GT4 RS Driving Impressions
#932
Last edited by lovetoturn; 05-08-2024 at 11:43 PM.
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7184RS (05-09-2024)
#933
- When just cruising at normal speeds not much over speed limits, the car isn't fun to drive, but it's reasonably comfortable because it's not too loud and the ride quality is good.
- When driving in a somewhat spirted manner, up to about 2x speeds limits, the car sounds more lively, but it has so much grip and stability that it's not particularly engaging to drive.
- When driving it pretty hard, closer to 7/10ths, the car is thrilling to drive and its potential starts to become apparent, but the speeds are so high that I think they're bordering on too fast for the road, even if one is being very careful.
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Manifold (05-08-2024)
#934
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Already feel that way (in bold) about my regular GT4 vs the older cars. I thought the car rode really well in general until I got on some rougher concrete roads we have just the other day. Putting the shocks in Sport made it laughable how much I was tossed around. Would love to try my buddy's 4RS on that same road. I told him it honestly felt like it rode better than my GT4, but that may just be down to him having PCCBs and Mags vs my iron rotor car. That was a very smooth road, though. Mostly chiming in to say that I have to imagine you have a high tolerance for ride or have some pretty smooth roads where you are if you don't mind running sport shocks on the street. I almost never turn those on unless it's on a very smooth canyon road. Really appreciating reading some of this feedback compared to other cars. I am quite interested in trying a McLaren and Emira someday soon.
Last edited by Manifold; 05-08-2024 at 11:51 PM.
#935
I'll stick to real life data myself. Arguing black is white when I have the data is daft who ever Grant is :-)
If he can show me a 4RS is faster going to 9k vs 8.5k on a time vs distance graph then that's upto him to back up his claim but atm he is wrong and I am right ;-)
While Porsche say max BHP is 8450rpm a lot of dyno's have it as circa 8100rpm in real life, and the graphs fall off a cliff after that. changing at 8500rpm is still way past peak bhp in real life and drops you back in a better sweet spot.
only reason to hold to 9k is if you can stop the car changing a gear for a fraction of a second at the end of a straight, some times is best to goto 8.8k vs fitting in another gear change. Then that is classed as a performance advantage, but it's the odd bend and not on all tracks, you just have that option to hold a gear if needed.
Look at a few dyno's posted (I looked at 3 just now) you loose cira 80bhp going to 9k and 80lbs/ft torque the drop off after 8100 rpm is massive.
I wonder if Grant realises on the 991.1 RS the cars max rpm is 8400 in one of the gears and still lower than 9k in the others. yes the engine blows up in 991.1's ;-p but 8400rpms in the famous RS models I bet is not published or talked about much.
If he can show me a 4RS is faster going to 9k vs 8.5k on a time vs distance graph then that's upto him to back up his claim but atm he is wrong and I am right ;-)
While Porsche say max BHP is 8450rpm a lot of dyno's have it as circa 8100rpm in real life, and the graphs fall off a cliff after that. changing at 8500rpm is still way past peak bhp in real life and drops you back in a better sweet spot.
only reason to hold to 9k is if you can stop the car changing a gear for a fraction of a second at the end of a straight, some times is best to goto 8.8k vs fitting in another gear change. Then that is classed as a performance advantage, but it's the odd bend and not on all tracks, you just have that option to hold a gear if needed.
Look at a few dyno's posted (I looked at 3 just now) you loose cira 80bhp going to 9k and 80lbs/ft torque the drop off after 8100 rpm is massive.
I wonder if Grant realises on the 991.1 RS the cars max rpm is 8400 in one of the gears and still lower than 9k in the others. yes the engine blows up in 991.1's ;-p but 8400rpms in the famous RS models I bet is not published or talked about much.
Last edited by mrd_spy; 05-09-2024 at 04:41 AM.
#936
BTW, it is clear from spy shots of the early mules of the 991.1 RS that Porsche had every intention of offering it with a 9k rpm redline, but lowered it in light of the valvetrain difficulties up there.
Also, you may remember that the power peak of the 991 GT3 and RS was lower at 8,250 rpm (rather than the current 8,500 rpm in the newest 3RS and S/T). I'm also interested that you are seeing independent testing results showing that GT4 RS has a power peak at only 8,100 rpm (with a steep decline thereafter). If this is so, why have you not chosen to shift at 8,100 rpm (given your expressed shifting rationale)?
Last edited by GrantG; 05-09-2024 at 11:44 AM.
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Ksdaoski (05-09-2024)
#937
As you say you have to shift just above above peak power, but the Cup engine GT models are not like normal cars.
Going to 9k is slower as peak power is 900rpm less than this so changing at 9k you loose 80 BHP. Are you coming round to the idea yet ?
As you own one of the the newer engines cars with the higher 6750 peak torque ? you must realise the cars are dead after 8.5k revs and you owning a manual you will never see 9k revs anyway. (I also had a manual 991.2 GT3 for 4 years and no way you changing at dead on 9k)
why you arguing black is white ? you don't even own a 4RS or a PDK GT3 for that matter.
