More power for the GT4 - any valid numbers?
#91
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Just an update. I ran in the event yesterday and did OK but my main straight best terminal speed before my braking marker was the same vmax of 223kph. It was a very hot day (38C) and the mods may have worker better if it was about 10C cooler but still, one could not say that it was a great result; I was hoping for circa 230kph top speed. Having now run in a few events at different tracks, I've reached the conclusion that the best upgrade for this car would be better tyres....The MPSCupIIs are just not in the same league as Yoko AO50's and one can only hope that someone will make a proper R-Spec tyre for a this car in a 20" sometime soon.
whats sort of times were you putting down with your current set up?
p.s. i have removed the swift springs, although the car was better before approx. 1-2 sec per lap on the GP circuit, i could not get it up the driveway...
#92
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Hi .dee, my speeds were 10 hz GPS and I've not seen over 223. We were running on the North circuit on Saturday in a BMW Club sprint event. My best was 1:11.98 and I came 6th out of 52. 5th was a 991 GT3RS with a 1:10.77. The top 4 were race cars. My best at the GP circuit on a track day with 100% stock was 1:47. The car is quite a bit slower than my old 996.1 GT3 which has run a sub 1:42 but it is what it is. I'm going to try some Trofeo R's which the Victorian guys say work well at PI and they did a good job at Bathurst last November. I am going to run the car in this year's PCNSW Supersprint series and it would be good to run against some other GT4's.
I'll stick with the TB and IPD for a while though it seems to add zero at present.....might be interested in your springs though if you want to PM me.
I'll stick with the TB and IPD for a while though it seems to add zero at present.....might be interested in your springs though if you want to PM me.
#93
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Hi .dee, my speeds were 10 hz GPS and I've not seen over 223. We were running on the North circuit on Saturday in a BMW Club sprint event. My best was 1:11.98 and I came 6th out of 52. 5th was a 991 GT3RS with a 1:10.77. The top 4 were race cars. My best at the GP circuit on a track day with 100% stock was 1:47. The car is quite a bit slower than my old 996.1 GT3 which has run a sub 1:42 but it is what it is. I'm going to try some Trofeo R's which the Victorian guys say work well at PI and they did a good job at Bathurst last November. I am going to run the car in this year's PCNSW Supersprint series and it would be good to run against some other GT4's.
I'll stick with the TB and IPD for a while though it seems to add zero at present.....might be interested in your springs though if you want to PM me.
I'll stick with the TB and IPD for a while though it seems to add zero at present.....might be interested in your springs though if you want to PM me.
I am going out on Wednesday morning with the CPC guys to get a few laps in before heading off OS, the only difference in the current set up to the earlier one are the rear offset toe links (allowing -2.0 Camber) and front (Medium) and rear (Hard) sway bars.
re: springs you can have them for 50% ($500) if you want
#94
#95
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My experience is not that great with modding my GT4. Currently have cargraphics race headers, IPD plenum, 82mm throttle and tune (Tune came with the package). Dyno at 368whp. Top speed on the main straight is within 2kph of when the car was stock (using aim datalogger). My conclusion is that the mods dont work.
#96
Drifting
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My experience is not that great with modding my GT4. Currently have cargraphics race headers, IPD plenum, 82mm throttle and tune (Tune came with the package). Dyno at 368whp. Top speed on the main straight is within 2kph of when the car was stock (using aim datalogger). My conclusion is that the mods dont work.
Hope you find the results you were looking for. GL
#97
Rennlist Member
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My experience is not that great with modding my GT4. Currently have cargraphics race headers, IPD plenum, 82mm throttle and tune (Tune came with the package). Dyno at 368whp. Top speed on the main straight is within 2kph of when the car was stock (using aim datalogger). My conclusion is that the mods dont work.
#98
Three Wheelin'
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Didn't shakenbake also post that his car with mods wasn't faster than a stock car on the straights?
#99
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No tune but the OEM ECU should be able to use the additional air supply. My conclusion at this stage is that best improvement for lap times would be to fit cup brake calipers and 18 wheels so that proper competition R-Spec tyres can be fitted, this would be followed by a higher FD.
#100
Race Director
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Originally Posted by Warwick Morris
No tune but the OEM ECU should be able to use the additional air supply. My conclusion at this stage is that best improvement for lap times would be to fit cup brake calipers and 18 wheels so that proper competition R-Spec tyres can be fitted, this would be followed by a higher FD.
#101
Rennlist Member
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Two areas of performance:
1. Peak performance/peak power (hp, top trap speeds, 0-60, etc)
2. Drivability, which can increase pleasure in use as well as cumulative speed
Sounds like BRNGT4 isn't seeing improvements in #1 to merit the expense. Sadly, that's par for the course with a lot of aftermarket gear. Whether or not a tune would improve his findings, I have no idea. I have been told by someone in the factory that the X51 plenum needs work to fit in the GT4 but does not need a tune to be taken advantage of. Still waiting to hear back about headers + plenum.
