Racing/Track setup - your thoughts/help pls!

[HummuH 10]

Hi all, after my first years racing the Turbo'd G60 I have fallen for Corrado's again.

 

Needless to say, I'm looking to make small improvements for this year, principally to suspension and geometry. I'm running KW Compeition coilovers with 0 camber on the rear and about -1.5 on the front. Big front and rear ARB's, not sure of size but they are thick. Wheels are 16x7.5j Compomotive MO5's running 224/45 Yokohama's A048R's with a Peolquin Torque biasing diff mated to a 02J box. Shocks are set to pretty much medium all round.

 

I'm very much a newb when it comes to Geo and Corrado's so was looking to pick your brains. The issues I'm experiencing are:

 

1. Mid corner understeer with light throttle.

2. Front end will sometimes "bunny-hop" mid-corner.

3. Lack of traction in 2nd gear on throttle, when cornering and on the straights in the dry. This is chewing through the tyres.

 

My first thoughts were to add more camber front and rear to about -2 front and -1 rear. I have some Eibach front camber bolts and some Eibach rear camber/toe shims - these up to the job?

 

The car is very stiff and I feel it could be too low reducing the amount of travel. It feels too stiff, almost like it isn't allowing enough weight to transfer on to the loaded wheel. On this basis, I've thought of trying it with the ride height raised a bit and the front ARB disconnected. There's a couple of images below. One shows the ride height and the other shows how little body roll there is coming out a tight corner.

 

Any help or opinions you can offer would be much appreciated. Thanks.

 

 

[onestep 0]

Hi

 

Nice corrado is this jabbasports old car?

There is quite a few things you can do to improve handling

Rose joint the front wishbones and the rear beam.

Seam weld the wish bones.

Splitter on the front.

Triangulate the rear beam with rose joint adjustable bars.

That pretty much what im doing to my to improve on handling on track.

Corner weighting

[HummuH 10]

Hi. Yeah, it's Jabba's car. They've been really helpful so far.

 

Thanks for the tips, that's maybe next years budget right there! Was looking at the rear beams yesterday. Where are you getting your parts from?

 

Any tips on what camber to aim for as a starting point and what's your take on ride height?

 

Cheers!

[Dox 23]

http://www.ebay.co.uk/itm/VW-MOTORSPORT-GOLF2-3-JETTA-CORRADO-VENTO-ANTI-TOE-TORSION-BEAM-AXLE-EXCH-/190769477913?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c6abf3919&nma=true&si=4SWJfrq%2BzE58TdtWaKVoSdL9cuk%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

[onestep 0]

Hi. Yeah, it's Jabba's car. They've been really helpful so far.

 

Thanks for the tips, that's maybe next years budget right there! Was looking at the rear beams yesterday. Where are you getting your parts from?

 

Any tips on what camber to aim for as a starting point and what's your take on ride height?

 

Cheers!

 

You can download the pdf file off the internet for the vw motorsport engineering loads of good stuff on there.

 

Im having a company make me some of the parts.

 

As for the rose joints you can make your own or buy the vibra tech http ://www.vibra-technics.co.uk/vw/corrado/388/VAG810B/front_lwr_arm_rear_bushes_singlehttp ://www.vibra-technics.co.uk/vw/golf_jetta_mk_ii/395/VAG990B/rr_beam_pivot_bushes_single

Edited January 10, 2013 by onestep

[Ralphead 0]

My feelings are to, as you say, disconnect the front arb to keep that inside wheel planted and raise the front ride height a bit to let the suspension do its thing.

 

The wishbones should be at least level when static. If the ball joint ends go too far above the other end then you'll get extra negative camber on compression rather than zero, or near to zero, which is the aim when setting static negative camber.

 

I'm running 1.5 degrees camber up front but I only drive it on the road so not really relevent.

[coullstar 0]

Can't say much more than the guys have already said but they do seem to be better with the wishbones as near level as possible. Do you have a an LSD? What powers it running and have you changed the map? My old vr turbo was the same on track at knockhill in the wet if you were heavy with the throttle.

