Driving your GT3!

[Digga]

hunter 66 said:

EVO triangle

Enjoy whilst you still can and the limit is not 50 mph. Looks like they are doing a "Cat & Fiddle" with the A543: https://www.dailypost.co.uk/news/north-wales-news/...

[short-shift]

Porsche911R said:

Always up for a meet, but next Saturday is the opening of caffeine and machine in Stratford,

Good excuse for a sat drive out and in 6 days :-) should have my Ti bypass on by then.

Interested to hear whether you got your bypass fitted (it's a JCR, I think?) and what your initial impressions are. Maybe have a listen to it at C&M, if you're happy to say what time, roughly, you're likley to be there on Saturday?

James

[Porsche911R]

short-shift said:

Interested to hear whether you got your bypass fitted (it's a JCR, I think?) and what your initial impressions are. Maybe have a listen to it at C&M, if you're happy to say what time, roughly, you're likley to be there on Saturday?

James

slogged over it last night and it's on

it's insane :-) no drone from the short drive so far and driving like normal seems the same ish but you can tell it's on, then you WOT and the car is pure race car lol startup is crazy loud, not sure why the GT3 wants to wake the dead on start up flaps open..

took 2.5 hours but would be faster 2nd time round and if I had one extra tool for one bracket grrr that took 1/2 an hour to sort another way.

I have before vids just need to do after vids today. C@M is after 12 noon I think I aim to be there at the start ish., every GT3 needs a bypass , I Loved my GT4 sound and felt the GT3 lacking the excitement , but not now. just the geo to sort now.

I weighed the unit 3.6 lbs lol it's crazy light. the old one was 19.2 lbs with brackets

new brackets I did not weight (aggg) but it's 4 ring clips I would say 1.5 lbs for the new fitments so 5.1 lbs vs 19.2 .

13.5 lbs off the rear of the car behind the wheels is an extra bonus, plus the extra BHP and Torque you get with one.

I also fitted the RS air intakes as they are uprated hi flow over the stock GT3.

Funny how the RS had expensive hi flow filters and the GT3 did not. after a big of digging the extra BHP only comes from the RS ti system and filters, so I should have RS beating BHP as I also gain 15 bhp from the Manual tranny over PDK at the wheels.

I have other RS Sus parts going onto the car soon, so it should be as close to a Manual RS when done.

the systems is KS TI-1.2 ASNEX what ever that is, but sounds good if you google it :-)

[short-shift]

Thank you! Sounds very interesting. I suspect that C&M will be rammed over the weekend but I'll be there and I'll try and look you up and, hopefully, have a listen to your car.

James

Edited by short-shift on Friday 26th October 09:36

[short-shift]

Porsche911R said:

I should have RS beating BHP as I also gain 15 bhp from the Manual tranny over PDK at the wheels.

And also to chat about your claim that the MT gives a circa 15bhp gain over PDK; thats about, what, a 3-4% efficiency gain? I don't see that the parasitics in the PDK would come to anything like that. I'm interested to talk that through and hear where that figure has come from!

James

[Porsche911R]

short-shift said:

And also to chat about your claim that the MT gives a circa 15bhp gain over PDK; thats about, what, a 3-4% efficiency gain? I don't see that the parasitics in the PDK would come to anything like that. I'm interested to talk that through and hear where that figure has come from!

James

not a lot to talk about on that claim, bar if any one has a RS I'll drag race them at a Vmax event. I would like it to be a steel disk oem RS if any one wants to feature in a vid of that race.

PDK has a loss over a manual, what that is is hard to tell/find out, all my info comes from dyno plots from the USA and watching drag racing with people who want to find out for a laugh/fun.

5bhp,10, 15 no idea but you get more BHP to the wheels in a Manual that's proven and even talked about with AP.

I cannot tell in the seat 10 or 20bhp from 500bhp so the only way to is a race at Vmax.

