GT4 Clubsport with front through hood cooling at VIR
Note fascia exit blocked off as air passes through trunk and out the hood vents.


GTLM style rear diffuser installed, side view

GTLM style rear diffuser, rear view

The car has not been tested in the wind tunnel (yet), but was on track at VIR at the beginning of November, 2019. Compared to his last track event (August, 2019) without these aero mods, the driver felt slightly more high speed understeer, indicating the center of pressure has moved rearward due to the increased rear downforce. More testing scheduled in December at Sebring.

 

Do you also have the rear multi-link setup and if so, could you talk about the results? Thx.

 

Yes, this car has the Multilink rear suspension kit (there were actually 5 GT4's at VIR with the kit installed) and the drivers comment first on the improved high speed stability and increased rear grip. One of the driver's has both a GT3RS and a GT4, with rear multilink, and he prefers driving the GT4 on track because it is more fun to drive.

 

Thanks, do you know if anyone has tried to adapt the kit to a 987 yet?

 

The kit could be adapted to a 987, but would require modifying the 987 rear uprights significantly. Alternatively, you could put the GT4 981 multilink rear uprights on a 987 but then the halfshaft outer end spline is smaller (since the wheel bearings and hubs are smaller on the 987 than the GT4) and that would require GT4 halfshafts. So, the kit would be even more expensive for the 987 due to all the GT4 parts required to complete the conversion.

 

Good to know, appreciate it