All a lot of speculation until there is better data.
Now, about area #2, driveability...that is much harder to document, but it can make ALL the difference. One race car can generate more g around a skidpad, and be lapped on track by a car with less grip in outright terms. This is true in every area of a car's performance...
1. Peak performance/peak power (hp, top trap speeds, 0-60, etc)
2. Drivability, which can increase pleasure in use as well as cumulative speed
Sounds like BRNGT4 isn't seeing improvements in #1 to merit the expense. Sadly, that's par for the course with a lot of aftermarket gear. Whether or not a tune would improve his findings, I have no idea. I have been told by someone in the factory that the X51 plenum needs work to fit in the GT4 but does not need a tune to be taken advantage of. Still waiting to hear back about headers + plenum.
All a lot of speculation until there is better data.
Now, about area #2, driveability...that is much harder to document, but it can make ALL the difference. One race car can generate more g around a skidpad, and be lapped on track by a car with less grip in outright terms. This is true in every area of a car's performance...
#102
Nordschleife Master
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Originally Posted by stout
I have been told by someone in the factory that the X51 plenum needs work to fit in the GT4 but does not need a tune to be taken advantage of.
#103
Race Director
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Originally Posted by stout
Two areas of performance:
1. Peak performance/peak power (hp, top trap speeds, 0-60, etc)
2. Drivability, which can increase pleasure in use as well as cumulative speed
Sounds like BRNGT4 isn't seeing improvements in #1 to merit the expense. Sadly, that's par for the course with a lot of aftermarket gear. Whether or not a tune would improve his findings, I have no idea. I have been told by someone in the factory that the X51 plenum needs work to fit in the GT4 but does not need a tune to be taken advantage of. Still waiting to hear back about headers + plenum.
All a lot of speculation until there is better data.
Now, about area #2, driveability...that is much harder to document, but it can make ALL the difference. One race car can generate more g around a skidpad, and be lapped on track by a car with less grip in outright terms. This is true in every area of a car's performance...
1. Peak performance/peak power (hp, top trap speeds, 0-60, etc)
2. Drivability, which can increase pleasure in use as well as cumulative speed
Sounds like BRNGT4 isn't seeing improvements in #1 to merit the expense. Sadly, that's par for the course with a lot of aftermarket gear. Whether or not a tune would improve his findings, I have no idea. I have been told by someone in the factory that the X51 plenum needs work to fit in the GT4 but does not need a tune to be taken advantage of. Still waiting to hear back about headers + plenum.
All a lot of speculation until there is better data.
Now, about area #2, driveability...that is much harder to document, but it can make ALL the difference. One race car can generate more g around a skidpad, and be lapped on track by a car with less grip in outright terms. This is true in every area of a car's performance...
But I challenge anyone with a regular spyder or gt4 to get into mine and not feel a massive difference from stock. 'UUGE difference from stock. Before it was strangled, now it's an animal. Smoothness, torque fullness, lugging from lower gears it just continues to pull all the way to redline, let alone the increased volume after 4K rpm. It has made the car immensely more enjoyable to drive. So.. even if it's only Stout's #2 which changes, I still have zero regrets and would redo it all over again, especially considering how easily reversible everything is. but I'd be really surprised if #1 didn't change also.
#104
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Working in the medical field, I'm all too familiar wth placebo effect.. human brain has a crazy way to make itself belief something it thinks it should believe. So maybe after we spend $ on mods we want to believe will work, then we actually feel them working. Maybe.
But I challenge anyone with a regular spyder or gt4 to get into mine and not feel a massive difference from stock. 'UUGE difference from stock. Before it was strangled, now it's an animal. Smoothness, torque fullness, lugging from lower gears it just continues to pull all the way to redline, let alone the increased volume after 4K rpm. It has made the car immensely more enjoyable to drive. So.. even if it's only Stout's #2 which changes, I still have zero regrets and would redo it all over again, especially considering how easily reversible everything is. but I'd be really surprised if #1 didn't change also.
But I challenge anyone with a regular spyder or gt4 to get into mine and not feel a massive difference from stock. 'UUGE difference from stock. Before it was strangled, now it's an animal. Smoothness, torque fullness, lugging from lower gears it just continues to pull all the way to redline, let alone the increased volume after 4K rpm. It has made the car immensely more enjoyable to drive. So.. even if it's only Stout's #2 which changes, I still have zero regrets and would redo it all over again, especially considering how easily reversible everything is. but I'd be really surprised if #1 didn't change also.
#105
Rennlist Member
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Of course, if one is chasing lap times, #1 matters—but if #2 improves driveability, usability, or driver confidence, it can have same or greater effect than gains in #1—especially if #1 gains come with sacrifices in #2.