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JSG1901

DISCUSSION CLOSED: Add a factor for sequential gearboxes

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JSG1901
As far as the stock PDks, DSG, or whatever they may be called, on a stock car they have a built in weight penalty due to the weight of the system over a manual transmission, yet they do run quicker lap times in the hands of journalists, or even professional test drivers for Porsche.

Again for clarification, several posts here have mentioned the additional weight of the sequential boxes. Just so we're all singing from the same hymnal, let's be clear that regardless of how the cars come from the factory, there is no such thing as a "built-in weight penalty" in GTS.

 

The weight penalty people are referring to here is that these cars, from the factory, weigh more with the fancy gearboxes than with the more conventional 6-speed (or however-many speed) manual gearboxes.

 

That's all well and good but has nothing to do with their GTS minimum weights. If the gearbox weighs an extra 50 lbs, that simply means you need 50 lbs less ballast, or a little less fuel, or some fiberglass doors to make up for it. Unless we decide to add an additional factor for some or all of these gearboxes, there is zero weight penalty for having one.

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thehounder

While I won't say vouch for the science here is a demonstration of lap time between three manual and auto-manual cars run by an Asian car show...I can't understand the dialogue but it does show a comparison of same cars equipped with two different transmissions competing with pro-drivers.

 

 

For those of you who aren't interested in watching the entire video here are the lap times. Showing Fastest lap for each car.

 

EVO GSR Best lap 1'05.69

Ferrari 360 6MT 1'05.41

Ferrari 360 F1 1'06.59

M3 6MT 1'08.29

EVO GT-A 1'08.12

M3 SMG II 1'09.05

 

For those of you who have a different set of outcomes please post your numbers. With all due respect, I think that aftermarket boxes should carry some sort of a penalty, but painting with too broad of a brush "as a precaution for the future" or without hard data, like wins or lap times is not science, but speculation. If there is other data that shows different results I'm open, (as I'm sure we all are) to seeing it, as I hope that a reasonable decision can be made that accurately reflects advantage where it exists, not simply where we think it might.

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Luke P.

Max - is your car SMG?

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thehounder
Max - is your car SMG?

 

Yes it is... thought I called that out.

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autodoctor911
As far as the stock PDks, DSG, or whatever they may be called, on a stock car they have a built in weight penalty due to the weight of the system over a manual transmission, yet they do run quicker lap times in the hands of journalists, or even professional test drivers for Porsche.

Again for clarification, several posts here have mentioned the additional weight of the sequential boxes. Just so we're all singing from the same hymnal, let's be clear that regardless of how the cars come from the factory, there is no such thing as a "built-in weight penalty" in GTS.

 

The weight penalty people are referring to here is that these cars, from the factory, weigh more with the fancy gearboxes than with the more conventional 6-speed (or however-many speed) manual gearboxes.

 

That's all well and good but has nothing to do with their GTS minimum weights. If the gearbox weighs an extra 50 lbs, that simply means you need 50 lbs less ballast, or a little less fuel, or some fiberglass doors to make up for it. Unless we decide to add an additional factor for some or all of these gearboxes, there is zero weight penalty for having one.

 

I'm sorry, I thought the fact that there was no weight penalty in GTS right now was well known already, and the reason for this discussion, or I would have pointed it out. I should have said that the advantages in a stock PDK car overcome the slight weight disadvantage they have stock, which goes away when they are regulated to the same weight to HP. On a Boxster or Cayman, there might be a slight weight distribution disadvantage even when they have the same minimum weight though, since the weight is hanging out over the rear axle, where as ballast would probably be put in the center of the car, but those cars already have superb weight distribution compared to most other cars.

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autodoctor911

How about 8 seconds a lap at Nurburg ring?

http://www.egmcartech.com/2008/06/27/video-2009-porsche-911-pdk-test-drive/

 

Without Porsche’s new double-clutch 7-speed automatic PDK transmission, the Carrera Coupe gets a combined fuel-economy 21.3mpg – with PDK the Carrera gets 24mpg. Great - it increases fuel-economy; but what about performance?

