Reduced engine performance problem
01-14-2014, 02:06 PM
#47
Drifting
I'm going to have some fun and speculate here.
The 997.2 RS had a compression ratio of 12.2:1 which is very high for a street motor that runs on pump gas by default.
As if this wasn't crazy enough, the 997.3 had it raised again to 12.6:1. Andreas Preunninger himself said, “We played with ratios as high as 13.0:1. However, we encountered some detonation at this level, so we settled on 12.6:1"
With the 991's DFI and a few other tricks, the compression ratio is 12.9:1 (!). Anyone who has a bit of engine building knowledge knows this is insanely high for pump gas.
Throw in the 9,000 RPM redline and a splash of cheap fuel and we got a recipe for disaster.
ECU's these days are very advanced and I'm sure the knock sensor(s) in the 9A1 has very high resolution but that just means she's going to go to limp mode really easily which I suppose is better than throwing a connecting rod out of the block!
The 997.2 RS had a compression ratio of 12.2:1 which is very high for a street motor that runs on pump gas by default.
As if this wasn't crazy enough, the 997.3 had it raised again to 12.6:1. Andreas Preunninger himself said, “We played with ratios as high as 13.0:1. However, we encountered some detonation at this level, so we settled on 12.6:1"
With the 991's DFI and a few other tricks, the compression ratio is 12.9:1 (!). Anyone who has a bit of engine building knowledge knows this is insanely high for pump gas.
Throw in the 9,000 RPM redline and a splash of cheap fuel and we got a recipe for disaster.
ECU's these days are very advanced and I'm sure the knock sensor(s) in the 9A1 has very high resolution but that just means she's going to go to limp mode really easily which I suppose is better than throwing a connecting rod out of the block!
01-14-2014, 04:04 PM
#48
Nope.
01-14-2014, 11:24 PM
#49
est8esq,
I ran with you on the track a couple of times, the car looks beautiful.
Not sure about your experience level, but I think you were certainly beating the living daylights out of the car in the solo group.
I never saw you off the track and I was parked in a the far away corner of the paddock.
Thank you so much for sharing; Your report makes me so angry with Porsche...What a way to destroy your weekend.
We laugh and take bets, make jokes when we see the Lambo's Ferrari's, GTR's, BMW M etc show up because we know they don't last and we're very confident in our old GT3's.
BTW, we ran easy 10 hours of track time in the RSA and other guys in their high mileage GT3' with nothing more than adding gas tires, gas and pads..
Now you confirm our fears with the first 991 GT3 I see on track and iyt was not even hot!
Please keep us posted.
Just another fast car that's not track proven and not track worthy until proven otherwise...
I ran with you on the track a couple of times, the car looks beautiful.
Not sure about your experience level, but I think you were certainly beating the living daylights out of the car in the solo group.
I never saw you off the track and I was parked in a the far away corner of the paddock.
Thank you so much for sharing; Your report makes me so angry with Porsche...What a way to destroy your weekend.
We laugh and take bets, make jokes when we see the Lambo's Ferrari's, GTR's, BMW M etc show up because we know they don't last and we're very confident in our old GT3's.
BTW, we ran easy 10 hours of track time in the RSA and other guys in their high mileage GT3' with nothing more than adding gas tires, gas and pads..
Now you confirm our fears with the first 991 GT3 I see on track and iyt was not even hot!
Please keep us posted.
Just another fast car that's not track proven and not track worthy until proven otherwise...
Haha, I have to be honest. I brought a '13 GTR to Sebring Winterfest last year and got tired of the GT3's in my rear view mirror all the time. So, I bought a '14 GTR and had it built by Switzer Performance into a 1200hp track car thinking it was the answer, but the heat it generated was nuts and was towed off track, broken down on so many early trials that this event w/ my GT3 doesn't bother me that much. I at least got a full day running.
I spoke w/ Suncoast in Sarasota and they told me they had to get a hold of Porsche direct and tried sharing what they sent (had something to do w/ technical bulletins using acronyms I didn't get?). So, we're in a hurry up and wait period?
Will have to keep you all posted on status?
I decided while down at PBOC Winterfest that I'm going to attend the 48Hours at Sebring at the end of this month (next week) since my car is still down there already and hope to be able to get this back on the road by then.
Cleveland isn't a good place to track cars at this time of year.
Last edited by est8esq; 07-07-2014 at 10:56 PM.
01-15-2014, 12:06 AM
#51
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I'm flying home from Sebring after Winterfest and had the same problem.