I am just making the car the best it can be with OEM RS parts and a few aftermarket bits as I love the car to bits, it's every thing I wanted from my GT4 and more, so worth the effort making something a bit more bespoke.

[short-shift]

No worries; I can see that PDK will be marginally more efficient than MT but I would be surprised if it's of the order you mention.

But, that said, it's really your bypass that I'd like to hear - and your thoughts on it. You mentioned it was very loud on start-up but I assume that's with the valves open (so more or less straight-through from cat to tips)? Is it still 'neighbour friendly' on start-up with the valves closed (with the side mufflers in play), or too early to say?

James

[Taffy66]

short-shift said:

And also to chat about your claim that the MT gives a circa 15bhp gain over PDK; thats about, what, a 3-4% efficiency gain? I don't see that the parasitics in the PDK would come to anything like that. I'm interested to talk that through and hear where that figure has come from!

James

A Manual has about 15% parasitic losses and a good dual clutch has about 16-17%..US guys have dynoed PDK vs Manual and at full revs only between 5 and 10HP between the two.

[Porsche911R]

short-shift said:

No worries; I can see that PDK will be marginally more efficient than MT but I would be surprised if it's of the order you mention.

But, that said, it's really your bypass that I'd like to hear - and your thoughts on it. You mentioned it was very loud on start-up but I assume that's with the valves open (so more or less straight-through from cat to tips)? Is it still 'neighbour friendly' on start-up with the valves closed (with the side mufflers in play), or too early to say?

James

the flaps open on a GT3 at startup anyway, now it cracks and is a much louder statup.

just been out in the car for a go, it's mental, the car pulls and pulls till you run out of bottle. lol it did that anyway, but with extra noise it gets to you more.

I would do my after vid now but my next door nabour is on nights and got in a 6am so is asleep, so I'll do the after vid a bit later.

I have a pro level mic fitted to a SLR and will do both tests at 1 meter. but you cannot rev a GT3 more than 4k when not moving. ( I think)

In car above 6k it now has a race car feeling.

my car does nasty vibrating noise some times but it did that before, not sure if it's the cage or the passenger seat atm and some time it don't do it and some times it does, I need to locate that and add some matting to what ever is causing that.

no drone with the bypass though which is great news.

I am not sure it would be for every one and some might like the silenced by-pass more, I think JCR is the 1st to offer a pipe which has a silenced section on the PSE off part, so a bigger difference when PSE pressed between the 2.

Edited by Porsche911R on Friday 26th October 10:46

[short-shift]

Taffy66 said:

A Manual has about 15% parasitic losses and a good dual clutch has about 16-17%..US guys have dynoed PDK vs Manual and at full revs only between 5 and 10HP between the two.

Well, I can agree with these differences in outputs between MT and PDK but I'd question the percentage losses you've mentioned.

I'd expect a good MT to have around 4-5% efficiency loss, overall, and a good wet-clutch DCT (PDK) to be marginally inferior due mainly to the need for on-demand actuation/pump losses and pressurised, rather than splash, lubrication. Maybe an additional 1-2% of losses in total, so in the range 5-7% of overall efficiency loss for the complete transmission. This would indeed equate to a difference of around 5-10bhp between MT and PDK at the output of the transmission if the input is rated at 500bhp.

Incidentaly, a conventional planetary gear/torque converter automatic transmission might have overall losses and inefficiencies of around 10%, and quite possibly more...

James

[Porsche911R]

Taffy66 said:

A Manual has about 15% parasitic losses and a good dual clutch has about 16-17%..US guys have dynoed PDK vs Manual and at full revs only between 5 and 10HP between the two.

10 is 10 :-) if I have gained 15/20 with my current mods it should be a bit faster than the non RS PDK cars now.
once my brain can get into flat shift mode mind you as I still do a lift ! that's a >million miles of driving for you over 33 years !.

[Porsche911R]

short-shift said:

Well, I can agree with these differences in outputs between MT and PDK but I'd question the percentage losses you've mentioned.