[Metallix 10]

What benefit do you get from:

Rose joint the front wishbones and the rear beam.

Seam weld the wish bones.

Splitter on the front.

Triangulate the rear beam with rose joint adjustable bars ?

 

^^^ this doesn't address the points he intially raised.

 

 

You need to find out/ list what spring rates you have on your Corrado

The camber you are running is milder than some road cars, try -2.5 or even -3 on the front

What toe setings are you running?

You have adjustable dampers so if the front is understeering crank up the rear dampers and/or reduce the front damping

 

Eibach camber bolts work fine, you can use one per side for low numbers or two if even more camber required,

or get the hole file out and make the hole on the suspension strut more of a slot.

[HummuH 10]

http://www.ebay.co.uk/itm/VW-MOTORSPORT-GOLF2-3-JETTA-CORRADO-VENTO-ANTI-TOE-TORSION-BEAM-AXLE-EXCH-/190769477913?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c6abf3919&nma=true&si=4SWJfrq%2BzE58TdtWaKVoSdL9cuk%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

 

Thanks, that was what I was looking at.

 

You can download the pdf file off the internet for the vw motorsport engineering loads of good stuff on there.

 

Im having a company make me some of the parts.

 

As for the rose joints you can make your own or buy the vibra tech http ://www.vibra-technics.co.uk/vw/corrado/388/VAG810B/front_lwr_arm_rear_bushes_singlehttp ://www.vibra-technics.co.uk/vw/golf_jetta_mk_ii/395/VAG990B/rr_beam_pivot_bushes_single

 

Cheers, any links to the pdf, can't seem to easily find it? How would these work with a Peloquin torque biasing diff?

 

My feelings are to, as you say, disconnect the front arb to keep that inside wheel planted and raise the front ride height a bit to let the suspension do its thing.

 

The wishbones should be at least level when static. If the ball joint ends go too far above the other end then you'll get extra negative camber on compression rather than zero, or near to zero, which is the aim when setting static negative camber.

 

I'm running 1.5 degrees camber up front but I only drive it on the road so not really relevent.

 

Thanks, very useful to know.

 

Can't say much more than the guys have already said but they do seem to be better with the wishbones as near level as possible. Do you have a an LSD? What powers it running and have you changed the map? My old vr turbo was the same on track at knockhill in the wet if you were heavy with the throttle.

 

Running a Peloquin diff. Power quoted at 315bhp but I have no idea if it's running that still. Going in for a turbo health check/dyno in about 4 weeks so will know then. I'm having issues with traction in the dry. Can't get out of the hairpin in 2nd, the wheels just light up and I lose about 1 sec of time. 3rd gear is off boost on exit so can't really use it.

 

What benefit do you get from:

Rose joint the front wishbones and the rear beam.

Seam weld the wish bones.

Splitter on the front.

Triangulate the rear beam with rose joint adjustable bars ?

 

^^^ this doesn't address the points he intially raised.

 

 

You need to find out/ list what spring rates you have on your Corrado

The camber you are running is milder than some road cars, try -2.5 or even -3 on the front

What toe setings are you running?

You have adjustable dampers so if the front is understeering crank up the rear dampers and/or reduce the front damping

 

Eibach camber bolts work fine, you can use one per side for low numbers or two if even more camber required,

or get the hole file out and make the hole on the suspension strut more of a slot.

 

Thanks. Unfortunately, I have no idea on spring rates. I tried some adjustments to reduce understeer last season and whilst they did help, I think I need some more fundamental changes to improve the handling, at Knockhill specifically. The fact it's a very bumpy track doesn't help!

 

Thanks to all for your help. Feel free to add anything further! Cheers.

[Metallix 10]

Sometimes spring rate is indicated by a part number / manufacturer code / painted colours on the springs.

 

Ask previous owner / KW?

 

You do need to know what you have got on there.

 

Are you running flat spoke Compomotive MO wheels?