According to Porsche the new PDK dual-clutch 7-speed automatic is 60 percent faster than the Tiptronic S automatic. In a recent test at the Nurburgring, the 2009 911 Carrera S with PDK returned a lap of time of 7:50. The 2009 Porsche 911 Carrera S with manual transmission was 8 seconds slower at 7:58.

So PDK is the definitely the way to go even if you’re a true stick fan. Check out this review by our friends at CAR.

Click through for the video.

 

also reported here:

http://www.themotorreport.com.au/5267/2009-porsche-911s-tackles-the-nurburgring

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vwmann1
Scott:

If you would, I would respectfully request that the verbiage of the rule change be changed. As it stands right now the BMW SMG is singled out as the great offender. As I posted in my original rule change request, I would like to see all of the sequential/double clutch/auto-shifted manual gearboxes added to this rule.

 

If we have one rule it will make the enforcement easier and leave less gray area to be debated.

 

Thank you.

How should it read after the edit?

 

Can you put the link back up so I can submit a revised proposal.

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maxxfish

I race a DTC-transmission in an M3 in GTS-4, and I'm sorry to say that there is so much ignorance here from those who aren't familiar with these transmissions:

 

1. Price creep:

These transmissions DO NOT create price creep in the series. In fact, DCT cars are cheaper to buy on the used market. I paid $2000 less than a similarly equipped 6-speed.

You cannot upgrade the clutch or flywheel. A JB Racing setup for a 6-speed is $2350.

My car is 50 pounds heavier than a 6-speed. I know this is built in weight, I understand the concept. BUT... these cars are heavy, and even fully gutted and tuned, I'm still nowhere near the class power-to-weight threshold. So to get to that magic threshold, I'm looking at carbon bodywork, which means big $$$.

 

2. Performance:

Yes, I can put my foot to the floor and run up the gears. But even though the downshifts are quick, I have to wait in between each shift.

I can't skip gears. You know when those crappy CMC cars screw you up so bad that you have to panic brake, then bump down from 4th gear to 2nd just to get going again? I have to go 4-3-2. Trust me it happens a lot, and I lose time.

I have a clutch/flywheel that is 25 pounds heavier than a performance setup for a 6-speed. 25 pounds less rotating mass in the driveline makes for lots of time gains AFTER the shift. What's the penalty for that?

 

3. Complexity/durability:

So far my transmission has be completely reliable for 25-minute sprint races, and 40 minute races on cold days. I haven't run a 40-minute race in the summer yet. But downshifting DOES slow down towards the end of a 25-minute race. To alleviate that, I run my trans in #4 mode. That's 4 out of 6 in terms of aggressiveness of shifts. It's no 997 Cup in that mode.

 

4. So, why did I get a DCT car?

I thought it would be fun, and it is. It's like playing a video game.

I like to be the black sheep.

I like that my friends tease me for driving a car with "Pu$$y Paddles."

 

Fini. Max

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Michael G.

I race a DTC-transmission in an M3 in GTS-4, and I'm sorry to say that there is so much ignorance here from those who aren't familiar with these transmissions:

 

1. Price creep:

These transmissions DO NOT create price creep in the series. In fact, DCT cars are cheaper to buy on the used market. I paid $2000 less than a similarly equipped 6-speed.

You cannot upgrade the clutch or flywheel. A JB Racing setup for a 6-speed is $2350.

My car is 50 pounds heavier than a 6-speed. I know this is built in weight, I understand the concept. BUT... these cars are heavy, and even fully gutted and tuned, I'm still nowhere near the class power-to-weight threshold. So to get to that magic threshold, I'm looking at carbon bodywork, which means big $$$.

 

2. Performance:

Yes, I can put my foot to the floor and run up the gears. But even though the downshifts are quick, I have to wait in between each shift.

