johnsopa

So, when I'm on the track and braking hard from high speed, say at the end of a straight preparing for a sharp turn, I row through the gears on my GT4. For example, if I'm in 5th going to 3rd, I'll push the clutch in then downshift from 5 to 4 then to 3. Clutch is kept in while doing this. The GT4 has always blipped throttle with each downshift.

I found with my .2 GT3 that it doesn't seem to do this consistently. In the example above, it sometimes feels like it didn't blip for 4 so then I will delay releasing the clutch when I get to 3 thinking that something happened. At which point the rev match probably times out and it doesn't work for 3.

Does sport mode/rev match work any differently for the GT3 vs the GT4?

Jimmy-D

What i have noticed is that it certainly hold revs with a much more pronounced feeling than the GT4 but may be necessary for a faster revving engine where revs would/could fall off quicker during up shift.

But also - the rev matching is different than in the GT4 but i can not really describe all the differences except the obvious I stated above

Wild Weasel

The gearing is different between the two cars. I'm wondering if your timing is off.

Note that if you shift too soon such that you're still going too fast for 4th when you put the stick there, it WILL NOT rev-match. Think of it as a nice warning not to let out the clutch. If you pull it out of 4th and put it back in (and you're now going slow enough) it WILL rev match. Then you're good.

What might be happening is that you're shifting too soon and haven't braked enough. So when you grab 4th you're still too fast but by the time you get to 3rd you're slowed enough so it rev-matches.

Is there any value in going through gears you're not going to use? Just curious there. I don't do that.

johnsopa

This was happening at much less than max revs. I'm early in break in so my self imposed redline was 6k.

I've been downshifting like this for years and I think it has helped keep me from ever money shifting, even when racing. Never had an over revs either, including zone 1s.

I'll see if this keeps happening in the future. If it does, I might have Porsche look at whatever sensor it is that tells what gear the lever is going into.

ajag

I'm still getting used to it, but there is definitely a big diff compared to the GT4. The blip is not as immediate on downshift, which was a bit strange at first but I got used to it. I also do downshift through each gear coming to a stop on the street, and can do this lazily in order to let it rev match each (clutch in the whole time), but I haven't tracked it so cannot comment on what happens when you do quick successive downshifts without giving time for rev match. Again, not sure the need to go down each gear, as Wild Weasel has said, I just do it on the street because it feels good lol.

johnsopa

Ajag, what you describe might be what I'm experiencing. Why would the rev match be slower than the GT4? That doesn't make any sense to me, unless maybe the GT3 engine revs faster so they program it to start the blip later compared to the GT4?

Jimmy-D

Remember - GT3 redline is 9000 and GT4 is ~7400. You are only touching the surface during brealin so can have some thing to do with it

Wild Weasel

Sure, but this should mean he's never outside the range he's trying to shift to and it should work flawlessly every time. I'm curious as to what he concludes from this.

Jimmy-D

He is saying he is keeping the clutch in and not letting out while dropping through gears. This could have some thing to do with it??

Wild Weasel

It shouldn't. My Boxster would just rev-match whatever gear you put it in. You could be coasting with the clutch in and put it in 3rd... neutral... 3rd... neutral... 4th... neutral... 3rd... and the noises could be hugely entertaining as it matched for every gear you put it in.

ajag

I don't know why the rev match blip has a slower onset, just figured it was working as intended based on differences between this and the 9A1 engine in the GT4, but maybe that's not the case?

ajag

I don't think so, I get the delay with any downshift, not just multiple gears with clutch in. I wouldn't think anything of it had I not experienced the quick blips of the GT4.

Wild Weasel

That does sound odd to me, but I've got no experience at all to compare it to. I've only ever driven my Boxster GTS with the rev-matching.

CAlexio

Car is in Europe for now so I can't test it, but I remember it feeling very different than my spyder, and not in a good way. From memory, I remember thinking that the rev match was initiating way faster on the gt3 (seems to flare revs just by touching the clutch) but then I'd try to row down through the gears quickly without letting out the clutch (6543) for example.. and it was strangely a lot slower than the spyder.

With the spyder it was more intuitive.. it would only flare revs (rev match) once I was already going towards a defined gate in the transmission, and then I could just keep the clutch in and bang down through 2-3 gears and hear it go "vroom-vroom-vroom" in quick succession.. with gt3 doesn't happen. It's definitely feels like a different setup. Not bad.. but spyder was more intuitive.

Wild Weasel

You're describing exactly what I recall from my Boxster. Strange that the GT3 is different. I mean... it was perfect. Different would have to be less than perfect.