[HummuH 10]

Cheers. Gonna have a look over the weekend and see if there's any clues!!

 

Yep got the heavy flat spoked MO5 wheels. Currently looking for a lighter 16x7.5 set but not a huge amount of options.

[Metallix 10]

They are heavy for an alloy wheel,

I have flat spoke version in 15x8" & they are weighty indeed.

 

A lighter wheel should help with the bumpy surface you describe at Knockhill. (not to mention easier to speed up & slow down it's rotation)

[HummuH 10]

http://www.ebay.co.uk/itm/VW-MOTORSPORT-GOLF2-3-JETTA-CORRADO-VENTO-ANTI-TOE-TORSION-BEAM-AXLE-EXCH-/190769477913?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c6abf3919&nma=true&si=4SWJfrq%2BzE58TdtWaKVoSdL9cuk%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

 

Just for info, I saw one of these items in the flesh today. Wouldn't go anywhere near it personally. Welding was not good at all.

[jezzaG60 0]

I would run a softer front ARB.

[Ralphead 0]

How much do you play with the tyre pressures? Tyres have the last word in traction so pressures can make such a difference.

My tyre inflator for my air compressor failed and for a couple of months I was relegated to the the Tesco petrol station compressor. After a week or so the cars handling just didn't feel right. Last week I bought a proper gauge and found Tescos digital peice of crap is out by over 10 percent! Both ways! I had 45 psi in one front tyre and 38 in the other.

 

As for camber, I was running 1.5 at standard height but actually went back to under 1 when I lowered my suspension by 40mm. More static negative camber isn't automatically good. The whole point is to have the wheel upright (zero camber) when cornering, therefore giving the biggest tyre "footprint" you can. What your static setting should be depends on how much your suspension compresses when cornering.

My setup is not scientific and is done on gut feeling and a little maths. Track work should give you the oppurtunity to really test any changes.

 

Oh. Dibs on those wheels if you change them, they're cool as.

[HummuH 10]

I would run a softer front ARB.

 

Cheers, any recommendations for front ARB? Like I say, I don't know the dimensions of the current one but it must be about as thick as you could possibly get on a Corrado.

 

---------- Post added at 1:31 PM ---------- Previous post was at 1:26 PM ----------

 

How much do you play with the tyre pressures? Tyres have the last word in traction so pressures can make such a difference.

My tyre inflator for my air compressor failed and for a couple of months I was relegated to the the Tesco petrol station compressor. After a week or so the cars handling just didn't feel right. Last week I bought a proper gauge and found Tescos digital peice of crap is out by over 10 percent! Both ways! I had 45 psi in one front tyre and 38 in the other.

 

As for camber, I was running 1.5 at standard height but actually went back to under 1 when I lowered my suspension by 40mm. More static negative camber isn't automatically good. The whole point is to have the wheel upright (zero camber) when cornering, therefore giving the biggest tyre "footprint" you can. What your static setting should be depends on how much your suspension compresses when cornering.

My setup is not scientific and is done on gut feeling and a little maths. Track work should give you the oppurtunity to really test any changes.

 

Oh. Dibs on those wheels if you change them, they're cool as.

 

Thanks, I played around with pressure a lot. I get c. 8/9 psi of a lift from cold to warm on the front, about 5 psi on the rear. Best pressure for the front in the dry is about 21 psi cold I have found.

 

I'm gonna lift the height a bit say 10mm to 15mm, run a smaller front ARB and start at -1.5 front and -1 rear and see how that feels as a starting point.

[Ralphead 0]

Cheers, any recommendations for front ARB? Like I say, I don't know the dimensions of the current one but it must be about as thick as you could possibly get on a Corrado.

 

There must be some pretty skinny ones on some of the smaller engined mk2 Golfs. It would be worth trying no arb at all, according to pure suspension theory they aren't great devices. The more independent either side can be the better. I fitted twin arbs on my Volvo as a cheap way to try and calm it down a bit but took the second rear one off soon after as it was causing all sorts or inside wheel lift "fun"