I can't skip gears. You know when those crappy CMC cars screw you up so bad that you have to panic brake, then bump down from 4th gear to 2nd just to get going again? I have to go 4-3-2. Trust me it happens a lot, and I lose time.

I have a clutch/flywheel that is 25 pounds heavier than a performance setup for a 6-speed. 25 pounds less rotating mass in the driveline makes for lots of time gains AFTER the shift. What's the penalty for that?

 

3. Complexity/durability:

So far my transmission has be completely reliable for 25-minute sprint races, and 40 minute races on cold days. I haven't run a 40-minute race in the summer yet. But downshifting DOES slow down towards the end of a 25-minute race. To alleviate that, I run my trans in #4 mode. That's 4 out of 6 in terms of aggressiveness of shifts. It's no 997 Cup in that mode.

 

4. So, why did I get a DCT car?

I thought it would be fun, and it is. It's like playing a video game.

I like to be the black sheep.

I like that my friends tease me for driving a car with "Pu$$y Paddles."

 

Fini. Max

"

 

Max, Thank you.

That is exactly what I was trying to say.

 

Michael G.

NE GTS Dir.

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vwmann1

Time reduction:

ABCC: 5 upshifts 1.5 sec.

Gingerman: 6 upshifts 1.8 sec

Mid Ohio: 7 upshifts 2.1 sec

Road America: 11 upshifts 3.3 seconds

 

Difference in track records between 3 and 4

ABCC: 1.8 sec

Gingerman: 2.9 sec

Mid Ohio: 1.8 sec

Road America: 4.9 sec

Just as a clarification on the math, unless I misunderstand what you're saying, the times shown here are not differences in lap time but, rather, the additional amount of time each lap that a sequential-gearbox car would be on the gas. Right?

 

The number I quoted are reductions in lap time. I arrived at these assumptions the following way: In an effort to try and take out any skew and reduce variables, I took the fastest possible time for an h-pattern shift (.35/sec) and the slowest possible time for a sequential shift (.05/sec) from the numbers posted by another member. That number turned out to be .3 of a second. I then reviewed data from my customers and arrived at an average number of up shifts per lap. I did not include down shifts because there is no real way to quantify the time savings. Then multiply the number of shifts by .3 and arrived at a total time saved per lap. It is reasonable to assume if you are not accelerating you are slowing by the difference thus the time savings. I understand that these number are not exact science, by I made the two number as slow or as fast as even the most talented drive could achieve to try and not have them look too good or bad. Even with that skew I was shocked at what I found.

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gofastzach

I am close friends with the pro driver coach to Geoff Issringhausen of the ITC racing cayman series. They recently built a PDK Cayman. They were able to get it down to the same competition weight as the standard 6-speed. ITC placed a 90lb weight penalty on any PDK equipped chassis and at the last weekend they were at abcc Geoff went 2 seconds a lap faster. Even with the weight penalty he was substantially faster. I would also consider Geoff to be of equivalent driving skill to the majority of GTS drivers.

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vwmann1
Max - is your car SMG?

 

Yes it is... thought I called that out.

 

 

So, you have data that could help. Can I ask why you have not posted it here or at least sent it to Scott for analysis?

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thehounder
Max - is your car SMG?

 

Yes it is... thought I called that out.

 

 

So, you have data that could help. Can I ask why you have not posted it here or at least sent it to Scott for analysis?

 

What data is that? My car is not done (not caged nor at weight)and hasn't run in two years due to some medical issues that I have had. Please don't attempt to call me out for with holding info, I have been respectful and it would be nice to have the same courtesy. I shared the data that I found, which I believe is relevant.

 

Doug - Please share your data, I would imagine as you suggested the rule, you have stacks of data to back it up.

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vwmann1

 

 

So, you have data that could help. Can I ask why you have not posted it here or at least sent it to Scott for analysis?

 

What data is that? My car is not done (not caged nor at weight)and hasn't run in two years due to some medical issues that I have had. Please don't attempt to call me out for with holding info, I have been respectful and it would be nice to have the same courtesy. I shared the data that I found, which I believe is relevant.

