Spiny's ALS Spec Porsche 911

[Spiny Anteater]

Go on, you know you want to run one really 



So, anyways, here's the spec that I've been running. It's pretty good for a 911 so long as you don't go hitting the grass or kerbs, just got to keep it on the road and away she goes:

Stats:
361 bhp, 293 lb/ft, 2091lbs

Upgrades:
Power: Stock engine, every race upgrade except stock fuel system
Handling: Race everything except stock brakes and weight reduction
Wheels: Michelin Slicks, stock width, rim and rim size
Aero: None

Tune: (F/R)
Tyres: 29/28
Gears: FD = 3.85, 1-6 = 2.89, 1.99, 1.51, 1.23, 1.06, 0.94
Camber: -0.9, -0.7
Toe: 0/-0.2
Caster: 5.5
ARB: 9.70/14.46
Springs: 256.1/354.5
Ride Height: 7.2/7.2
Damping: 5.6/8.0 (Rebound), 2.8/4.0 (Bump)
Diff: 53% Accel/ 28% Decel

[Drift2XL]

Alrighty now, I finally had a chance to get to the 911.

Your set up was worth a 1:52.523 on a light build with only 306HP.

I came back with my first tune  1:52.109. And here it is.

30/30     tire
-1.3/-1.1 cam
0/.2       toe
5.5       cast
10.3/9.0 ARB
210/367 spring
4.9/8.0  reb
2.8/3.9  bump
40/30    diff

Now, the only thing I don't like about mine is the nose takes some time to turn in. You need to lead it like a muscle car. And its a little hairy during hard braking in rough patches.

It does turn really well on throttle, on exit. If you can get the lead right on the steering, it will come off hard. 

I think that a compromise set up between the two would yield best results. I looked at the tire temps during the run with your set up, and the LF tire's outside was almost 15 deg. hotter than the middle. So I would say more camber would really help out.

I have a belief that the slicks have a softer sidewall than the sports. I can feel the tread squirm under high DF. It know that slicks need more camber than DOT's. I have tuned up an S7 R2 with the same alignment settings as the street cars I was running. The inside temps on the street cars were alot hotter on the inside. The S7 had an even spread of no more than 5 deg.

I hope some of this helps. I really think that adding camber would drop off more time. I'm just sorry that it took me four days to get some time to run it. It is very stable and predictable, for a 911.

[Blooze]

I thought I'd give this a try, to use a base for my 'speriment with the Wb Tuning on RR cars.

I built the car exactly to Spiny's specs and ran it out to Maple Valley short which I am wont to do with new and unfamiliar cars.  The 42% weight bias, 5.5 Castor, and -.2 led me to believe that the car might have issues with turn in and push.  For me, it did.  I consider most of this difference in driving habits.  We are seeing a lot of that as we get more people who are comfortable with their own tuning in here.

"How come you got this set like that?"

"Cuz that's how I like it."

And no further explanation is required.

Now my real purpose is to see how this type of car, in this class behaves with the ole 54.5% Wb build.  This will probably take place in two increments.  The first will be to apply the tuning to the configuration as it is listed.  The second will be to configure the car more to my taste?  liking? proclivities?  whatever.  The act of moving these cars up into A class sure does bring the different strokes thing to a head...

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[Spiny Anteater]

I built the car exactly to Spiny's specs and ran it out to Maple Valley short which I am wont to do with new and unfamiliar cars.  The 42% weight bias, 5.5 Castor, and -.2 led me to believe that the car might have issues with turn in and push.  For me, it did.  I consider most of this difference in driving habits.  We are seeing a lot of that as we get more people who are comfortable with their own tuning in here.

I think a lot of this is to do with me starting with Feuerdog's calculator. Having said that, afficionados of 'dogs calculator will see that I did soften the stiffen the front ARB very slightly to balance the car slightly towards understeer. It seems that I do prefer an understeering car - probably due in a large part to me having owned mostly FWD's in real life. No coincidence either I suppose that when I tried skid training that I was much better at controlling understeer than oversteer (which probably puts me in the same group as 95% of the population).

Got to say I'm intrigued by Drift's set-up with it's 36% bias to the front. I'm going to guess that if I put that on the 911 and run it next to mine that it will feel very twitchy and oversteery. Something tells me that's something for the weekend 

I'll also give the camber a try too. Again 'dog followers will notice I added a bit to the front camber - as Drift saw the outside of the FL tyre does heat up mquite a bit more than the inside. I don't recall 15 degrees (more like 10) but I suspect that again boils down to driving style. (Also, is that really +0.2 toe that you're running there?)

Anyway, thanks for your input guys. That's the great thing about these boards - you know you'll get intelligent replies.

[bimmerlovere39]

The 42% weight bias, 5.5 Castor, and -.2 led me to believe that the car might have issues with turn in and push.  For me, it did. 

Blooze... not to pick on ya, but how much time to you usually spend driving 911s?  They require a whole different driving style from other cars.  You've got to use throttle and brakes to get the weight to the front to get a strong turn-in, but then they can really hook up coming out.  That's the main advantage to the rear engine is the traction (that's why they start so well).  It also makes Porsches excellent high-powere RWD cars.

Anyway, I'll have to try this out after I finish Halo

[Blooze]

You're quite right Bimmer, but I thought that with my wizardry and genius I could tune that out of the little car.  Today has been quite frustrating.

