I've done a number of upgrades recently and although the car is *tons* better I think there are two areas I'm looking to improve:

Steering turn-in: This thing still feels like turning the Titanic. Numb feel and seems like too much travel is required to get the wheel back and forth for slaloms. Camber is set -1.5 on each side.

Pushing: Handling is still not 'neutral' and the front still has some understeer. Wondering if that is partly an effect of adding the S/C weight (e.g what would now be balanced on an N/A GT, understeers on my nose heavy GT).

Aftermarket parts installed:

Koni 'Yellows' turned 360 front/rear
Front strut mounts
Vogtland springs (.8/1.2)
Adjustable UCA/LCAs (rod ends)
Saleen Watts Link
GT500 OEM rear stabilizer bar

Thoughts?

 

What size tires are you running front and rear?

 

275/35ZR18 all around

 

Hi 2007GT/CS,

Need more data! What wheels, wheel sizes,tires and tire sizes are you running? Are you running staggered wheels or tires or staggered wheels AND tires?

Did you buythese nonstandard Vogtland springs froma companythat mixedthe springs from various other S197 Mustang spring sets? If so this could be part of theproblem it they used a stiffer GT500 spring and matched it up with a normal GT rear spring. They may have doneyou a dis-service and gave you ahigher ratefront spring rate and a regularrear spring rate to get the ride heightspecs they showed. This would tend to make the car push more than it seems it should.AFAIK Vogtland does not have a regular catalog part number with these ride height specs.

What is the toe spec you used? Did you get a print out to see what your front end is set to?

On level ground what do your LCA's look like? Are they level or pointing up at the rear axle or pointing down to the rear axle?

Are you still on the stock front anti-roll bar or is it upgraded?

Cheers!

 

Answers:
[ul][*]Running 5zigen FN0r1-c 18x9.5 45mm offset with BFG g-Force KDW 275/35ZR18 on all 4 corners at 30 psi[*]+0.10 toe in, Camber -1.5, Caster dunno - told them to set it to stock specs. I was looking for something I could drive around everyday and not change for the occasional auto-x. Perhaps this is unrealistic?[*]Vogtlands came in a box with the same part number as what I ordered and everything looked factory packed/sealed(?). That being said -even if there was no funny business - maybe not the greatest choice? The car exhibits minimal braking dive and settles quickly from any change in attitude. I do like that part. I can feel every pavement snake and rock - don't mind that too much.[*]The LCAs are pointing slightly up toward/on the axle end. I have some relocs but have not installed them.
Still on the stock front bar. Stock end links on everything as well.[/ul]
If we could come out of this with a list that says, "try this first, then this, etc." that would be most helpful. Not afraid to hear, "you need to switch part a for part b" as long as it is backed by sound reasoning. Also not afraid to hear. "that's as good as x gets. If you want more buy an Evo [:'(]".


Was my first time racing and I was running low 62s. The guys in my class that won were running 58 on race rubber (17x9 Enkei wheels with 35mm offset). I absolutly know I was totally outclassed in driving skills (going to SCCA school weekend after this) but puttering with the car setup gives me something to do in the meantime... Hopefully I can pick up some additional tech advice there too.

Thanks!

 

Sluggish slaloming can usually be blamed on the shocks if it's a "parts" issue. Either they're not up to the job (which I really doubt in this instance) or that the adjustments are 'off'. Try experimenting with the rear shock setting relatively stiffer than the front. That should "loosen" the transitional behavior.

But how the driverattacks the slalom also matters- are you "getting behind" each cone? IOW, as you pass it are you already aimed in a direction to cross the slalom centerline or are you still trying to get the car back to straight from the previous maneuver? Reacting to each individual cone placement as it suddenly appears up close is a common driver "error".


If I'm interpreting 'S/C' correctly, you have more weight up front, which will tend to increase the amount of understeer over what a NA GT would have, everything else being the same.

Another strong possibility is "overdriving". Every tire has a limit as to how fast you can crank in steering input. Exceed that rate and it will simply start to slide. Especially if you're not completely off the brakes. At this very early point in your auto-X experience, more seat time will benefit you by more than everything else put together.


Norm

 

I agree on the dampers - they are probably good but may benefit from some setting adjustment. Another thread I've been reading also suggested bumping the front tire pressure. The car doesn't 'wallow' like it did before the suspension work, it just doesn't seem to turn fast.

If anything I feel ahead on each cone (trying to cut it too early.) the couple I took down over my 5 runs will attest to that. However, I do know a couple times I was carrying too much speed into a turn.

More seat time coming. Just want to make sure it's the right kind of seat time where I'm not reinforcing bad habits. Having done a couple other things in life (e.g. being a private pilot) I understand the importance of practicing the right way.

 

You have plenty of camber, more is better but -1.5 is a very good amount. Set your rears at a 1.5 turns off of soft; thatmight help. The stock front sway bar has a ton of preload. I bought a set of adjustable front sway bar end links from Sam Strano. (www.stranoparts.com) I haven't messed around with them too much, just installed them at the length they were at out of the box and they eliminated a lot of that preload, the car turns in a lot better now. You could also zero out your toe, that will help your turn in for autoX. I had mine set to zero yesterday, I hope to see how it works out this weekend.

 

I just sent Sam an order for those end links. Maybe he'll get on and comment (although I know he hates the email/message board thing).

Will do on the rear shock setting. What do you set your struts to?

Is zeroing out the toe going to be an issue to with high speed stability when I'm *not* autoXing? Let me know how you come out this weekend!

 

On the street I have mine at full soft, no reason to run them stiff if I am not racing on them ya know. When I raced I think I had my fronts at 1 full turn with the rears at 1.5 turns, all off of soft. I have only ran once so far this season, weather is still spotty here in Jersey.

With your toe set to zeroit can get squirllyon the highway butI didn't find itthat bad this morningon my commute in. Iam just keeping it in the back of my mind, beingcautious ofhow my car is setup and how it reacts as compared to every other car on the street. Keep a normal "at the speed limits" driving and I don't think it will be a problem. LikeI said I just had it setup yesterday and drove it this morning to work, I will try to gage a better interpretation of how it is during mycommute home tonight.I think with the struts set at full softis what may be helping it not feel as squirlly.Right nowit is probably the most neutrel feeling driving car I have ever owned.