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Discussion Starter #1 (Edited)
I get a lot of questions about my setup, and sometime forget all the little things I have done, so I wanted to make a little thread documenting my trials and tribulations with the MK4 chassis. I already have an engine build thread over in the 1.8T forum ( http://forums.vwvortex.com/showthre...-GTT-E85-Build-Thread&highlight=gonzo+gtt+e85 ), so I will leave all of that stuff out of this thread. Cliff notes: I make about 355 HP and 370 TQ to the wheels.

Latest Setup (11/2014 and on)

2001 VW Golf 4 door 1.8T, built for SCCA F Prepared

Suspension, Braking & Steering
-Ground Control coil-overs with Advanced Design struts and shocks
-Ground Control upper adjustable camber/caster plates
-H2Sport drop spindles
-IDF tubular control arms with boot kit
-Powder coated OEM subframe with 034 billet bushing replacements
-OEM front sway bar with Prothane bracket bushings and Whiteline adjustable endlinks
-Shine rear sway bar with OEM rear bar retained
-SPC rear toe shims
-Strut bars (Autotech front lower, Yarrowsport rear upper)
-TyrolSport billet steering rack mount, EAA power steering delete loop
-OEM MK4 tie rods (soon to be replaced with complete beefier R32 tie rods)
-Wilwood 4-piston 12.19" front brakes
-Drilled/slotted rear rotors with EBC yellow pads, Goodridge braided lines.
-OZ Racing 16x7" Ultraleggeras with Dunlop Direzza Z1 Star Specs (225/50/16) for rain and HPDEs
-TSW Hockenheim R, 16x9" front, 16x7.5" rear with Kumho V710 r-comps (265/45/16 front, 225/50/16 rear) for dry Street Modified
-Riken Mesh 16x9.5" with Dunlop radial slicks, 42DD 20mm adapters for dry FP autocross

Weight Reduction
-Deleted A/C
-Deleted heater core and entire HVAC system (Gruven Parts)
-Deleted power steering (EAA Engineering) (back in for now..)
-Deleted factory oil/coolant heat exchanger system
-Denso racing alternator, relocated (EAA Engineering / INA)
-Deleted radio, amp, wiring and speakers
-Deleted all air bags, associated sensors and modules
-Deleted lower half of the dash and all interior panels
-Lexan front windshield, bracketed and removable side glass
-Carved out front doors (for cage door bars)
-Spare tire well cut out and replaced with a sheet of reinforced aluminum
-Deleted N249, SAI and EVAP equipment (IE resistor kit)
-Lightweight OZ Ultraleggera 16" wheels
-Lightweight Wilwood brakes
-Lightweight control arms
-Lightweight steel flywheel
-Lightweight Butler Built aluminum race seat
-Deleted rear and passenger seats
-Removed all padding, carpet, trunk mat, spare tire, tools and insulation
-Deleted 2/3 of the factory wiring harness
-Lightweight Deka ETX14 battery, relocated inside cabin
-Aluminum front bumper rebar (Shine Racing Service)
-Custom dry-weave carbon hood
-Seibon carbon fiber hatch

Safety
-Custom FIA-spec 8-point cage with padding, roof seams and NASCAR door bars on both sides.
-G-Force Pro Series 6-point harness
-G-Force window net
-5 panel rally-style rearview mirror
-Amerex Halotron fire bottle and mount
-Battery kill switch
-ZAMP RZ-34 Helmet
-G-Force triple layer SFI 3.2A/5 Suit
-TeamDI Delta6 2-layer Nomex gloves

Setup
-Front alignment set to -2.4 camber, +5.0 caster, -1/16" toe (out)
-Rear alignment set to 1/16" toe (in)
-Car has been corner balanced, and achieved a 50.2% diagonal spread
-I usually run the r-comps around 31 PSI front and 27 PSI rear for autocross, adjusting for temperature and course layout. For autocrossing on the Star Specs I usually add about 5 PSI to those numbers.
-Car runs the factory instrument cluster, plus gauges for boost, oil temp, oil pressure, EGT, and wideband O2. Center dash has connections for wideband O2 data and the extended factory OBD2 connector.
-Total weight is 2,240 pounds with a half tank of fuel and side glass installed.


Previous Setup (used until 10/2014)
I have owned the car since it was new in 2002, and it has spent most of that time and it's 120,000 miles as a dual-purpose daily driver and weekend fun car. A few years ago my car count went up, so I retired the GTI from regular street duty and morphed it into somewhat of a purpose-built track car, although I maintain the registration, inspection and insurance for limited street use. I used the car primarily for Autocross, competing locally in SCCA, PCA, and BMWCCAA events, and have been trying to do a couple of HPDEs a year.

The car moves extremely well around the autocross course, even with a very average driver (me) behind the wheel. The car has a lot of development, time and parts thrown into it, so hopefully my experience can help some others out determining what setup works for them. As far as suspension, the car has evolved from having the lowly OEM sport suspension, to a counter productive Weitec 40mm/40mm GT cup kit, to the benchmark Shine RSS kit, to custom Shine springs and rear coil perches, to it's current state with the H&R RSS ClubSports with a bunch of other goodies. Without further ado, here's my current build sheet:


