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Old 12-17-2018, 10:27 AM
  #61  
Gary R.
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Originally Posted by Carrera51 View Post
Given that the 996/997 and 987 plus the current rules have basically killed the 993 as a G or H car, I think you should consider allowing the 993 into this class so it has a home where it could be competitive since as we all know, it is the last of the air cooled cars.
Knock the D Stock weight down to "as low as you can get it including driver" and I may come back!
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Old 12-17-2018, 12:07 PM
  #62  
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Originally Posted by Gary R. View Post
I can see it now, 3500 lb. 250 HP 964s racing with 2700 lb 185 HP D class SCs, don't know why it wasn't always this way!
Originally Posted by tcsracing1 View Post
I would say remove the 964 and 993. The coil spring and ABS is too far advanced for the earlier cars.
Originally Posted by 993944S2 View Post
The more models that you include the more complicated the BOP calculation becomes. To keep things simple the primary way to balance power will be to add/subtract weight. I don't think people would enjoy driving a 993 with 400 lbs of lead where the passenger seat was.
Will be interesting to see what the actual proposal is. I don't have a lot of races under by belt but enough on track w/ F 964s and E 911s to have an idea of what would need to happen knowing there never is or will be a perfect solution to leveling the playing field in non-spec (to include GTC) classes. PCA stock class is not spec- and there strength and weaknesses of different models.

My previous wish-list was just that and do think weight adjustments can level out the playing field some. 3.2s will have a big (!) gearing advantage w/ 15s but 964s will have better suspensions and brakes and 993s better suspension, brakes and fuel injectors than the 964. 964s in the boot at the Glen are f'g miserable - too fast for 2nd and at around 62-ish mph the tach is around 4k-ish and lugs badly. A E 911 on 15s would probably pass a well driven 964 up the toe right now w/ current weights but of course the 964 will win a drag race down a straight out of 80 mph corner w/ similar drivers.

That said, I think more realistically it would be better to include D&E A.C. cars together and F&G A.C cars together which for the most part would just be convincing F 964 owners to remove 271#s from their cars. Before Clark's post I had been thinking about this over the last few years anyway which was a Spec 964/993 class which would mostly keep stock class rules with a few changes.

But....even though the numbers are small in G at most races the racing is very good and although I haven't raced Anthony in his Cayman yet I watched him and Omar go at it at Summit and they looked very close car-wise and was great racing between completely different platforms so stock class PCA does do a good job with this overall. It does work although it will never be perfect and they have said that in the past (something like PCA stock is a home for every P car sold in the US but there will be some models more competitive than others).

I'm hoping and planning to get back to G for at least a few races this year. Even though the numbers are small I do like G and also really like my car at the current weight of 2,910 with driver.

Dear F 964 racers, please drop 271#s and come race us in G.

Last edited by forklift; 12-17-2018 at 02:01 PM. Reason: clarity
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Old 12-17-2018, 08:33 PM
  #63  
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Originally Posted by Gary R. View Post
Knock the D Stock weight down to "as low as you can get it including driver" and I may come back!

Just need to hollow out the wheels...
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Old 12-17-2018, 09:15 PM
  #64  
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Hard to keep racing the air cooled cars at the current values. This seems like a decent attempt, but if you narrow down to just a few classes, I doubt you’ll get many takers.
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Old 12-17-2018, 09:17 PM
  #65  
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Keep it simple stupid.
That's my motto.

911CUP (911 D, E, F & G stock cars thru 964 only)
* No changes to stock letter class rules except weight
* 911 cars up thru 964
* One (1) spec tire Hoosier R7
* Free tires for winners at 5 select races
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Old 12-18-2018, 12:22 AM
  #66  
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Originally Posted by GT3DE View Post
Keep it simple stupid.
That's my motto.

911CUP (911 D, E, F & G stock cars thru 964 only)
* No changes to stock letter class rules except weight
* 911 cars up thru 964
* One (1) spec tire Hoosier R7
* Free tires for winners at 5 select races
Clark, Why no 993???
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Old 12-18-2018, 01:08 AM
  #67  
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I'm all for less classes and this would be great for the air-cooled 911 drivers but what happens to all of the E and F class Boxsters? The numbers keep increasing as air cooled cars decrease but I don't think the numbers are there yet to have classes of their own.
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Old 12-18-2018, 05:35 AM
  #68  
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Originally Posted by Texas RS View Post
Clark, Why no 993???
What 993's ?! There aren't any. Elvis left the building a long time ago.