The first time it happened, it ended up being a faulty cam sensor. They replaced it and after driving back from Sarasota, it ran fine for one full day. Then, it went into limp mode again showing the same, reduced performance warning. So, we too it off the track and left it overnight. When I went to get it over to a local dealership to await the flatbed, I had similar issues w/ the lift when when it was still working. Then, only a few minutes into my drive, the engine temp went out. Then, the engine fans went crazy thinking the car was overheating?
I'm about to catch flight back home, so waiting to hear what status of my car is??
On a side note, this car on track is absolutely unbelievable… when it' running.
The first time it happened, it ended up being a faulty cam sensor. They replaced it and after driving back from Sarasota, it ran fine for one full day. Then, it went into limp mode again showing the same, reduced performance warning. So, we too it off the track and left it overnight. When I went to get it over to a local dealership to await the flatbed, I had similar issues w/ the lift when when it was still working. Then, only a few minutes into my drive, the engine temp went out. Then, the engine fans went crazy thinking the car was overheating?
I'm about to catch flight back home, so waiting to hear what status of my car is??
On a side note, this car on track is absolutely unbelievable… when it' running.
Sounds like minor new car stuff. How many miles on the car?
The car is quick and looks like a lot of fun.
I wouldnt worry to much about it.
Your GTR is insane by the way!
01-15-2014, 01:51 AM
#52
Rennlist Member
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
01-15-2014, 07:00 AM
#53
Whilst I agree that there will always be a few gremlins on a new car, it certainly hasnt affected everyone.
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
01-15-2014, 08:38 AM
#54
Whilst I agree that there will always be a few gremlins on a new car, it certainly hasnt affected everyone.
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
01-15-2014, 12:33 PM
#55
Rennlist Member
Sam, thank you for testing this car hard and finding out the little bugs. I have little doubt Porsche will fix all of them and the 991 GT3 will turn out to be a great track car with no problems over the course of a hard track weekend. Any brand new car platform, especially one as advanced as the new GT3, is going to have minor teething issues at the beginning.
As 911Dev said, even developed platforms still have issues several model years into production. Every car has it's quirks, save for maybe a boring Lexus.
As 911Dev said, even developed platforms still have issues several model years into production. Every car has it's quirks, save for maybe a boring Lexus.
01-15-2014, 06:46 PM
#56
Rennlist Member
That would make me feel just like I felt with my Diesel Dually Chevy going into limp mode as soon as I put a trailer on it.. Great truck just don't use it as advertised, at least the Chevy was cheap and I got what I paid for..
Was my first and last Chevy BTW.
Whilst I agree that there will always be a few gremlins on a new car, it certainly hasnt affected everyone.
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
Estimates suggest around 6-700 991 GT3 have now been produced and delivered to customers, and I know myself or around 14-15 folk who have had their car out on the track. No to mention myself and at least half a dozen other who have now put 2500+ miles on the car. These cam sensor issues may only have occurred to a small number of those cars as I have not yet heard about such issues from the UK or Europe.
Remember 997.2 GT3/RS and 4.0RS owners have had their fair share of issues too with CLs, Manifold intakes, front lifters and at least half a dozen other minor and not so minor bulletins.
Assuming its a faulty cam sensor and a bad batch I cant see thus ruining anyone's fun. If its a global component problem then ok its a hassle for everyone but not a show stopper. lets wait and see before jumping to conclusions. Like I say myself and many other hard driven cars have not yet seen this issue....
Just my 2c worth.
Little things braking down or going in limp mode on the way to Woolworth is fine to me, its warranty. Not finishing a track weekend and see me throw a hissy fit.
Everything that was an issue with the 997 was basically a part that differed from the CUP car; We were the lab rats, but at least for those parts only..
I did not finish only one weekend in 150+ track days due to the clutch failing after 14K miles.. Yes there were issues big and small and I am sure some surfaced on the first track day but at least it felt like me less like black magic issues like computers going into limp mode. Seems the older I get the more old fashioned I get.
Just 0.02c from an idiot who made the same biggest mistake of his year as that other idiot Chris Harris..
01-15-2014, 07:20 PM
#58
Rennlist Member
I don't know, after all the test miles at the Ring and it being a GT3 going in limp mode on track? That's GTR and Lambo stuff right there.
That would make me feel just like I felt with my Diesel Dually Chevy going into limp mode as soon as I put a trailer on it.. Great truck just don't use it as advertised, at least the Chevy was cheap and I got what I paid for..
Was my first and last Chevy BTW.
Its minor until you travel 2000 miles and take a week of for a track event.
Little things braking down or going in limp mode on the way to Woolworth is fine to me, its warranty. Not finishing a track weekend and see me throw a hissy fit.
