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JSG1901

DISCUSSION CLOSED: Add a factor for sequential gearboxes

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JSG1901

NOTE: Two different suggestions were made on this topic. Both have been included below.

 

Type

Proposal for a new rule

 

Existing rule section (if applicable)

 

 

Proposed change

Modification factory for Sequential gearbox

 

Reason

Keep "specialized automatic" gearboxes from creating class spread.

More aligned with Super Touring for easier crossover.

 

Proposed new wording

Dog-ring/straight-cut gears (non-synchromesh transmission),

and/or sequential/paddle shift/semi-automatic, subtract 0.2 = ____________

(no assessment for automatic transmission utilizing a torque converter)

 

--------------------------------------------------------

 

Type

Proposal for a new rule

 

Existing rule section (if applicable)

None

 

Proposed change

I think there should be a system to equalize people with the SMG transmission.

 

Reason

There is an unfair advantage in speed shifting

 

Proposed new wording

Maybe an added value to the denominator of the HP to weight ratio?

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vwmann1

I agree with the rule, but I feel that the .2 is not enough of a penalty for our rule set. Understandably, there is a need to keep the rules the same across classes, but to just use what other classes are using is shortsighted. The rues for st/str break down the hp/wt calculation much finer than we do. If you total the time savings per lap and compare those numbers to standing class records for the normal 2-3 mile race track it is closer to a total class jump. I feel there needs to be more research done to come up with a more realistic multiplier.

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thehounder
I agree with the rule, but I feel that the .2 is not enough of a penalty for our rule set. Understandably, there is a need to keep the rules the same across classes, but to just use what other classes are using is shortsighted. The rues for st/str break down the hp/wt calculation much finer than we do. If you total the time savings per lap and compare those numbers to standing class records for the normal 2-3 mile race track it is closer to a total class jump. I feel there needs to be more research done to come up with a more realistic multiplier.

 

How are you calculating the time savings per lap exactly?

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Eliminator

I'm in accordance. Although I hate to limit technological advancements, I don't think this one is derived from creativity and inginuity. ... unless one machines his/her own. For $20K you can buy this advantage. I suppose it's inevetible, but for now, I think the rule will keep competitors stacked closer together... and spare the wallet for the others!

D. Pedri

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thehounder

My questions is, "are all sequentials the same?" There is no way that an SMG is as fast as a DSG or a PDK or a drenth. I think that there is a benefit to multi clutch boxes where there is no power interruption, but for single clutch boxes, there should be no measurable differences. In fact based on testing done by European car (April 3, 2009) it shows that the SMG is actually slower in the 3-4 shift than the manual, while being slightly faster in the 2-3 shift.

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Eric W.

I disagree on this one. Mainly because how do you know what system is worth what mount of time to dictate the "factor"?

 

It'd make impound a nightmare trying to figure out who has what and what needs to be modified, etc.

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abad46
My questions is, "are all sequentials the same?" There is no way that an SMG is as fast as a DSG or a PDK or a drenth. I think that there is a benefit to multi clutch boxes where there is no power interruption, but for single clutch boxes, there should be no measurable differences. In fact based on testing done by European car (April 3, 2009) it shows that the SMG is actually slower in the 3-4 shift than the manual, while being slightly faster in the 2-3 shift.

 

Don't forget about the extra weight the E46 SMG system already carries. IMO it is already penalized. It, without a doubt, should be exempt from this discussion.

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thehounder
I disagree on this one. Mainly because how do you know what system is worth what mount of time to dictate the "factor"?

 

It'd make impound a nightmare trying to figure out who has what and what needs to be modified, etc.

 

I could write it all on the back of a postage stamp...not that many variants.

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Eric W.
I disagree on this one. Mainly because how do you know what system is worth what mount of time to dictate the "factor"?

 

It'd make impound a nightmare trying to figure out who has what and what needs to be modified, etc.

 

I could write it all on the back of a postage stamp...not that many variants.

