Maybe my question should be keeping 2mm rear toe per side, how much rear camber can I achieve with shims only?

 

As you move out the LCA with shims you will run out of adjustment using the OEM eccentric bolt.....not sure of how much you can do without going with adjustable rear toe links as I never tried without them, maybe others here can chime in on this.

 

Anybody chasing larger camber numbers is likely going to the track, so upgraded adjustable rear toe links are a must. With that being said, The TPC toe links also reduce rebound toe out deflection which makes the car more consistent, stable, and safe. You don't want to go over a bump in a high speed corner at the limit, and on the way down from the compression have the rear outside wheel decide to add a mm of toe out for a moment. That can lead to a quick snap spin if you are not careful.

 

I want to do the toe link upgrades in time but I am new to tracking this car so one step at a time. Frankly I am alittle disappointed to hear Porsche build an amazing performance car only to have us buy a bunch of aftermarket parts to do a proper track alignment! I am not unfamiliar with tracking as my previous car ran -3.5 front and -3 rear. I am not sure if it is because of the suspension design.....but maybe a proper double wishbone setup is better?

 

That's apparently what Porsche decided on the 992 GT3

 

Regarding the heavy lift of the wheel + tire, an alternative to the mounting pin is to convert to studs. I installed Rennline's studs (the short studs are fine) and Tarett's "Nascar style" wheel nuts (very hard, will not deform with repeated impact wrench use). I autocross and DE my GT4, and 981 GTS, so I am changing wheels often. If that's your plan too I recommend studs.

Howard

 

Only the front suspension. I have a feeling it may be hard to parkage double wishbone for rear motor. I think the RSR race car is mid engine with double wishbone?

I love the new GT3 but it is out of my budget.

 

I saw your posts on some other threads but I think they were older than this. Did you get it back on the pads and what did you come up with?

Also, I want to do the Motorsport front camber plates to preserve castor but I haven’t been able to find how much camber they add vs. shims. I.e. with no shims and only the plates where does the camber land? That becomes my starting point. I want to do an aggressive street alignment but be able to dial in another degree or so for the occasional HPDE so if the starting point is more than a what we arrive on as an aggressive street number that becomes problematic.

 

At least with Tarret camber plates you get an extra -1 degree camber......

 

911s are multilink rear so not much problems as a strut design like on the mid engine platform.

 

Camber plates are nice, but you probably want some additional shims in front to increase the track. This will help with front end grip, and help reduce understeer.

 

Yes....but once you start crossing -2.8 negative camber up front with shims only you need to correct that caster either with camber plates and/or adjustable tension bars (or the LCA pucks with 3 position).
Another things is that if you do go for a 265 tire up front you need to tuck that tire inside the fender and also correct the caster or you will have contact with the front fender edge.
I do a combination of shims and camber plate but get most of the camber from the camber plate.
One thing that helps is that if you upgrade wheels for the track go for a 9" front.....the OEM is 8.5" (GT3 is 9")...you gain 0.5" there alone.

 

BGB’s “shop” GT4 is sporting 15mm front wheel spacers presumably partly for this reason. Once I get mine it will be interesting to see how many shims, if any, exist from the factory. I know they have been chasing a setup and perhaps the need for the plate won’t be there for my application, which is 90% aggressive street use, we will see. I only spent a few minutes with them last week and we didn’t get into specifics since I’m at least a month out from needing to get the work done between my delivery time and them finishing up with their Rolex support.

 

I will not be upgrading for the track, I might do one DE a year and maybe a few auto-x’s. I’m looking for the optimal street setup that can be tweaked for the occasional event. Getting the GT bits from the factory gets me 90% there but I’m not against fine tuning from there.

 

In that case sounds like you will be using the OEM 20" wheel/tires....good idea to go for more track and probably a max of -2.5 camber up front.
I'm pretty sure John will get you car setup correctly, very few people know the mid engine platform as well as the guys at BGB.