2002 VW GTI 1.8T, prepared for SMF

Suspension, Braking & Steering
-H&R RSS ClubSport Coilovers
-Ground Control upper adjustable camber/caster plates
-Custom 1.0" tall aluminum spacer between the front coils and the GC upper plates
-R32 spindles and ball joints
-IDF tubular control arms with boot kit
-Powder coated OEM subframe with 034 billet bushing replacements
-OEM front sway bar with Prothane bracket bushings and Whiteline adjustable endlinks
-Shine rear sway bar with OEM rear bar retained
-SPC rear toe shims
-Strut bars (Autotech front lower, Eurosport front upper, Yarrowsport rear upper)
-TyrolSport billet steering rack mount
-OEM MK4 tie rods (soon to be replaced with complete beefier R32 tie rods)
-ECS 2-piece drilled/slotted 12.3" front rotors, EBC yellow pads, Goodridge braided lines, Tyrolsport caliper stiffening bushings
-Drilled/slotted rear rotors with EBC yellow pads, Goodridge braided lines.
-OZ Racing 16x7" Ultraleggeras with Dunlop Direzza Z1 Star Specs (225/50/16) for rain and HPDEs
-TSW Hockenheim R, 16x9" front, 16x7.5" rear with Kumho V710 r-comps (265/45/16 front, 225/50/16 rear) for dry autocross

Weight Reduction
-Deleted A/C
-Deleted radio, amp and speakers
-Deleted moonroof, replaced with an aluminum panel
-Deleted N249, SAI and EVAP equipment
-Lightweight OZ Ultraleggera 16" wheels
-Lightweight ECS 2-piece 12.3" brakes with EBC Yellows all around
-Lightweight control arms
-Lightweight steel flywheel
-Lightweight Corbeau Forza seats
-Deleted rear seats
-Removed all padding under factory carpet, trunk mat, spare tire, tools
-Lightweight Deka ETX14 battery
-Lightweight front bumper rebar
-VIS carbon fiber hood
-Seibon carbon fiber hatch

Safety
-Autopower 4-point Race Roll Bar
-Schroth 4-point DOT ASM harnesses
-Amerex Halotron fire bottle and mount
-ZAMP RZ-34 Helmet
-TeamDI Delta6 2-layer Nomex gloves

Setup
-Front alignment set to -3.0 camber, +8.0 caster, -1/16" toe (out)
-Rear alignment set to -1.5 camber, -3/32" toe (out)
-Car has been corner balanced, and achieved a 49.2% diagonal spread
-With the IDF lower control arms and Ground Control upper plates, the car can acheive a maximum of -3.5 degrees of camber. I sacrificed some of this for the improved caster/dynamic camber and street tire performance of my current settings.
-I usually run the r-comps around 31 PSI front and 27 PSI rear for autocross, adjusting for temperature and course layout. For autocrossing on the Star Specs I usually add about 5 PSI to those numbers.
-Total weight is 2,834 pounds with me (200 lb) and 5/8 tank of fuel. Dry weight is ~2,560.
 

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Jeff, before we get into it, what is the default spring rate on the RSS for your car? I have found that the default valving on those needed a boost in rebound to be ideal for autocross and a bit less compression.

When I drove your car, the biggest things that jumped into mind was the lack of rear rotation and the low front grip. The car had power but felt like it didn't want to be in an autocross, almost as if the front had all seasons and you left the rear at home (not near as lively as it need to be for solo). I would say your biggest improvement will come from jumping out of the oddball size and go 17 or 18" wheels/rubber. Your car needs 275+ rubber in the front... period. If I had a say, some 17X10 wheels and 315 r-comps will be in first order. As far as the rear, the amount of needed rotation, and ability to get heat generated, would dictate how much stagger and how meaty you need to go.

Once you can give me some info on your spring rate, we can jump into discussing suspension setup. :beer:
 

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Discussion Starter #3
The fronts are 571# and the rears are in the high 300s, I forget the exact rate. I'm not looking to change wheel and tire setups, as I'm happy with the current grip level and the price point of the tires I run. I ran 275 wide Hoosiers for one season up front, with 265 V710s in the back. The rears never got near temp and fronts had little improvement in contact patch over the 265s. Maybe with a 10" wide wheel and a squared shoulder it would be a different story.

Tim at Lynmor Motorsports took my car for a road test after completing the corner balancing and alignment, and commented that he thought the car had too much rear rotation, and should have the toe out in the rear zero'd out to address that. I personally like the balance the car has once the rear tires are up to temp. I've always raced FWD cars, so I'm not surprised my perspective on that varies from yours.
 

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Discussion Starter #5
Add some Dynamic Rear Steer< DRS and it will turn a lot better. MY book tells about how to get it right.
It is all about reducing the outer front tire loading.
Interesting, I might just check that out :thumbup:

Looks like there are big things in store for next year. New car and a new class :popcorn:
 

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Discussion Starter #8
Curious why you dropped back from -3 camber to -2.4? Do you think it handles better this way?


Thanks
It was a function of a couple of things. Changing tires from r-comps to true radial slicks don't seem to require as much camber to work at their peak. Also the suspension setups between those two measurements are completely different, now with drop spindles and race struts that are designed to work best at a lower ride height than stock, where before I had R32 spindles and H&R RSS coils on their that were modified to run closer to stock height. While the control arm geometry is perfect on my car, for whatever reason I sacrificed a bunch of caster, which lead me to dialing back the camber to recapture some of that. I haven't done extensive testing with the new setup yet, as final engine and drivetrain work is actually being completed today that's been holding me up.


Sent from my iPhone using Tapatalk
 

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It was a function of a couple of things. Changing tires from r-comps to true radial slicks don't seem to require as much camber to work at their peak. Also the suspension setups between those two measurements are completely different, now with drop spindles and race struts that are designed to work best at a lower ride height than stock, where before I had R32 spindles and H&R RSS coils on their that were modified to run closer to stock height. While the control arm geometry is perfect on my car, for whatever reason I sacrificed a bunch of caster, which lead me to dialing back the camber to recapture some of that. I haven't done extensive testing with the new setup yet, as final engine and drivetrain work is actually being completed today that's been holding me up.


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Cool, hope you share the results. My current setup is similar to your old one. Do you think I'd notice a difference at HPDEs if I went from -2.2 to -3?
 
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