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The answer is NO, Porsche held off on their promise to offer all models of their cars in all markets almost as soon as they made the promise.
Just like when we didn't get the RS 2.7, RS 3.0, 964 RS and 993 RS variants, we don't get the GT3RS.
I have a copy of the Porsche "Service Information Technik" on the GT3RS and here are the differences between RS and standard GT3 I find:
1. Engine has "optimized geometry" of intake ports and is designated M79/80 type number
2. The data record in the ME 7.8 Motronic is designated as "GT3 RS EU4" for programming of the control unit
3. There is a modified air duct below the rear wing on the engie cover to provide a ram effect at high vehicle speeds
4. The exhaust pipe tips are the same as the 40 years 911
5. Spark plugs are special M12X1.25 thread with 2 earth electrodes
6. The G96/90 gearbox is the same as normal GT3
7. Single mass flywheel fitted instead of dual mass
8. The RS front wheel carrier is completely different and is a hollow cast aluminum part and has 2 bolts instead of one to secure the strut, also has 6 bolts instead of 4 to hold in the wheel bearing. The mounting points for the control arms and track rods have been lowered relative to standard GT3.
9. A picture of the rear spring strut is shown in the book where I would expect the front strut to be shown and the text states that the spring rate is 45 N/mm which is what I would expect a front spring to be. There is not other mention of spring rates or other shock spring comments.
10. The RS rear wheel carrier is also completely new and is also a hollow sand casting with lateral and tie rod mounting points lowered as in the front wheel carrier. The wheel bearing is held in with 6 bolts instead of 4 here as in front.
11. The rear lower control arm has shims to adjust camber like the front and the eccentric to adjust camber has a longer travel so the slot for it is wider on the center carrier.
12. The stabilizers are same as the normal GT3 just set harder at the factory.
13. Carbon fiber front hood painted on top only inside is carbon look Only one gas strut to support.
14. Larger carbon fiber rear wing (7 inchs more span and 2 inches more chord).
15. Carrara White color only with choice of red or blue emblems with matching red or blue wheel centers
16. The front bumper cover has slots at the top which duct the center radiator upward rather than down under the car, wire mesh grills are fitted in front of the air intakes and at the outlets.
17. Polycarbonate rear window.
18. Carbon look rear view mirrors
19. Red or blue seat belts to match exterior logos.
20. Interior as GT3 clubsport but with Alcantara steering wheel, gear lever and handbrake sewn in red or blue to match logos
21. No glovebox
22. No cupholders (YES!)
23. Door panels with storage pockets instead of loudspeakers.
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