TrackDays247.com

GT4 tip: Never run a HIGHER friction REAR pad

Bill Lehman

Its well documented that substantial additional rear toe fixes rear stability issues under hard braking. You need rear toe links and about 3 mm per side. The LSD can impact this but when my GT4 was new with a fresh LSD, braking was an issue.

AutoquestMotorsports

Hypothetically sure, but you would feel the difference between a worn one and a new one. We've had cars with 10 track miles feel the exact same under hard braking as those with in excess of 20k track miles. Of 50ish GT4's we've serviced since their release, we have yet to have an LSD fail or perform differently from new to warrant replacement.

kfmcmahon

Tom@TPC Racing

Can stiffen the rear rebound via DSC. Email me I have a mapping with stiffer rear rebound during braking.
tchan@tpcracing.com

kfmcmahon

Ok sounds good Tom.

Warwick Morris

I think all GT4's wander a bit in the rear when braking at high speed. I have found coming onto the brake a bit softer and then increasing pressure helps quite a bit. I think it just lets the weight transfer to even out a bit. I also run the DSC controller and would look to upgrade the software if it helps.

aualexa2

Anyone else finding that OZ Leggeras bend pretty easily?

DC640

Camber plates and Elephan racing pucks in. Really made the different in adjustability

Camber F-3.5 R -2.5
Caster 9
Toe 1/16F. -3/16 R
Swaybar Soft/hard

I was able to fit 265/285 Re71r. Zero rubbing and wheels are nicely centered. See pic.

Before the camber plates and caster pucks, I was only using shims - caster was at 10.9 and camber at -2.8. Outside of tires got eaten up
Tires pics posted below.

BlackRain

AutoQuest Motorsports

Thank you for that update! It is great to hear Michiel's car is in good hands and in the environment he made it for

Dan991C4

Any recommendations on a GT4 harness bar and belt set up? I am looking at the "Agency Power Bolt in harness" or equivalent system.

I just traded my 991.1 C4 w/PDK for a GT4 and am very glad to be shifting gears again.
I will check search the other sections too for some instruction on bolting all the belts in securely.

Lots of good data here on setup - very cool!

ajw45

Congrats! If you are looking for a harness mount w/o a roof support the Brey Krause mounts are hard to beat:

https://www.bkauto.com/R_1046_Should...t_p/r-1046.htm

They mount behind the seats to the cross member so you don't need to run a separate bar which makes for a cleaner install and doesn't take as much room behind the seats. I installed mine with an additional custom roll hoop

Dan991C4

Very nice looking setup in your GT4 and thanks! I see Brey Krause has all the lap belt and sub-belt connection parts I need, My GT4 has the CF Buckets too so getting the seat to fully roll back for easy vehicle entry and exit was a concern.

*Which under-seat rail sub-belt connection option did you use? It looks like there are some options our manual seat slider used for the CF Buckets.

ajw45

I went with cantrell which are mounted to the seat frame and slide with the seat. I suppose the proper way to do it is mounted to the floor but then those points would need reinforcing etc.....

https://cantrellmotorsport.com/produ...ub-belt-mount/