to see what they can come up with in way of a progressive coil over for exactly the reasons you've noted. Only difference here is that the final rate will be ~100# higher than Matt's (no plans to go airborne! )
-Bill

I don't think you use enought strut travel to run progressive rate spring. You could use a two stage spring, that has a low rate for say 1" of travel, then ups to a higher rate for the last 2". I suppose 3" of travel is all that you would be using.?

The bump damping would have to accommodate the change of rate.

Harvey.

[SVXRide]

Originally Posted by oab_au

I don't think you use enought strut travel to run progressive rate spring. You could use a two stage spring, that has a low rate for say 1" of travel, then ups to a higher rate for the last 2". I suppose 3" of travel is all that you would be using.?

The bump damping would have to accommodate the change of rate.

Harvey.

Harvey,
I should have been more specific -- progressive in a "helper spring" way, which is exactly what you've described
The Koni inserts we're looking at are fully adjustable in compression and rebound.
-Bill

[TomsSVX]

Originally Posted by SVXRide

Harvey,
I should have been more specific -- progressive in a "helper spring" way, which is exactly what you've described
The Koni inserts we're looking at are fully adjustable in compression and rebound.
-Bill

Speaking of, when are they available... I will be needing to order thme soon because I need new struts in the teal really bad. This means I can pu the suspension from the silve ron the teal and put the DA on the silver with a set of GC's... Have we worked anything out yet where we have good clearances??

Tom

[SVXRide]

Originally Posted by TomsSVX

Speaking of, when are they available... I will be needing to order thme soon because I need new struts in the teal really bad. This means I can pu the suspension from the silve ron the teal and put the DA on the silver with a set of GC's... Have we worked anything out yet where we have good clearances??

Tom

Tom,
If my memory serves me right, Todd was going to do some work on the design this week and email it to me for review. We haven't had any indication of clearance issues so far - just looks like the strut housing will have to get spaced up to ensure the right amount of insert travel.
-Bill

[Dessertrunner]

Guys
The DMS's Matt and I got have a couple of benfits I ddin't see mentioned they give extended travel as compared to the standard and they can be adjusted to give the car a further 40mm (1.6in) ground clearance, with my tires we should get 4in. I got a set because hitting potholes or river crossing at speed was giving my car hell. The SVX is the toughest car Subaru ever built but I just needed to get the thing higher to clear thoses rocks and it is still cheaper and better then buying a big four wheel drive like every one else in the outback of Australia.
Tony

[SVXRide]

Originally Posted by Dessertrunner

Guys
The DMS's Matt and I got have a couple of benfits I ddin't see mentioned they give extended travel as compared to the standard and they can be adjusted to give the car a further 40mm (1.6in) ground clearance, with my tires we should get 4in. I got a set because hitting potholes or river crossing at speed was giving my car hell. The SVX is the toughest car Subaru ever built but I just needed to get the thing higher to clear thoses rocks and it is still cheaper and better then buying a big four wheel drive like every one else in the outback of Australia.
Tony

Tony,
I have no doubt that the DMS pieces that you and Matt have purchased are exactly what the Dr. ordered for your application! Maybe DMS can drop the price now that you've covered their NRE $
-Bill

[Trevor]

Originally Posted by Trevor

Greetings Matt,

Does this allow you to fit a quick rack to fix the rather low geared steering,
driver input being the most important consideration?

Cheers, Trevor.

Matt your reply would be appreciated as this essential performance requirement, appears to so far have no answers.

[dynomatt]

Trevor,

Apologies. The change to the column won't affect the steering rack as the WRX column has the same fitting on the end.

However, I haven't sourced the rack (nor, I confess, have I actively searched) so it's probably not front of mind.

I agree there's potential benefits, but at this stage, I'm focused on other outcomes.

Matt

[dynomatt]

Brake update:

I ordered some standard WRX calipers front and rear.

For those interested, the WRX 4 piston front calipers (not the Brembo's, although they would possibly work) bolt straight onto the SVX hubs. However, and this is probably of interest to you street guys who can run big wheels, the caliper sits further out than the SVX one does, meaning, for them to work, you would need much bigger discs.

This is a good thing, but as I run 15" wheels, it's useless to me.

I also checked the rears to match up the WRX 2 piston calipers, but the bolt spacing is all wrong, and I doubt they will be able to make work...but that's still a work in progress.

I will take some photos when I get back (away for about a week) of the calipers bolted up, and then some generic measurements in case any of you guys want to give them a go.

The WRX 4 pot runs about a 25mm thick disc (vs the SVX' 28) meaning any upgraded and larger disc would need to be the same thickness as the WRX.

So depending on what diameter you end up requiring, as long as you found the disc with the right height, and a 25mm thickness, you'd be on a winner.

I suspect that's what 'E' did but since he's gone AWOL, we don't full know.

Matt

[TomsSVX]

So the Red WRX calipers bolt right up. What about the rotor offest?? Will our rotors work with those calipers or would one have to have a wrx rotor drilled out to our lug pattern??

Tom

[dynomatt]

They bolt on. The offset is very close, but probably a few mm out, which is to do with slight differences in the SVX disc thickness vs the WRX disc thickness (28mm vs 25mm).

Our rotors will not work because the diameter is too small. Factory SVX discs are 301mm (I think) and due to the caliper mounting points, we would need a disck probably of 320mm at a guess.

WRX discs can be purchased (in Australia anyway, can't see why you guys are different) undrilled, meaning they could be redrilled, but I don't think they have a large enough diameter. Current STI rotors are 326mm, but have a 30mm thickness...too thick for these calipers.

Without any specific experience, I'd reckon you guys could bolt on the Brembo's at the front and the current STI rotors (being 5x114.3 would not require adaption) and bob would be your uncle.

But that's a guess...like everything, you'd have to try it first.

Matt

[TomsSVX]

F'it I am bidding on a set of front Brembos and rotors...

Tom

[-JJ-]

Originally Posted by TomsSVX

F'it I am bidding on a set of front Brembos and rotors...

Tom

i like the way you work

[Ottobon]

personally im interested in the SVX(havnt bought one yet ) as a comfy grand tourer, especially as some of them still have really beutiful interiors, but im really interested in seeing how this rally car comes out !!

please weigh it when your done and tell us the results