Ultimate street car suspension... ?

For road racing, autocrossing, or just taking that curve in style. Oh yea, and stopping!
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Piledriver
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Re: Ultimate street car suspension... ?

Post by Piledriver »

Thank you!

CSP also sells vented replacement discs, as part of a kit and by themselves, these custom units made by Sebro:
http://www.csp-shop.com/cgi-bin/cshop2/ ... fied%20PCD

Sadly CIP1 nor Wolfsburg West (USA CSP Resellers) do not seem to carry these.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
Steve Arndt
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Joined: Sat Mar 10, 2001 12:01 am

Re: Ultimate street car suspension... ?

Post by Steve Arndt »

Pierside Parts sells the vented "ghia" Kerscher rotors. $150 bucks a pop last time I asked.
vwo60
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Re: Ultimate street car suspension... ?

Post by vwo60 »

Good value, I always laugh when I see brakes like the BAD series with the standard calliper and steel rotor, no increase in braking just appearance and all the kits have solid rotors, marketed as a performance brake kit. these are the front set I made for my early beetle, billet hubs, RX 7 four spot callipers and a 300MM vented rotor.
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jhoefer
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Re: Ultimate street car suspension... ?

Post by jhoefer »

Jprather wrote:
jhoefer wrote:
Jprather wrote:Will I have too much negative scrub?
You won't have a negative scrub radius, you'll be making your car's original positive scrub radius larger. The drop spindles increase scrub by moving the tire outward (further away from the balljoint steering axis). Running wheels with a lower ET also moves the tire centerline outward, increasing scrub radius. You are going to feel an increase in steering effort, an increase in kickback from the steering wheel over bumps and under braking. Could make parking lot steering easier however.
That doesn't sound too good. I wanted to lower the car with drop spindles so I didn't change the geometry too much.

The fiberglass fenders don't give me to much room to work with, about 2" from the face of the rotor to the edge of the fender.

Any other thoughts on how to make this work? Would a 5" rim improved the situation? Or 7"?

I'm open to any suggestion. I just want a good looking VW that's fun to drive. I have never altered a VW before so this is all new.
Given your options, I'd personally just run your existing beam width and change to a wheel width and offset that will get flush with the wheel well. Going from your original specs, 6" ET+50, 5.5" ET+45, 5.0" ET+38 would all account for not narrowing the beam 2".

Three ways to reduce scrub radius:
1) Larger diameter tires. Aesthetics usually wins out here so probably not an option. Also, diameter increases are large for the amount of scrub reduction you get.
2) Larger ET wheels. Scrub radius is relative to the center of the contact patch, width of the tire won't move this much. Larger ET moves the contact patch closer to the car. As vwo60 mentioned, he went to +50mm to correct his. But offsets that high can be hard to find, but wheel offset is the most common method to alter scrub radius.
3) Widen the front beam (or in your case do NOT narrow the beam). This will push the spindles out and you can run a more standard VW offset wheel that will fill out the wheel well without needing to use the low ET/high width rims.

Otherwise, the scrub radius is determined by the ball joint locations which you can't do anything about without a custom suspension and spindles. Lowering the suspension with an adjustable beam will reduce ride comfort and can affect bump steer. Unfortunately, suspension design is all about acceptable compromises.
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Piledriver
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Re: Ultimate street car suspension... ?

Post by Piledriver »

Hmmm I might have to make up some hubs for a T3...

One common setup for Porsche racers is to use the surprisingly cheaper late model rotors for the Cayenne over cut down stock hubs. (have cast in hats/one piece vs bolt onto the alloy hub)
Last edited by Piledriver on Mon Jun 09, 2014 4:32 pm, edited 1 time in total.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Fiatdude
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Re: Ultimate street car suspension... ?

Post by Fiatdude »

MENDEOLA has some bitchen brakes -- but I believe you need 17"+ rims to run them
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Piledriver
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Re: Ultimate street car suspension... ?

Post by Piledriver »

Fiatdude wrote:MENDEOLA has some bitchen brakes -- but I believe you need 17"+ rims to run them
The Mendeola setups I have seen were shown with Airkewld..

ET40++ rims are very common on modern vehicles.
Getting them in under 17" is getting more difficult...
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
Chris V
Posts: 3416
Joined: Tue Sep 03, 2002 12:01 am

Re: Ultimate street car suspension... ?

Post by Chris V »

Finding narrow 17" rims for placement on the front, under a stock fender along with a lowered ride height is challenging. Last I checked a couple OEM Porsche Cayman rims were offered in 17x6.5 ET55.

OEM 944 & 986 based kits are also an option increasing component selection and vendors - http://vdubengineering.com/brake-parts-kits/
Critter1
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Re: Ultimate street car suspension... ?

Post by Critter1 »

In my original post I didn't mention.. I'll be running wheels with 4x130 pattern, which makes it all that more difficult to find vented/drilled rotors. I like the Kerscher vented/drilled rotors. On their site they only list the kits. I emailed inquiring if they'll sell the rotors only.