 

And you know how much time each is worth on any given track at any given time and for each type of car?

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John Graber

I would support the rule. Would probably need some help detailing it, but I like it in principle. Also, Super Touring has a similar mod factor.

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Luke P.

For.

 

I'm not trying to play on this level. Sorry for those SMG types, sell your system to someone who needs it for the street and convert the racecar to manual. It's not extremely complex to do and from the sound of it, it'd be a benefit.

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UKRBMW

For

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Michael G.

Before we decide on penalizing the gear boxes we need to see if there is actually a problem - as far as I know, there are very few if any cars with real race gear boxes competing in GTS now, and none actually winning. The issue of street SMGs was discussed in details before and agreed, that no advantage found there too (those are not build for racing - overheat quickly, go to limb modes and actually slower often).

The bigger issue is the Pandora box effect. GTS was built as an "open rule" series, where only major, well documented advantages are penalized, like weight, HP and racing slick tires. If we will decide to extend this to other features - we need to have very clear and overwhelming evidence. Otherwise, we might as well begin to discuss penalizing suspension, aero, fuel cells, wide body kits, big brakes etc. Before we know it - we might as well convert to 40 page Rules of PT/TT.

I am against the proposed penalty, since no hard evidence of advantage seen yet and will contradict with the philosophy of the GTS series.

 

Michael G.

NE GTS Dir.

Edited by Guest

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mikew968

There is no one winning with any of these transmissions at this point let alone a way to determine any suspected advantage. As far as the PDK call Jack Baldwin and ask him if he close a 6 sp or a PDK even though World Challenge offers no penalty for the pdk. I can tell you he choose a 6 sp. There is a lot to figure out at this point and no one know what the outcome will be.

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autodoctor911

I would suggest that Dog-gear H-pattern racing gearboxes and older BMW SMG transmissions be left out of any penalty class, as from driving these, I don't see any real lap time advantages. There is definitely more to be gained with ratio changes than the shifting operation of these transmissions.

 

As for PDK or DSG, IDK. I would think these, along with any other newer dual clutch or fast shifting automated manual would have pretty close to the same acceleration advantage as a full sequential manual race box, which definitely will give faster shifts, and quicker lap times. I think the .2 handicap would be a good place to start for at least the full sequential race transmissions, as found on newer Porsche Cup cars, etc. If they start to dominate even with the .2 handicap, then more could be considered.

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Michael G.

Should we wait to see if any of those actually dominate before considering penalties?

On the other hand, we know, big brakes and good aero makes cars go faster, as well as good triple adjustable shocks - why don't we penalize this as well then?

 

Michael G.

NE GTS Dir.

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911.racer

I am torn on this one.

 

On one hand, I would like to see us keep the rules as simple as possible.

 

On the other hand, a true sequential, like the 997 cup cars or the Cayman PDK systems are a real advantage and .2 is not much of a penalty.

 

Ultimately, I think that I land on KISS.

 

Against.

 

Ed

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jvanhouten

For.

 

I agree that there isn't much of a problem, yet, but it is coming and for those considering an aftermarket gearbox, they should know the potential penalty before spending the $$$$.

 

The way I see if, there are two distinct advantages to an aftermarket gearbox--reduced shift time and increased in usable gears. I'd love to knock .25+ seconds of off throttle time on each shift--that's obviously a huge advantage. I'd also argue that moving from 3 to 5 usable gears is as much an advantage as the reduced shift time, if not more of one. There seems to be aftermarket support in the Porsche world for gearsets to fit stock boxes, but there isn't much in the BMW space.

 

The extra weight argument for SMG doesn't hold IMHO as it is 18lbs, the equivalent of 3 gal of fuel.

 

Maybe there should be three levels--one for stock H-pattern, one for SMG, et al, one for aftermarket sequential/DSG to account for both the gearing and shift time advantage. The rub is coming up with the assessments should be.