I'd expect a good MT to have around 4-5% efficiency loss, overall, and a good wet-clutch DCT (PDK) to be marginally inferior due mainly to the need for on-demand actuation/pump losses and pressurised, rather than splash, lubrication. Maybe an additional 1-2% of losses in total, so in the range 5-7% of overall efficiency loss for the complete transmission. This would indeed equate to a difference of around 5-10bhp between MT and PDK at the output of the transmission if the input is rated at 500bhp.

Incidentaly, a conventional planetary gear/torque converter automatic transmission might have overall losses and inefficiencies of around 10%, and quite possibly more...

James

that's easy to see/find out as all USA dynos figures quote the wheels bhp and we know the flywheel , I am off to work though, but USA always quote wheel BHP and there are 100's of dynos for GT3 PDK cars.

[short-shift]

Porsche911R said:

the flaps open on a GT3 at startup anyway, now it cracks and is a much louder statup.

Yes - but I guess it's a bit more complex that that. I know that the valves/flaps are open momentarily on start-up because there is insufficient engine vacuum to close them (takes just a second or so...) but thereafter, with PSE "off", the valves remain closed at idle - sometimes an important factor for neighbour relations!

(And with PSE switched "on" the valves are always open at idle, then they close on driveaway until around 3,700 rpm and then they open up again).

Looking forward to hearing it!

James

Edited by short-shift on Sunday 28th October 08:24

[Taffy66]

Porsche911R said:

10 is 10 :-) if I have gained 15/20 with my current mods it should be a bit faster than the non RS PDK cars now.
once my brain can get into flat shift mode mind you as I still do a lift ! that's a >million miles of driving for you over 33 years !.

Between the JCR bypass and the BMC/K&N high flow air filters i think your GT3 could have the most WHP in the UK..Now how about some ultra light wheels such as BBS Fi-Rs or HREs R-101 LW. plus a Li ion battery for the ultimate GT3..

[Porsche911R]

Taffy66 said:

Between the JCR bypass and the BMC/K&N high flow air filters i think your GT3 could have the most WHP in the UK..Now how about some ultra light wheels such as BBS Fi-Rs or HREs R-101 LW. plus a Li ion battery for the ultimate GT3..

It's all coming inc. RS SUS parts :-)
BBS Fi-R, liteBlox battery, RS sus items, a very focused geo and some graphics which might split opinion !!!

Can I goto work now :-)

[TDT]

Porsche911R said:

Taffy66 said:

Between the JCR bypass and the BMC/K&N high flow air filters i think your GT3 could have the most WHP in the UK..Now how about some ultra light wheels such as BBS Fi-Rs or HREs R-101 LW. plus a Li ion battery for the ultimate GT3..

It's all coming inc. RS SUS parts :-)
BBS Fi-R, liteBlox battery, RS sus items, a very focused geo and some graphics which might split opinion !!!

Can I goto work now :-)

What RS suspension parts you planning?

[Steve Rance]

In response to the OP. This is why I think that the 911GT3 is one of the best ranges of GT cars ever built. The car on the left is a relatively practical and extremely rewarding road car. The one on the right is an incredible track car and equally rewarding (if a little more ruthless with it's driver). Incredible that they share essentially the same DNA.

Amazing cars

[Juno]

Steve Rance said:

In response to the OP. This is why I think that the 911GT3 is one of the best ranges of GT cars ever built. The car on the left is a relatively practical and extremely rewarding road car. The one on the right is an incredible track car and equally rewarding (if a little more ruthless with it's driver). Incredible that they share essentially the same DNA.

Amazing cars

Nice,Very Nice

[J.M.T]

Picked up my first GT last week after spending the last 12 months in a 718 Cayman S.

Oh my I love it. Cant wait to use it properly.

[Dblue]

Probably up for this as its a great venue in the middle of some epic roads.
Usually prefer a Sunday but this is good for me

(997.2 GT3 is the entry ticket in my case )