 

Doug - Please share your data, I would imagine as you suggested the rule, you have stacks of data to back it up.

 

I have posted data.

So let me get this straight, once again we have someone who doesn't race in the series trying to influence the rules. interesting. This is the last time I respond to your questions.

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thehounder

 

I have posted data.

So let me get this straight, once again we have someone who doesn't race in the series trying to influence the rules. interesting. This is the last time I respond to your questions.

 

You have posted opinion, and voodoo analysis. Nothing more.

 

No this is someone who is building for the series. With that said, are you a GTS driver or a shop owner, or the father of a racer? I'm confused. How is it you get a say and I don't?

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JSG1901
Can you put the link back up so I can submit a revised proposal.

 

Doug,

 

Just e-mail it to me and I'll post it for you.

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gofastzach

 

I have posted data.

So let me get this straight, once again we have someone who doesn't race in the series trying to influence the rules. interesting. This is the last time I respond to your questions.

 

You have posted opinion, and voodoo analysis. Nothing more.

 

No this is someone who is building for the series. With that said, are you a GTS driver or a shop owner, or the father of a racer? I'm confused. How is it you get a say and I don't?

 

Vwmann1 aka Douglas Hillmann is my father, crew chief, engineer,and most importantly my financial backing. he has also built a total of 6 cars that have raced/are racing in GTS along with one of the first ever. We have built and designed our car together and I do the easy part of driving It. We share the same opinions on this matter and have developed our responses together. Therefor I give him full cart blanch to post on my behalf. Hope that clears up his role within our team and gts as a series.

 

Now back on topic please

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autodoctor911
I race a DTC-transmission in an M3 in GTS-4, and I'm sorry to say that there is so much ignorance here from those who aren't familiar with these transmissions:

 

1. Price creep:

These transmissions DO NOT create price creep in the series. In fact, DCT cars are cheaper to buy on the used market. I paid $2000 less than a similarly equipped 6-speed.

You cannot upgrade the clutch or flywheel. A JB Racing setup for a 6-speed is $2350.

My car is 50 pounds heavier than a 6-speed. I know this is built in weight, I understand the concept. BUT... these cars are heavy, and even fully gutted and tuned, I'm still nowhere near the class power-to-weight threshold. So to get to that magic threshold, I'm looking at carbon bodywork, which means big $$$.

 

2. Performance:

Yes, I can put my foot to the floor and run up the gears. But even though the downshifts are quick, I have to wait in between each shift.

I can't skip gears. You know when those crappy CMC cars screw you up so bad that you have to panic brake, then bump down from 4th gear to 2nd just to get going again? I have to go 4-3-2. Trust me it happens a lot, and I lose time.

I have a clutch/flywheel that is 25 pounds heavier than a performance setup for a 6-speed. 25 pounds less rotating mass in the driveline makes for lots of time gains AFTER the shift. What's the penalty for that?

 

3. Complexity/durability:

So far my transmission has be completely reliable for 25-minute sprint races, and 40 minute races on cold days. I haven't run a 40-minute race in the summer yet. But downshifting DOES slow down towards the end of a 25-minute race. To alleviate that, I run my trans in #4 mode. That's 4 out of 6 in terms of aggressiveness of shifts. It's no 997 Cup in that mode.

 

4. So, why did I get a DCT car?

I thought it would be fun, and it is. It's like playing a video game.

I like to be the black sheep.

I like that my friends tease me for driving a car with "Pu$$y Paddles."

 

Fini. Max

 

 

Well, if you are having trouble making the power to weight for GTS-4, then it sounds like a good GTS-3 car.

 

Are you saying that the M-DCT would not in fact run 2 seconds or more per lap lower lap time at a 2 plus mile road coarse for the duration of a 15-45minute race compared to a 6 speed manual with a clutch, flywheel upgrade?

