guab

Not sure a 4.0 with more normal internals would be less money than a 3.8 that's already completed full R&D cycle.

ExMB

The issues, as stated previously, may have more to do with the upcoming change of the EURO emission requirements in 2018. I read on here thats why most of the new GT3/RS production will have to be completed in 2018 and not run into 2019 (rumored GT4(RS) entry). Therefore it could be that the 4.0 might be easier to detune to meet, or come close, to meeting the emission requirements whereas the defunct 3.8 would require too much work.

spyderphile

I thought the new regs are kicking in 2020, as would be for motorcycles. They are supposed to clamp down on noise level as well. Did you hear anything about it? Engine/Exhaust notes are likely to be impacted. Most of the motorcycles (from MY '17) sound awful!

ExMB

Nothing that I can really put my finger on, that is verifiable. All is guess work now, educated extrapolation from posts on the GT3 forum. I mean that the overall level a company has to have might allow for a few that exceed but ..... I even thought that in Europe they were going to limit the sport exhaust (also known as SAGA) was on the table due to noise regulations.

gregp714

Fake news 😂

Sven76

In Europe, new emission rules kick in 3Q/2018, this will require significant modification of existing naturally aspirated engines. ROW will be a different story.

spyderphile

These days, regs from markets such as the Europe and the US have universal adoption. It makes the design, manufacturing, etc. less complicated, efficient, hence cheap. So, the new Euro regs will be applied across the board. I am most concerned about the expected restrictions on noise. The engine/exhaust notes will be adversely impacted. Let's see how Porsche plays it. We may have already seen the best of engine/exhaust notes.

MagicRat

Have faith. My '17 BMW S1000R sounds incredible and it's Euro 4 compliant. Does come with an Akrapovic can from the factory though but still. Regs don't have to mean aural misery.

Hams955

718 GT4 will be a 2019 release. 4.0L. The MR's won't make it in time for the 2018 season which is really unfortunate for PMNA as a lot of owners are jumping ship and moving to other manufacturers. PMNA has promised a car that WILL compete; just won't make for next season. The street car will be a 2019 MY.

- Chris.

d00d

The same engine as before, but with longer stroke aor bigger bore, or the GT3 engine?
Given Porsche's penchant for model proliferation, I had assumed there would be both a NA 7.8K 3.8 X51/4.0L GT4, and a NA 9K 4.0L GT4 RS.

ExMB

It would be too expensive to do 2 different engines for possibly 3 models. Assumption is a detuned GT3 4.0 engine for both the GT4CS and the GT4(RS) where the final nomenclature has not been settled on. Even if Porsche decides on 2 street versions it would be far easier and cheaper to differentiate them with a different tune than a different engine.

NoGaBiker

I heard they're putting the 3.8 Mezger motor in it, retrofitted for DI and using six mini-turbos, one hanging off each exhaust port. Can anyone verify?

spyderphile

Hope you are right. The only bike I know of that sounds good, with Euro 4 compliance, is RSV4. Let's hope Porsches, at least NA models, would continue entertain us with delicious aural notes for a few more years!

tcsracing1

the 781 GT4 will be normally aspirated which is great.

It would be easy for Porsche to keep the 3.8L but add the X51 package/throttle body to make it a true 991.1 Carrera S motor.
However, it might still not be enough to compete in GT4 racing for 2019.

A 4.0L version of the engine would be nice.
Although, i cannot see it being the GT3 motor due to cost.
That being said, In 2019, there will be no GT3 models available therefore a 4.0L is marketable in a 718 because I see no model crossover issues.
The Trouble with a detuned GT3 motor is it would still be more expensive then a 991.1 Carrera S motor...

Question is, can porsche still build a 991.1 Carrera S motor and bump it to 4.0L? Or would they really use the GT3 motor and detune it somehow?

I cant see Porsche letting the GT3 motor in the 718. It would be too close for comfort to the 911 GT3.

In 2019 i just cant see the GT4 Clubsport sharing the same basic engine format (detuned) as the 2019 GT3 Cup car.

If the 2019 GT4 is only the X51 package on the 3.8L, it will be fairly easy to install the same kit in the 2016/2017 GT4 Clubsports to keep them competitive.

Hams955

Deleted.