Everything that was an issue with the 997 was basically a part that differed from the CUP car; We were the lab rats, but at least for those parts only..
I did not finish only one weekend in 150+ track days due to the clutch failing after 14K miles.. Yes there were issues big and small and I am sure some surfaced on the first track day but at least it felt like me less like black magic issues like computers going into limp mode. Seems the older I get the more old fashioned I get.
Just 0.02c from an idiot who made the same biggest mistake of his year as that other idiot Chris Harris..
That would make me feel just like I felt with my Diesel Dually Chevy going into limp mode as soon as I put a trailer on it.. Great truck just don't use it as advertised, at least the Chevy was cheap and I got what I paid for..
Was my first and last Chevy BTW.
Its minor until you travel 2000 miles and take a week of for a track event.
Little things braking down or going in limp mode on the way to Woolworth is fine to me, its warranty. Not finishing a track weekend and see me throw a hissy fit.
Everything that was an issue with the 997 was basically a part that differed from the CUP car; We were the lab rats, but at least for those parts only..
I did not finish only one weekend in 150+ track days due to the clutch failing after 14K miles.. Yes there were issues big and small and I am sure some surfaced on the first track day but at least it felt like me less like black magic issues like computers going into limp mode. Seems the older I get the more old fashioned I get.
Just 0.02c from an idiot who made the same biggest mistake of his year as that other idiot Chris Harris..
The 997.2 Gen GT3 had its fair share of issues, especially when you consider this was a much tested platform. The 996.1 GT3 by comparison had relatively few issues given it was a brand new platform. The 991 GT3 is possibly a bigger platform shift than even the 996 GT3 was and also a shift in philosophy (integration of effectively all current model 991 electric performance systems such as PTV, dynamic mounts, electronic diff, ESC, TC, PSAM and with a few new ones such as RWS). Its a bloody big jump. If a few thermostats and cam sensors fail along the way I dont see that as endemic or surprising. If however this is the beginning of many small or small and large gremlins then I do see that as an issue.
However there will probably be 1000+ 991 GT3 circulating the world within the next 90 days in all climates being driven hard, on track and road (or cosseted under covers and waxed for cafe cruisers) and this real world test has already well got under way now. Within the next 90-180 days I think will be important for this car IMHO....
All this said, you could do worse than to put one of these in the garage next to the 964 race car mate. I think you already have an RS on order. They are so different like night and day as to be a hoot each for their own specific characters...
01-15-2014, 07:40 PM
#59
Rennlist Member
I don't know, after all the test miles at the Ring and it being a GT3 going in limp mode on track? That's GTR and Lambo stuff right there.
That would make me feel just like I felt with my Diesel Dually Chevy going into limp mode as soon as I put a trailer on it.. Great truck just don't use it as advertised, at least the Chevy was cheap and I got what I paid for..
Was my first and last Chevy BTW.
Its minor until you travel 2000 miles and take a week of for a track event.
Little things braking down or going in limp mode on the way to Woolworth is fine to me, its warranty. Not finishing a track weekend and see me throw a hissy fit.
Everything that was an issue with the 997 was basically a part that differed from the CUP car; We were the lab rats, but at least for those parts only..
I did not finish only one weekend in 150+ track days due to the clutch failing after 14K miles.. Yes there were issues big and small and I am sure some surfaced on the first track day but at least it felt like me less like black magic issues like computers going into limp mode. Seems the older I get the more old fashioned I get.
Just 0.02c from an idiot who made the same biggest mistake of his year as that other idiot Chris Harris..
That would make me feel just like I felt with my Diesel Dually Chevy going into limp mode as soon as I put a trailer on it.. Great truck just don't use it as advertised, at least the Chevy was cheap and I got what I paid for..
Was my first and last Chevy BTW.
Its minor until you travel 2000 miles and take a week of for a track event.
Little things braking down or going in limp mode on the way to Woolworth is fine to me, its warranty. Not finishing a track weekend and see me throw a hissy fit.
Everything that was an issue with the 997 was basically a part that differed from the CUP car; We were the lab rats, but at least for those parts only..
I did not finish only one weekend in 150+ track days due to the clutch failing after 14K miles.. Yes there were issues big and small and I am sure some surfaced on the first track day but at least it felt like me less like black magic issues like computers going into limp mode. Seems the older I get the more old fashioned I get.
Just 0.02c from an idiot who made the same biggest mistake of his year as that other idiot Chris Harris..
01-15-2014, 08:33 PM
#60
Three Wheelin'
