Rev-matching
Thread Starter
Rennlist Member
Joined: Dec 2009
Posts: 77
Likes: 24
From: Richmond VA
Rev-matching
I have a lifelong (I'm 69) habit of double clutching and rev matching on downshifts. It is easy and correctly performed on all my cars (E90 M3, M Coupe, WRX, 997.1 GT3), but for some reason I can't seem to get it quite right on my newly acquired 997.2 GT3. There seems to be a short delay/disconnect when I blip the throttle. Without near-instantaneous response, which I am not getting, the downshifts are neither smooth nor precise.
Car has 23K on it and otherwise drives beautifully. Well executed rev-matched downshifting is one of pleasures of a manual, so I wish to address this. Maybe its me and I'll just become used to the new car, but this split second delay just does not feel quite right.
Is there anything mechanical or electronic that can be checked pertaining to this. TIA for any advice.
Mike
Car has 23K on it and otherwise drives beautifully. Well executed rev-matched downshifting is one of pleasures of a manual, so I wish to address this. Maybe its me and I'll just become used to the new car, but this split second delay just does not feel quite right.
Is there anything mechanical or electronic that can be checked pertaining to this. TIA for any advice.
Mike
Thread Starter
Rennlist Member
Joined: Dec 2009
Posts: 77
Likes: 24
From: Richmond VA
Thank you for response. Wish it wasn't so, very irritating. Please share any results. Maybe some others can share experience too.
Burning Brakes
Joined: Oct 2014
Posts: 1,195
Likes: 8
My 07 GT3 has no delays. No problems with throttle delay. Maybe the previous owner changed played with the ECU.
Rennlist Member
Joined: Sep 2009
Posts: 3,601
Likes: 431
From: Driver's Seat
^ Same here. Multiple generations of GT3 ownership, never had a single issue with any throttle lag. If anything the near-instantaneous throttle response is a key selling point of these cars...
ECU programming is the first suspect.
On the mechanical side, with PIWIS plugged in your tech can see how quickly the throttle butterflies are reacting to pedal input. Compare that to a known sample to determine if you have a "slow" throttle body. Then there are two butterfly valves inside the intake distributor that shape airflow across the rev range--doubt that's the cause of your problems but still a possibility.
ECU programming is the first suspect.
On the mechanical side, with PIWIS plugged in your tech can see how quickly the throttle butterflies are reacting to pedal input. Compare that to a known sample to determine if you have a "slow" throttle body. Then there are two butterfly valves inside the intake distributor that shape airflow across the rev range--doubt that's the cause of your problems but still a possibility.
Trending Topics
Rennlist Stories
The Best Porsche Posts for Porsche Enthusiasts
9 Features and Characteristics That Only Porsche People Understand
Verdad Gallardo
I've Written 500 Rennlist Articles: Here's How Porsche Has Changed Along the Way
Joe Kucinski
10 Most Unnecessary Porsches Ever Built (And Why We Love Them)
Verdad Gallardo
Porsche 911 GT3 S/C vs 718 Spyder RS: 10 Categories, One Winner
Joe Kucinski
This Builder Is Turning Heads With Its Slantnose 911 Creation
Verdad Gallardo
Porsche 911 GT3 Artisan Edition Pays Homage to Japanese Culture
Verdad Gallardo
Porsche Reveals Coupe Variant of the Electric Cayenne With a Fresh Look
Verdad Gallardo
10 Porsche Colors That Have More Personality Than Most People
Verdad Gallardo
Guntherwerks' Final Speedster Creation Is the Ultimate Porsche Restomod
Verdad Gallardo
Rennlist Member
Joined: May 2007
Posts: 3,086
Likes: 307
I have a 996-3 and mine is perfect, but it did come with a Lt Wt flywheel clutch kit. You may want to consider re setting the throttle. I know it can be done on the 6-3, not sure about the 7-3. Im not sure of the procedure off hand, but Im sure it can be searched for here easily enough.
Pro
Joined: Mar 2011
Posts: 705
Likes: 6
From: Rock Hill, SC, just south of Charlotte, NC
As one who has blipped the throttle on millions of downshifts since the mid '60's, I find the throttle response on our '07 GT3 just fine, so perhaps you can compare your car's response to others in your area to see if your perception is actual. As for a possible remedy if so, I have no idea how to correct the problem.
all the best....
NV
all the best....
NV
Burning Brakes
Joined: Feb 2009
Posts: 882
Likes: 8
From: So.FLa/MA
I too have been throttle blipping for years, not only in the GT3, but motorcycles, race cars and many P-cars
I Have never felt this delay, except in my wife's Audi A6 which is much worse.
I will be sending my ECU for a flash as they advertise this problem will be effectively gone. By virtue of them writing an algorithm to fix this, verify's this problem does indeed exist. It may not be prevalent in all cars, but there are a few issues with some cars.
My C2S was a dream to rev match, no delay.
I Have never felt this delay, except in my wife's Audi A6 which is much worse.
I will be sending my ECU for a flash as they advertise this problem will be effectively gone. By virtue of them writing an algorithm to fix this, verify's this problem does indeed exist. It may not be prevalent in all cars, but there are a few issues with some cars.
My C2S was a dream to rev match, no delay.
Rennlist Member
Joined: Aug 2013
Posts: 756
Likes: 305
From: Fort Worth