As I own a PDK 4RS plus timing equipment and you don;t ! I'll try 8k revs just to get a 3rd time 100-200 it still might even beat the 9k changes. Something I can do and you cannot it seems ;-) , i see the times recorded in real life on a 992 GT3 100-200 is 7.46 seconds so a bit slower than my 7.2 manual changes in my 4rS and slower even than a PDK driven in auto also.
Cannot beat hard data.
Going to 9k is slower as peak power is 900rpm less than this so changing at 9k you loose 80 BHP. Are you coming round to the idea yet ?
As you own one of the the newer engines cars with the higher 6750 peak torque ? you must realise the cars are dead after 8.5k revs and you owning a manual you will never see 9k revs anyway. (I also had a manual 991.2 GT3 for 4 years and no way you changing at dead on 9k)
why you arguing black is white ? you don't even own a 4RS or a PDK GT3 for that matter.
As I own a PDK 4RS plus timing equipment and you don;t ! I'll try 8k revs just to get a 3rd time 100-200 it still might even beat the 9k changes. Something I can do and you cannot it seems ;-) , i see the times recorded in real life on a 992 GT3 100-200 is 7.46 seconds so a bit slower than my 7.2 manual changes in my 4rS and slower even than a PDK driven in auto also.
Cannot beat hard data.
#938
PDK Auto is slower end of , if you feel you need it to help you get round a track then thats all good, but people saying it's better and people saying you cannot fit 3 shift in is daft, learn how to drive and never buy a real manual car ! . Some times the Auto changes too much, some times it changes out the bend because it got it wrong, it don;t know there is a car in front if you catch one up so gets confuses why you are going a bit slower . I found Auto mode horrible. plus it's slower as it tries and get 9k revs from the car which is much slower than shifting earlier.
So you loose time every shift ! not gain time like people think !
So you loose time every shift ! not gain time like people think !
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#939
As you say you have to shift just above above peak power, but the Cup engine GT models are not like normal cars.
Going to 9k is slower as peak power is 900rpm less than this so changing at 9k you loose 80 BHP. Are you coming round to the idea yet ?
As you own one of the the newer engines cars with the higher 6750 peak torque ? you must realise the cars are dead after 8.5k revs and you owning a manual you will never see 9k revs anyway.
Going to 9k is slower as peak power is 900rpm less than this so changing at 9k you loose 80 BHP. Are you coming round to the idea yet ?
As you own one of the the newer engines cars with the higher 6750 peak torque ? you must realise the cars are dead after 8.5k revs and you owning a manual you will never see 9k revs anyway.
I guess the only disagreement remains the margin by which one should exceed the power peak rpm when shifting. You keep stressing the reduced power by shifting beyond the peak, but you have yet to address one of my key points that one must consider when choosing a shift point (where on the power curve you arrive after an upshift into the next higher gear, depends entirely on one's shift point in the prior gear and has enormous influence on overall performance). Perhaps your testing protocol does not allow for a long enough run, where you can make several shifts of this sort and run all the way through the tach more than once.
Although shifting beyond the power peak means you will have less than peak power before shifting, this is almost always a net advantage because you will improve acceleration after the shift (because you will be closer to the power peak in the next higher gear). You have to offset the small reduction in thrust in the original gear by the improvement in thrust in the higher gear if you land at a higher rpm, resulting from a shift closer to redline.
And, I will say that I see 9k rpm (or nearly 9k) quite often in my manual (confirmed by occasionally bumping the limiter on upshifts, unintentionally). I will concede that the manual has wider spaced ratios in its individual gear stack, compared to PDK (the revs fall more after an upshift due to having 6 ratios, rather than 7). So, it is even more beneficial to approach 9k rpm in the manual (no, my car doesn't feel dead as it approaches redline).
Last edited by GrantG; 05-09-2024 at 01:23 PM.
#940
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We don't know that mrd_spy is driving the car optimally, to the limit, in manual or auto mode, so his comparison of lap time doesn't really tell us much.
What I know is that it's a lot more fun for me to use the paddles, and I don't really care whether manual or auto is slightly faster, if there's any difference at all. Track days aren't racing.
What I know is that it's a lot more fun for me to use the paddles, and I don't really care whether manual or auto is slightly faster, if there's any difference at all. Track days aren't racing.
#941
Understood. I think for me if I am trying to learn a track with an instructor as a newbie I can see where Auto would help. That said, nothing feels better than controlling your own machine..
#942
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ChrisF (05-10-2024)
#943
Speaking of manuals, i tried the gear shifter to manually shift instead of the paddles. Having recently driving my mnaual car, the gear shifter felt very gimmicky. Thought id be ok with it or enjoy it because i loved playing arcade racing games as a kid with the same setup. Also of note i dont think it makes sense on track as paddles are faster for manual control.
#945
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Joined: May 2012
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From: Mid-Atlantic (on land, not in the middle of the ocean)
Speaking of manuals, i tried the gear shifter to manually shift instead of the paddles. Having recently driving my mnaual car, the gear shifter felt very gimmicky. Thought id be ok with it or enjoy it because i loved playing arcade racing games as a kid with the same setup. Also of note i dont think it makes sense on track as paddles are faster for manual control.