BTW.. I'm liking all the replies in this thread. A lot of the info I was looking for, all in one place!!
Critter1
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Re: Ultimate street car suspension... ?

Post by Critter1 »

Fiatdude wrote:Critter -- drop what you're doing and race over to the east coast and get this car -- it is a steal

http://www.thesamba.com/vw/classifieds/ ... id=1645751

\Here is the build thread

http://www.shoptalkforums.com/viewtopic ... 1&t=141621
WOW.. that is one helluva deal. You'd eat up $7k in no time and not be anywhere near where that build is as it sits! Florida.. hmmm.
Chris V
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Re: Ultimate street car suspension... ?

Post by Chris V »

Critter1 wrote:In my original post I didn't mention.. I'll be running wheels with 4x130 pattern, which makes it all that more difficult to find vented/drilled rotors. I like the Kerscher vented/drilled rotors. On their site they only list the kits. I emailed inquiring if they'll sell the rotors only.

BTW.. I'm liking all the replies in this thread. A lot of the info I was looking for, all in one place!!
These custom hubs will open up a world of options:
http://vdubengineering.com/products/bra ... llet-hubs/
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Jprather
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Re: Ultimate street car suspension... ?

Post by Jprather »

jhoefer wrote:
Jprather wrote:
jhoefer wrote:
Jprather wrote:Will I have too much negative scrub?
You won't have a negative scrub radius, you'll be making your car's original positive scrub radius larger. The drop spindles increase scrub by moving the tire outward (further away from the balljoint steering axis). Running wheels with a lower ET also moves the tire centerline outward, increasing scrub radius. You are going to feel an increase in steering effort, an increase in kickback from the steering wheel over bumps and under braking. Could make parking lot steering easier however.
That doesn't sound too good. I wanted to lower the car with drop spindles so I didn't change the geometry too much.

The fiberglass fenders don't give me to much room to work with, about 2" from the face of the rotor to the edge of the fender.

Any other thoughts on how to make this work? Would a 5" rim improved the situation? Or 7"?

I'm open to any suggestion. I just want a good looking VW that's fun to drive. I have never altered a VW before so this is all new.
Given your options, I'd personally just run your existing beam width and change to a wheel width and offset that will get flush with the wheel well. Going from your original specs, 6" ET+50, 5.5" ET+45, 5.0" ET+38 would all account for not narrowing the beam 2".

Three ways to reduce scrub radius:
1) Larger diameter tires. Aesthetics usually wins out here so probably not an option. Also, diameter increases are large for the amount of scrub reduction you get.
2) Larger ET wheels. Scrub radius is relative to the center of the contact patch, width of the tire won't move this much. Larger ET moves the contact patch closer to the car. As vwo60 mentioned, he went to +50mm to correct his. But offsets that high can be hard to find, but wheel offset is the most common method to alter scrub radius.
3) Widen the front beam (or in your case do NOT narrow the beam). This will push the spindles out and you can run a more standard VW offset wheel that will fill out the wheel well without needing to use the low ET/high width rims.

Otherwise, the scrub radius is determined by the ball joint locations which you can't do anything about without a custom suspension and spindles. Lowering the suspension with an adjustable beam will reduce ride comfort and can affect bump steer. Unfortunately, suspension design is all about acceptable compromises.
I am running p205/75/r15 tires. They are just over 26" in diameter. Would that compensate or improve the scrub radius?

I am having a hard time finding finding rims with an ET45 or higher. Maybe I'm not searching correctly.

As a back up, I believe the stock VW chromies have a shallow front space less than 2". I was hoping to do something a little more interesting but ultimately I just want the car to handle.
jhoefer
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Re: Ultimate street car suspension... ?

Post by jhoefer »

Jprather wrote:I am running p205/75/r15 tires. They are just over 26" in diameter. Would that compensate or improve the scrub radius?

I am having a hard time finding finding rims with an ET45 or higher. Maybe I'm not searching correctly.

As a back up, I believe the stock VW chromies have a shallow front space less than 2". I was hoping to do something a little more interesting but ultimately I just want the car to handle.
26" is pretty much the same as stock, so no it wouldn't do much.

Yeah, ET45 is about the limit for common aftermarket wheels in the sizes you want. For wheels more commonly found on VWs, the 5.5 ET45 Fuch replicas could be a choice, but you'd still have to change bolt patterns on the drums/discs.
vwo60
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Re: Ultimate street car suspension... ?

Post by vwo60 »

If you go to all the trouble of changing the stud pattern then you can use one of the many Porsche wheels that have a ET of 55mm +
coolrydes
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Re: Ultimate street car suspension... ?

Post by coolrydes »

Hey guys we have two sizes of front cross-drilled and vented front Cool Stop brake packages with Wilwood 4 piston calipers. They come in 11" for 15" inch wheel guys, and 12.5" for the 17" inch wheel guys. Take a look at them on mendeolasuspension.com
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Kevin "Coolrydes" Zagar
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