Westcoast

Great effort, but I was not suggesting that this measurement was the definitive measurement as to the wheel and center, it was more as a comparison between the two cars... eye balling it from a picture is far less accurate then any measurement.

Again, I asked but no one has offered up the official way to determine (on these cars) how to determine when the wheel is centered, I suspect it is NOT a measurement to the body or bumper! Although I am sure that this is part of the alignment process and can be determined when on the rack.

Westcoast

That's the spirit, and seriously we are just trying to better understand this setting and it's effect! T

Regarding the range, I checked with a Hunter rep and this is for the 2019-2020 718 Spyder, also look at post #21 in this thread by Croc999 and he said the spec from that Hunter sheet read what was shown there, pretty much the same.

KBS911

Good catch. Yes, the spacers were part of my rationale for not running the .5 variance that is usually noted, although I believe the DSC chart shows different F/R as well .Can really feel the difference with the spacers up front. I am new to the GT4 platform and am feeling my way through the handling characteristics as I go. At my first AX the *** end felt quite loose early on, but I attribute some of that to the Dunlop tires that don't seem to heat up as quickly as the Cup 2's I have been use too.
I am tiptoeing my way through the alignment adjustments to achieve an overall balance so I'm looking forward to Sebring this weekend to see how it performs at the track. The good thing is I'm only an hour away from BGB and they've forgotten more than I'll ever know about tuning suspensions. It's great to be able to work with them, describe what I'm feeling in the car, and having them adjust accordingly. I'm sure I will tweak some more before I find the sweet spot. Baby steps as I learn the car.

lovetoturn

Thats how you do. Try an initial set up, drive it, return to guys like BGB with your feedback and they will tell you what to adjust next. Repeat cycle as needed to get the desired results. Just going to your local dealer and assuming they know how the cars drive on the track doesn't always work so well. You need to have a mechanic who races cars himself and or knows a lot about the whole process. I am very lucky. I have that guy here in Dallas.

phefner

Great thread guys. I'm getting ready to bring my GT4 in to swap snows and prep for the tracking season here in the midwest. One of the tasks is an alignment and 4-corner balance. Is there some preferred setting on the anti-sway bars? I haven't seen much in the way of discussion on sway bar adjustments, and being a relative track ***, was thinking of starting out with the OEM alignment, and setting anti-sway bars to stiffer rear and, and stay with the OEM middle setting on the front. Moving the rear to more stiff should also help reduce body roll, whereas targeting a softer front might induce body roll. Then do some lap days; on my next set of tires look at more sway adjustments, then look at some toe, then camber, etc...repeat.

Road America isn't too far away and I like to get in 4-6 weekends there each season.

Reasonable approach?

KBS911

Just to update. Got back from Sebring last weekend. First time on track with the GT4. Car handled great. Slow start as I learned the car and only ran on Friday, but got down to solid repeat 2.28's without trying hard. Quite a bit of traffic at times. First session of 4 was a throwaway getting the Dunlop tires up to heat. Ran them at 29-30 front to 32-34 hot and they stuck well. The alignment at 2.2 F / 2.0 R, both bars in the middle worked well. Terminal speed at 17 was right at 140, 131-133 at 7. Car was perfectly stable under hard braking. Thank you BGB!! Wish I could have stayed another day. I think 2.25's and under will be easily attainable as the whole day was just getting comfortable with the car. I will be changing brake pads to Ferodo 312's as the stock pads seemed to lack initial bite. My car has 18 way adaptive seats and I had a good bit of arm/chest pump at the end of the day after hanging on. A Sparco QRT leather performance driver seat is on order along with Schroth belts and BBI seat base and brackets. BTW, you will need the Sparco specific side mount brackets if you go this route. Went with the Competition Motor Sports roll bar with extra trim pieces. Anyway this car is a blast to drive on the street, track, and at AX and I'm having fun learning the car and researching and adding mods as I go. All items are on order and scheduled to be installed by BGB. Great folks with a wealth of knowledge on these cars!!

jwr9152

Had my first track day in my GT4 at Sebring in January with similar results. My first time at Sebring. I did have Ferodo DS1.11 but other than that it was stock. I also ran medium/medium on the sway bars and had no under steer. Car felt very neutral. I think I could get down to the 2.24s with a little more track knowledge. Great track and great car.

CaymanSinAR

Picking up my 718 GT4 in a couple of days. Plan to have it aligned next week. My primary focus will be autocross, but I might do a day or two here and there at Barber Motorsports Park and Hallett Motor Racing Circuit. And I'm sure I'll drive it on the road quite a bit too.

I know and understand zero about alignments and such. Zip, zilch, nada. Luckily we have a specialty shop locally that takes care of everything. That being said, if there are folks here that enjoy autocross and the occasional track day I'm all ears for advice.

For street driving and wet autocross/track I'll have factory size PS4S N0 on factory wheels.

For dry autocross I'll have F1 Supercar 3s on 20" Leggera HLTs. Factory width wheels with factory size tires.

For track I'll run Sport Maxx Race 2s on 20" Leggera HLTs. Factory width wheels with factory tire sizes.

I'm coming from a PDK 991.2 GT3 that was, admittedly, about as perfect as you can get for track and autocross. No issues with oversteer or understeer; just perfectly balanced. Had a 981 GT4 as well but did not spend enough time dialing it in before getting the GT3.

The best thing to do is probably let the local shop do what they do and don't worry about it. But again, if anyone here has advice I'd love to hear it.

dnimi123

Maybe not best to leave it up to a 'local shop' and Ill tell you why. There are groups and vendors here who focus on Pcars and the GT4. One is DSC Sport. IMO they have worked out a pretty good solution to fix the GT4's horrific understeer (and it is truly awful) and vicious tail wag - truly the car is a pig out of the box with terrible alignment specs from the factory. You are smart to want to get the car aligned right off the bat. However, Porsche limits the ability to get more aggressive camber settings than -1.8 front and -1.4 rear. This may be enough for you but I doubt it. Thus you will need a set of rear adjustable toe links and 10mm shims. I recommend TPC Racing toe link (along with the DCS controller) and get the shims from Mike at RSS. You should also set the Front sway bar at FULL SOFT and the rear sway bar at FULL HARD to complete the balancing of the car. DSC Sport has full alignment specs on this site. Do not lower the car - it doesnt need it. I disliked the handling characteristics of my GT4 until I followed this recipe (which many others also have) and now the car is 85% in the suspension department with no downside trade offs at all. The cost all in with alignment is about $2,500 and the best money I have spent on the car to date. God luck.

dnimi123

Im running the DSC recommended settings at FULL SOFT front and FULL HARD rear. Very happy with the way the car feels, especially after adding the toe links to get better alignment specs.

dnimi123

Spacers or shims? How did you get the -2.2 in the front without shims?

CaymanSinAR

I really appreciate your advice. I already have a DSC Sport since it was in my last GT4 and I kept it figuring I'd end up with another GT4.

Keeping in mind I said I know zip, zilch, nada about anything, would I need 2, and only 2, of the 10mm shims found here?

I'll do some digging for the alignment specs. What is on the DSC Sport site is a bit confusing.

SpyderLegend

For those with soft front / hard rear sway bars... how is that specific setting compared to stock? I am scared about less initial turn in response from soft front bar and less traction with rear hard bar. I don't have toe links, neither DSC, but I have -2° front camber and -1.5° rear. Sway bars still in middle setting. I don't track my car but I hate understeer.

Westcoast

My Spyder sway bars are in the mid/mid positions I don't notice any understeer...

KBS911

The spacers didn't affect camber. Needed shims to get the 2.2.