johnfm

guys

I suspect my MK1 GT3 ride height is set too low. My own crude measurements (ie crawling under the car in my garage measuring from the hex head bolt at the front and locating bore in the rear as per the manual) suggest the front and rear are lower than the specs (102 - 112 mm front, 125 - 135mm rear).

my measurements tell me the front is at about 99mm and the rear is 110 mm.

What adverse effects on handling would you predict from this.

FYI, alignment is bang on factory specs.

Look forward to any opinions from suspension gurus.

Mr. C4

John,

My Mk.1 Clubsport is also very very low and I haven't lowered it! It's been given a more track oriented alignment and corner balance and is almost undriveable around town with just 1 inch clearance at the front lips lowest point.

Ciao,

Johannes

johnfm

Cheers Johannes

Nice colour you have there!!

The clearance isn't the issue for me - its front end grip. I find my ABS kciks in very easily - I expect the front end grip may be being compromised by the excessive lowering. I wonder if the suspension is running out of compression travel, so the front end has trouble keeping the tyre in contact over choppy surfaces. I intend to get the ride height set to 'proper' levels in a few weeks, but in the interim I was hoping for some experienced opinions.

FTS

I'd suspect you are not having enough suspension travel, hence minimizing amount of weight tranfer to the corners (or front in this case) and loosing on mechanical grip, which is directly proportionate to amount of controlled weight transfer.

Greg Fishman

How much negative camber do you have? If you have over 3 degrees it maybe an issue of tire contact, or rather lack of contact. Everything else being equal you get camber gain as you lower a car.

johnfm

Neg camber is 1.6 in the fornt and about 2 in the back, IIRC. I think it may be a suspension travel thing at the front. I'll know when the heights are reset - I think the one of the previous owners messed it around a bit.

NJ-GT

You can lower the car but you might have to consider these additional adjustments:

- Angle on rear toe arm. Bump steer at the rear is really scary. The GT3 Cup uses spacer rings to adjust that angle. I've (2) 5mm rings to compensate for a 10mm lower car at the rear.

- Angle on the steering link. Bump steer at the front is not scary, but it's bad enough. You can adapt a GT3 Cup toe link to the steering rod, and use the same spacer rings to reduce bump steer, or use the GT3RS uprights.

- Stock shocks compression is not adjustable, spring rates are not stiff enough, and you might run into the bump stops front and rear. That's plenty scary.

- There are miscelaneous effects such as rubbing the fender liner front and rear, rear wheels rubbing the trailing arm, front tires rubbing the fenders on high speed turns....

How do I know? I've been there, done that.

chris walrod

Your lack of front grip [while on the brakes] could be an issue of too much camber gain. Typically, lower front ride heights yield increased camber gain while in bump travel on just about any car.

I assume your chassis rake is fine?

Mr. C4

John,

My ABS kicks in rather early with street tires but there is still plenty of suspension travel (lip scratches at the bottom Ex-Muhle at the Nurburgring). With R compound tires fitted the ABS is fine. The ABS issue is a common problem on GT3's.

Ciao,

Johannes E.

johnfm

Thanks Johannes & others

I will be getting ride height & full alignment check in next couple of weeks & let you know. I will be replacing all the tyres too - I'm wondering if I should do tyres first to see if they are the culprit of my handling issues - if I do tyres & alignment at the same time I won't know what affected the handling most!