I wish that I could trade the car in for a dog.  I would take the dog out back and shoot it in the ass with a shotgun.  Something has to scream, something has to bleed.

The 54.5 tune is quite tractable except for the turn in and push issues.  I suspect that it is something to do with the drive type flag.  I tried every possible combination from a classic RR build to a 57% build trying to get the damned thing to act like it had some weight on the front wheels.  Adding the front spoiler did no good.  I have managed to get so it isn't so severe, mostly by taking steps to loosen up the rearend.

The car does quite well actually - it is within a few tenths of my top 500 GS ghost on Maple Valley II,  and the same with my top 1000 time with the VIS on Tsukuba.  This is a commendable and above average performance.  However, I feel I see and feel that the car could clean the other car's clocks, IF I could just......get.......it to turn.

Argggg. 

I suspect that a major piece of the problem is me.  But I don't know if I want to upset the apple cart so severly to become a good Porsche driver.  And then spend time unlearning the Porsche habits to drive something else.

Where's my shotgun?  Maybe I'll shoot it anyway...

  $

[Hoplee]

I had all the turn-in I wanted when I put the front wing on the 911. I wound up setting front df to zero to get it back under control! I would've just taken the thing off but I need it to run slicks in B-Class...

[Hekalite]

I will post my Maple Valley Short setup when I get home.  I actually tired racing with it on Wednesday night in an Exodus room and I discovered that if I don't hit the sweeper just right, it's very bad.  I may try to tune out the sweeper problem, but I don't recall having any turn-in problems.  I think I may lift a little to get it to turn, but it's a very fast car on the short track.  And I don't find that it needs nearly as much maintenance throttle as the 914/6.

[Blooze]

I re-examined what I was doing with the front spoiler - I had it set to zero.  I considered that I had added the rear bumper and in a somewhat calculated guess, assumed that the rear downforce supplied with the rear bumper was neutralizing the downforce at its base setting (45), and upped the setting to 68.  That seemed to help.  I was able to run a 38.877 on Maple Valley, which is my third fastest time on the track and by my guestimation, a top 1000 time.

I also re-examined my turn in issue.  I concluded that it wasn't turn in so much as it was that the car would not rotate on turn in and therefore I found myself waiting on it before I could start up with the throttle.  Funny thing was, while set at the Replay Menu I could hear the AI doing the same thing as it chauffered my car around the track.  I was curious about Drift's positive rear toe setting in his setup - I think I will see if a click or two there will help... I already have it at zero trying to cure this thing.

It might be worthwhile to note that I have been able to come fairly close to the bench mark numbers of Spiny's build with just 317 Hp - leaving quite a few PIs to use for upgrading tires, brakes, and dumping some poundage - resulting in a G @ 120 value of 1.15.  I still have some twiddling to do with the transmission and will provide a full setup report when I have it sorted out.

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[Hoplee]

I normally drive my little civic at the autocrosses but a friend came by with a vintage 911 so I had a go in it.

First Impression: Once I put on a helmet, there are very few cars I can fit in!

Second Impression: It's just a car

The sights, the sounds, and for me, the smell of a Porsche are pure excitement. However, on the track it was just another car. It really wasn't all that different from driving the Honda, as long as you're at 9/10ths. When you push it to 10/10ths however, it starts acting more like my old IH Scout on a patch of ice. The rear end needs you to make a good decision and stick with it. If you're the kind of driver whose default behavior for any unexpected results on the track is to back off, the 911 won't work so well for you. Same thing with the Scout on a patch of ice, or that Miata I used to raise hell on the loose dirt of central Florida.

Off-throttle oversteer happens in a lot of cars in different types of situations. I really don't think the 911 is all that unique in this respect.

As to the in-game behavior of the 911, I'm not having too much trouble with it, at least nothing like the Yellowbird from GT4. I am experiencing some transitional instability if the exit drift of one turn leads right into the entrance drift of another turn. It makes corrections tricky, usually leading to an inside off followed by an outside off.

Like Blooze, I'm still thinking about that front df setting

[bimmerlovere39]

I guess if I don't play Halo as soon I get home, I might adapt me C-Class 911 to A-Class, then post el setupo

[Hekalite]

Wow, I should really pay attention.  I thought we were talking B-class 911 settings here and when Blooze said 38.877 on maple valley I was all like  .

[Blooze]

...If you're the kind of driver whose default behavior for any unexpected results on the track is to back off, the 911 won't work so well for you...

Aye, there is the rub.  I am not that sort of driver.  A lifetime in the Colorado Rockies will teach you that.  My tendency when trouble comes is to grab a gear and hit the gas... and that is where me and the 911 are running afoul of each other.  If I don't have it pointed somewhere down the track when I do my stomping, we are going off track.  I think I have most of the throttle up oversteer out of it, as well as the off throttle oversteer, but damn does the thing push when I nail the gas.  That is sort of what I meant by waiting on it...  too much throttle to soon in the turn has you headed off track and the only option is to lift and get some weight back on the front tires.

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[Hoplee]

D'ya think the weight transfer front to back is the problem? Sounds like dampers to the rescue!

[Blooze]

I imagine I could give my "Front Exit Grip" damper agent - - another tap.  I don't want to go too far with it else my set up start looking like one of FDawgs...

What I'm looking for really is for the thing to change the direction in which it is pointing quickly without me having to resort to managing throttle up oversteer to do it.  That is a crap shoot on its best day...

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