 

You say that your M-dct car was $2000 cheaper than a 6 speed car. Why are they going for cheaper? A Popular $2000+ option on a new car has become a $2000 deduction from the value on a used car?

 

From what I have seen, even the old, much maligned E46 SMGs are still getting a premium. KBB shows no difference for BMWs with or without the SMG or M-dct. They show about a $1200 premium on a Porsche with PDK, and about a $700 premium for a VW GTI. I don't see why the market would penalize a popular and much liked premium transmission option that is easier to drive, faster and gets better fuel mileage on a late model BMW that most people use to commute to work most of the time. Plus, you are comparing to another car that is also quite expensive for a base vehicle to turn into a race car. By the time you build that car, I'm pretty sure you'll have as much in it as if someone bought a used 997-1 cup car. Most of the GTS cars start out as much cheaper street cars than a E9x, 0r FX0 BMW. There is no way you could consider that an affordable build in GTS3, or even 4. I would agree though that the price difference between two late model BMWs, one with and one without M-dct is not a major cost difference initially, but like you said, it will cost more to make weight, and modify the cooling system and programming for best results, and it will definitely not be an affordable option for anyone already running an older car.

 

Oh, and under your reasons for getting one, it being faster was not a consideration?

Of course anyone that has one is going to say that it's not an advantage, and should not be penalized, and anyone who doesn't will say it is and should. The only way to resolve this would be to compare lap times from an independent source. The Claims from Manufacturers may be somewhat suspiscious due to the fact that they may be promoting a technology that they have developed, as well as trying to sell a profitable option, or a car that is now only available with this type of transmission, but they can be one source. Any independent testing with Professional test drivers, or seasoned amateur road racers would be best.

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autodoctor911

Just as a clarification on the math, unless I misunderstand what you're saying, the times shown here are not differences in lap time but, rather, the additional amount of time each lap that a sequential-gearbox car would be on the gas. Right?

The number I quoted are reductions in lap time. I arrived at these assumptions the following way: In an effort to try and take out any skew and reduce variables, I took the fastest possible time for an h-pattern shift (.35/sec) and the slowest possible time for a sequential shift (.05/sec) from the numbers posted by another member. That number turned out to be .3 of a second. I then reviewed data from my customers and arrived at an average number of up shifts per lap. I did not include down shifts because there is no real way to quantify the time savings. Then multiply the number of shifts by .3 and arrived at a total time saved per lap. It is reasonable to assume if you are not accelerating you are slowing by the difference thus the time savings. I understand that these number are not exact science, by I made the two number as slow or as fast as even the most talented drive could achieve to try and not have them look too good or bad. Even with that skew I was shocked at what I found.

 

Don't get me wrong, I'm with you here on these being faster and should be penalized, but I have a question about your math.

 

are you figuring the difference in shift times as a difference in lap times?

 

Neither car is sitting still while shifting. The shift time isn't even as important as the throttle off time, and the amount of time gained or lost during a shift is not even equal to that throttle off time, but is a more complex calculation based on how fast the car is going, how fast it is accelerating on throttle, and how much it decelerates off throttle, as well as the throttle off time.

 

The throttle off time is typically longer than the shift time on any manual release and application of throttle with a shift, and about equal to it on a "flatshifter" type setup on a full sequential. The dual clutch transmissions don't even have to go off throttle. Of course any old drag racer will tell you that you can do a speed shift on a synchro tranny without lifting, but I don't think it will last very long that way.

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Michael G.

Autodoctor911,

 

I am sure Max can reply, but I wanted to add, that despite what KBB listing for the values of the used cars - in the BMW circles the E46 SMG equipped M3s has less value than 6 - speeds, and the same is true for E9X. I don't know, what Max's experience, but mine is exactly as you indicated - the SMG equipped E46M3 will not be any faster than the 6 - speed, exactly because of the limitations it comes with - overheating, heavy flywheel, stock ECU, etc. If it would be any different, we would see many of those racing - it was available since 2002. Virtually none or very few are being raced and none winning. DCTs are around since 2008 in the E9X M3s. And we are still waiting to see them to show up. Again, even factory supported BMW team didn't use factory DCT for their ALMS car once switched form manual. I think the 3 disc Tilton triple plate clutch / 6 - speed sequential with the oil cooler used. Regarding the cost - even with the all upgrades it will be far off the 997 P Cup Car.

