Jrtaylor9

Not sure what you'd be disagreeing with. My post doesn't offer any opinions, only questions.

STG

Didn't mean to start an R discussion with the video. Just thought it was cool to see a candid amateur video.

Would rather discuss options and info on the .2 GT3 here rather than compare it with other models, discuss pricing, allocations, values, worthiness of ownership, and all other subjects we already have threads for those things.

Sean in Texas

There is not. AP says in the introductory DriveTribe video that the SMFW will end up damaging the bearings when mated to this engine.

Waxer

Hydraulic lifters self-compensate for valvetrain clearances for maintenance-free service. Travel in the hydraulic mechanism soaks up variations in production tolerances and self-adjust to zero lash. They are also quieter than solid lifters.

A lot of performance cars, in fact I believe the vast majority of modern performance cars come with hydraulic valve train motors including the previous generation GT3’s with the Mezgers. It was only in race application that PAG used solid lifters historically. Other examples of hydraulic valved performance street track cars… all 997’s, all 991’s., GT4, all Boxster’s and Caymans, Ferraris back to the late 355s, Corvettes, Lambo’s, Mac’s, R8’s, AMG GT and AMG GTR, Vipers, M3’s and M4’s, GT350s, :’17 Mustang GT4, Boss 302 (‘12& ’13) including the R and S.

As you increase engine rpm limits or require higher rpm limits hydraulic valve trains reach their limitations. This is because under the stresses of high rpm, the hydraulic piston, which serves to zero-out the clearances in normal operation, can either pump up or bleed down.

Solid lifters are as the name implies-solid. There is no internal mechanism to take up clearance, and in fact, they require clearance to operate properly. This clearance is called the valve lash. As the cam comes around to the base circle, the lifter must unload the valvetrain and allow the valve to close. This occurs at zero lash, but some additional clearance is needed to give the solid-lifter valvetrain a little wiggle room to compensate for dimensional changes due to heat expansion. Lash is adjusted with wear or as setting fall out of adjustment. However, as RPMs rise so does valve spring pressure requirements leading to potential wear.

Go to minute 4:13.


It's not that solid lifter engines are "better". They are capable of reaching higher rpms due to lack of hydraulic issues but on the down side require higher pressure springs to compensate for the higher rpms leading to potential earlier wear.

The current .2 GT3 4.0L puts out the same performance power specs as the .1 4.0L with a 400 rpm higher red line. In my mind not that much difference.

They were running the GT3R in 2015 with the street RS motor beginning in 2015. This from PAG web site:

Powering the new 911 GT3 R is a cutting-edge four-litre flat-six unit which is largely identical to the high-performance production engine of the road-legal 911 GT3 RS. Direct petrol injection, which operates at pressures up to 200 bar, as well as variable valve timing technology ensure a particularly efficient use of fuel. Moreover, the normally-aspirated engine offers significantly better driveability and a broader usable rev range. Power from the rear engine is transferred to the 310 mm rear wheels via a Porsche sequential six-speed constant-mesh gearbox. As in the GT road-going models of the 911, the driver changes gears via shift paddles conveniently positioned on the steering wheel.

Engine:

◾Water-cooled six-cylinder boxer engine (rear mounted)
◾4,000 cm3; stroke 81.5 mm; bore 102 mm
◾Output: over 368 kW (500 hp) subject to FIA BoP (air restrictor)
◾Four-valve technology
◾Direct fuel injection
◾Dry sump lubrication




Also, ths from Car & Driver in 2015:

Just like its predecessor, the GT3 R is again powered by a 4.0-liter flat-six engine shared with a production model. In this case, the engine donor is the epic 911 GT3 RS, meaning the GT3 R gets direct fuel injection, dry-sump lubrication, and at least 500 horsepower. That muscle is routed to the rear wheels via a six-speed sequential transmission and a mechanical limited-slip differential, and racing-specific anti-lock braking and traction-control systems help keep things in check.

This from Autoweek May 2015.


We suspect the naturally aspirated 4.0-liter six-cylinder boxer engine out back, good for “over” 500 hp, sounds glorious as well. It’s the same motor you’ll find in the 911 GT3 RS. There’s no manual option -- just a sequential six-speed constant-mesh gearbox -- but we can’t complain, for once, because shaving fractions of seconds off lap times is this car’s raison d’�tre. Power is channeled to the rear wheels through a mechanical limited-slip differentia.

Read more: http://autoweek.com/article/car-news...#ixzz4b30WhN9n


So it appears that the hydrraulic lump did see competition and it would appear that PAG switched at some point to solid tappets used in the RSR for the Gen 2 "G" openning the door to even higher rpms in the future as the .2 now reves to 9000 where as the 2015 GT3R red lined at 8500 rpm and the current GT3R and Cup still interestingly red line at 8500 rpm. Perhaps PAG feels that they can get away with stiffer springs on the street version due to the fact they likely will not be seeing the constant and extended higher rpms of the race versions thus the stiffer springs are not an issue with premature wear.

Further, and importantly hydraulic valued motorsport heritage for the 9A1 DFI engines is also established by the GT4 Club sports which use the 991S 3.8L lump now competing in the Continenntal Sports car series in GTS. Our own CJ Wilson is campaigning a pair of GT4s.

signes

^ Nice summary 👍🏻

Thought the GT3R didn't have variocam

Guest89

I think it will come later. They can/will engineer a new lwfw for this engine, maybe in another application. A regular GT3 has never had a lwfw in the past. All 997 RS had them standard though.

bronson7

Waxer, thank you for taking the time and effort to post this.

MEM82

Im sorry if this was reported earlier, but do us cars all have the roof wart because satellite radio is standard?

ervtx

If you like the black door handles, don't let anyone tell you that it's in bad taste. It's a classic look.

squid42

The forward thigh support is different, it is short on the 4-ways. I think you can adjust the 18-ways to where the 4-ways are if you want to. If long thigh support is important to you you might want to confirm what's going on.

As another note, at least since last year the Cayman/Boxster carry different versions of the 4-way sports seats plus. So if you are at the dealer you can't use that as a reference.

Chris3963

Why lament the lack of a LWFW if the engine doesn't need it. AP in the Drivetribe video specifically says that the new enigine is so snappy from low revs that it is not needed.

Alan Smithee

^ AP is a salesman. What he actually said to PH was, "So the new engine with the single-mass flywheel up to this point in time is not possible."

I'm sure we will see it eventually, either on this or another model...

WildBill

Probably saving it for the 911R.2 or LE MT RS at the end of the run.

Alan Smithee

^ My money is on the former; perhaps on a Speedster version as well. I do think the RS will remain PDK.

Chris3963

And what he then said in the Drivetride video was that "the engine was so responsive and snappy that you won't miss it".