 

For reference on shift times, here's something I posted in the discussion last year:

 

=================

Some more data for the discussion from "Analysis Techniques for Racecar Data Acquisition" by Jorge Segers on pg 54, Table 6.3.

 

Typical upshift times for various racecars:

F3 car: 0.15 sec

Porsche 911 GT2 Turbo, synchro H-pattern: 0.35 sec

Dodge Viper GTS-R, synchro H-pattern: 0.32 sec

Dodge Viper GTS-R, sequential no powershift: 0.23 sec

Dodge Viper GTS-R, sequential with powershift: 0.18 sec

LMP1, sequential paddle shift: 0.10 sec

 

For current gearboxes out there, mostly from manufacturer literature and/or Wikipedia

VW DSG: 0.008 sec

BMW SMG II (E46 M3): 0.080 sec

BMW M-DCT (E92 M3): 0.080 sec

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kbrew8991

Some guys run an SMG car because they *have* to due to a disability - would hate to see them get handed ballast over it. Hopefully you guys find a good way to select the transmissions that may warrant a bit of extra weight without writing something so broad as to put extra weight on everyone without 3 pedals.

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jvanhouten
Some guys run an SMG car because they *have* to due to a disability - would hate to see them get handed ballast over it. Hopefully you guys find a good way to select the transmissions that may warrant a bit of extra weight without writing something so broad as to put extra weight on everyone without 3 pedals.

 

But the intent would not be to penalize those cars but to make equivalent given the advantage that SMG has.

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abad46
Some guys run an SMG car because they *have* to due to a disability - would hate to see them get handed ballast over it. Hopefully you guys find a good way to select the transmissions that may warrant a bit of extra weight without writing something so broad as to put extra weight on everyone without 3 pedals.

 

But the intent would not be to penalize those cars but to make equivalent given the advantage that SMG has.

 

The SMG in an E46 already is penalized with the extra 25lbs it carries around as well as the fact you cannot run a lightweight flywheel or multi-disc clutch.

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JSG1901

For the record, at the 2013 NASA Championships, GTS5 was dominated by sequential-gearbox Cup Cars.

 

And, having spent more than my fair share of time at that event standing next to the dyno as we ran GTS cars through, I can tell you the speed with which the Cup Cars upshift is absolutely astonishing. There's really no other word for it. There's no discernable break in power and they just go bangbangbangbang up through the gears faster than you can imagine. Our race director made an effort get there in time to watch the Cup Cars dyno just so he could experience it, too.

 

I have resisted adding a factor for these gearboxes in the past, but having now stood three feet away from one and heard and seen it for myself, there's no question in my mind that that gearbox provides an advantage. How much of an advantage, I don't know, nor what other gearboxes provide a similar advantage. My personal experience with BMW's SMG box in street cars I've driven tells me it does not provide an advantage because it kinda sucks, but the newer BMW boxes and the Porsche PDK absolutely do not suck and almost certainly DO provide some kind of advantage. Whether it's enough to penalize, that I can't say.

 

But those Cup Cars? That's a whole 'nother deal and, well, damn.

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bmwjoon

The weight of the system is already counted in the weight of your car so that isn't a valid argument.

 

I agree with some factor for true sequential gearboxes but I have to admit after driving SMG gearboxes (only on the street) for a number of years it's a wonky system so I understand why guys feel like it's not an advantage.

 

Couldn't we just write the rule as "if you use these listed gearboxes: drenth seq model #'s, quaife seq model #'s, xtrac etc. etc you must add a factor of .2"

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ILIKETODRIVE
Couldn't we just write the rule as "if you use these listed gearboxes: drenth seq model #'s, quaife seq model #'s, xtrac etc. etc you must add a factor of .2"

As an outsider looking in this seems to make a fair amount of sense.

 

(Simon - who crewed with Magnus at the 2010 24 Hours of Daytona so I know where you're coming from Scott Good)

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