On the times comparison - you can look at the latest results from the MA Region run at VIR OctoberFast. - Max was running his DCT E9X M3 in GTS 4 and Josh Smith run his 6-speed E9X M3 in two trims - GTS 3 and 4 depending on the ECU map. I can only assume, he has the clutch / flywheel upgrade (we can ask him to clarify), I know he has ECU upgrade, otherwise, I would guess both cars are pretty similar. Both drivers are very experienced and know VIR as the home track. Race 1 - Josh (GTS3) - 2:03.8, Max (GTS4) - 2:06.0,

Race 2 - JS (GTS3) - 2:11.8, MF (GTS4) - 2:12.5.

By the way, in the stock E46 SMG M3 you need to get off the throttle to shift.

 

Michael G.

NE GTS Dir.

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Eric W.

 

The number I quoted are reductions in lap time. I arrived at these assumptions the following way: In an effort to try and take out any skew and reduce variables, I took the fastest possible time for an h-pattern shift (.35/sec) and the slowest possible time for a sequential shift (.05/sec) from the numbers posted by another member. That number turned out to be .3 of a second. I then reviewed data from my customers and arrived at an average number of up shifts per lap. I did not include down shifts because there is no real way to quantify the time savings. Then multiply the number of shifts by .3 and arrived at a total time saved per lap. It is reasonable to assume if you are not accelerating you are slowing by the difference thus the time savings. I understand that these number are not exact science, by I made the two number as slow or as fast as even the most talented drive could achieve to try and not have them look too good or bad. Even with that skew I was shocked at what I found.

 

Wait a sec here, shift reductions times are not equal to laptime saved. Saving 0.3 secs in a shift doesnt drop your laptime by 0.3 secs.

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mikew968

Intersting discussion!!

 

What I read here is almost entirely speculation. Lap time savings being calculated theoretically by the shift time savings, journalists being faster in a PDK, or the the "Ring" time improvement with a PDK. What is lacking is actual race times in actual races at the tracks we race by the people we race with. In other words actual results. Now for full disclosure I am building a PDK and I "hope" it will be faster but there really isn't any proof that will be the case. As I already stated in World Challenge there is no PDK penalty and yet the best Cayman driver out there chose a 6 speed. He did that because there are issues like overheating, gremlins messing with the trans, ghost shifts or refusing to shift etc etc. I'm not sure I made the right choice to build a PDK but I am committed at this point. When you talk to BodyMotion or other Cayman ITC builders they do not all agree PDK is a big advantage and the one driver as quoted being 2 seconds faster is pretty slow to start with! Were the PDK CAymans faster than the GTS-4 cars at Mid Ohio this summer when they ran with Great Lakes? Well go ahead and look up the results for yourself!! I believe when there is an actual proven advantage then we can should talk about whether to penalize these transmissions or not. If we took this proactive appoach there would be no aero. Is that what we want? The open rule set in GTS is pretty awesome and has worked pretty well so far!

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Brad Waite

Having read Mike Ward's and other posts, I do think he makes some great points and I now weigh in with a "no vote" at this time for a gearbox penalty. I do have a strong vested interest in the topic, as I race a 6 speed GTS4 car and most likely will be competing against Mike next year in his PDK GTS4 car, depending upon how his numbers work out.

 

My viewpoint on many topics, is to avoid trying to correct a problem that doesn't exist. I don't think we have a competition problem stemming from the gearbox question now and any ruleset change would be anticipatory, and quite possibly either misguided or imprecise in the penalty calculation.