I was already stretching the concept adding 964. The 993 is too different - suspension, brakes.
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Old 12-18-2018, 05:42 AM
  #69  
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Originally Posted by sbelles View Post
I'm all for less classes and this would be great for the air-cooled 911 drivers but what happens to all of the E and F class Boxsters? The numbers keep increasing as air cooled cars decrease but I don't think the numbers are there yet to have classes of their own.
944's checked out already to their spec groups.
Let the Chixsters do their own thing. Don't they have their own spec class(es) anyway?

I'm trying to save the old school 911s in pca. These things are disappearing, less and less every year. Need to do something to reverse the trend.
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Old 12-18-2018, 02:17 PM
  #70  
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Default Sent you a text.

Clarke, I called you regarding this. Call me back.
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Old 12-18-2018, 03:22 PM
  #71  
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If you make these race classes too broad, the whole system falls apart as you can no longer BoP the various cars for the majority of tracks by weight alone. So focus on just ‘77 - ‘88 911s.
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Old 12-18-2018, 03:41 PM
  #72  
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Nice idea. One thing to consider is using real world HP numbers when doing BoP. Factory numbers listed in rules book are a bit off based on reality. 84-86 E cars for example are supposed to be 2779 weight, 207hp at crank, with a power/weight=13.43. Aren't motors really putting out 220-230 at the wheel. Using 1.15 drivetrain loss, that's about 260hp at the crank, making p/w 10.6. (a solid G class p/w) 964 motors and others are also making more than listed as well. Something to think about to try and make level playing field.
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Old 12-18-2018, 08:25 PM
  #73  
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The following is just MY OPINION as an overly cerebral engineering type

Basing BOP on advertized hp to weight(measured or otherwise) or barring 993 because it has a more complicated rear suspension is a canard.

Things that affect performance the most are
1) torque curve, both magnitude and shape, hp is just the result of having torque at higher rpm

2) gearing(which includes tire diameter), this multiplies engine torque and translates the circular motion of the output shaft into push or thrust

3) weight, obviously the less weight the more all aspects of track performance are improved

4) aero, the faster you go the more important this is

How the suspension connects to the pavement is a really minor consideration given that suspension travel is severely limited by the use of high motion rates on whatever suspension is used.

There is a major difference in the potential performance that can be pulled from a water cooled vs an air cooled and I agree that these air cooled cars need a venue separate from the newer water cooled ones. Also the performance potential of a wide body like a 930 vs an SC/Carera is difficult to quantify

Rules should keep stock or at least close to stock aero and gearing, tires free(but w/ compensation made for varying ODs), brake upgrade and weight(including driver and 1/2 tank of gas) compensation added/subtracted, stock type suspension w/ stock attachment points otherwise free(there is an $ argument for limiting the shocks to non adjustable but then the side issue of revalving enters too)

given the above it shouldn't be hard to equalize everything from a '73RS clone to a 993 Cup clone or anything in between
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Old 12-18-2018, 09:40 PM
  #74  
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As in NASA, a dyno is essential to all this IMHO. And to flush out the inbred cheaters, a dyno at the track is required also.. Anyone can have their car dynoed, then change cams and ECU to a previous setup, and go race. At the Glen guys in E are hitting well under 2:10's when the fastest D car was squeaking under a 2:13 (wasn't me, I was well above that). I'm not sure a D car can compete but maybe 150-200 lbs will make the difference. It's going to come down to weight/HP/Driver and that's what NASA has been selling for a while.
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Old 12-18-2018, 09:52 PM
  #75  
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Originally Posted by Gary R. View Post
As in NASA, a dyno is essential to all this IMHO. And to flush out the inbred cheaters, a dyno at the track is required also.. Anyone can have their car dynoed, then change cams and ECU to a previous setup, and go race. At the Glen guys in E are hitting well under 2:10's when the fastest D car was squeaking under a 2:13 (wasn't me, I was well above that). I'm not sure a D car can compete but maybe 150-200 lbs will make the difference. It's going to come down to weight/HP/Driver and that's what NASA has been selling for a while.
My experience is that 100lbs is worth roughly 1.5 seconds at the Glen.
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