 

On the BMW side, the SMG tranny is inferior and the DCT although much better, is not being widely raced. On the Porsche side, the PDK is very good and comparable to the DCT, but also not widely raced. The 997 Cup cars with sequential boxes are all grouped together in GTS5, where few cars exist anyway, and I haven't heard any fairness grumblings there.

 

I say let's table the change, learn more and resolve the problem, if and when, one exists.

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autodoctor911
Autodoctor911,

 

I am sure Max can reply, but I wanted to add, that despite what KBB listing for the values of the used cars - in the BMW circles the E46 SMG equipped M3s has less value than 6 - speeds, and the same is true for E9X. I don't know, what Max's experience, but mine is exactly as you indicated - the SMG equipped E46M3 will not be any faster than the 6 - speed, exactly because of the limitations it comes with - overheating, heavy flywheel, stock ECU, etc. If it would be any different, we would see many of those racing - it was available since 2002. Virtually none or very few are being raced and none winning. DCTs are around since 2008 in the E9X M3s. And we are still waiting to see them to show up. Again, even factory supported BMW team didn't use factory DCT for their ALMS car once switched form manual. I think the 3 disc Tilton triple plate clutch / 6 - speed sequential with the oil cooler used. Regarding the cost - even with the all upgrades it will be far off the 997 P Cup Car.

On the times comparison - you can look at the latest results from the MA Region run at VIR OctoberFast. - Max was running his DCT E9X M3 in GTS 4 and Josh Smith run his 6-speed E9X M3 in two trims - GTS 3 and 4 depending on the ECU map. I can only assume, he has the clutch / flywheel upgrade (we can ask him to clarify), I know he has ECU upgrade, otherwise, I would guess both cars are pretty similar. Both drivers are very experienced and know VIR as the home track. Race 1 - Josh (GTS3) - 2:03.8, Max (GTS4) - 2:06.0,

Race 2 - JS (GTS3) - 2:11.8, MF (GTS4) - 2:12.5.

By the way, in the stock E46 SMG M3 you need to get off the throttle to shift.

 

Michael G.

NE GTS Dir.

 

On the E46 SMG the DME backs off the throttle, since it is a single clutch. The only reason the driver would need to back off the throttle is to get it to short shift(early upshift). Correct me if I'm wrong, it has been a while, but I don't remember having to lift to shift.

 

I have driven a few of the E46 SMGs and I would agree that that would not make a very good racing transmission, regardless of whether there are penalties or no penalties. I don't think it would be wise to run one even now, and I don't see much, if any advantage in lap times for that particular car/transmission. It is single clutch, and fairly slow shifting. I know I can shift a regular E46 6Mt faster. The only advantage it may have is reduced work for the driver, allowing him/her to concentrate more on other stuff that may pick up time, but that's not the kind of thing I would like to see penalized.

 

It's impossible to deny that the dual clutch transmissions are faster though. It is evident in straightline acceleration figures. And I don't think reliability is a big deal or they would have major warranty issues. They may loose a little performance if they are pushed to the limits on a hot day for several hours or more, but that could be remedied with better oil cooling, and it is still going to be faster at that point than a manual with synchros.

 

 

If those two cars have the same setup, as far as weight, HP, tires, and even a close suspension setup, I might consider that to be a good source of information that could be considered as far as the differences in lap times. If that is the case, I guess it would be pretty stupid to run one, if it is 2-3 seconds a lap slower for the best laps and for qualifying. I kind of doubt that if you swapped transmissions between those two cars that the lap times would transfer as well.

 

Given the current situation, where there aren't any of these dual clutch cars dominating in GTS, it may be best to wait and see. I do think it is coming though, and I don't see why GTS5 should not be expanded to a broader appeal for those who wish to build a car for that class, and not spend $15-20K on a transmission. At least the racing sequentials shold be equalized.

Edited by Guest

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ILIKETODRIVE
Wait a sec here, shift reductions times are not equal to laptime saved. Saving 0.3 secs in a shift doesnt drop your laptime by 0.3 secs.

Exactly. It is not a direct correlation.

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