Cars Porsche 911 Singer 1.21 (csp)

[jonelsorel]

After one lap the front tires are definitely colder in T1 than on the outlap. So that could probably explain the better stability, since the fronts grip less than one lap before.

 

[Kyuubeey]

This can be explained with more balance. We can mess around with balance-affecting suspension settings all day long. R&T drove the car as delivered I assume.

10% difference in maximum lateral grip is very easily explained with front or rear giving up prematurely.

Cool. You seem to know your stuff. I've only done this thing enough to forget how many times I have, but it seems I've been fooled all this time.

I mean, there's only dozens of variables which also explain why period cars all pull within a 0.1g range or so when tested, but ah, who cares about those. The data clearly says that a 964 Speedster on 90's tires for example is only 0.03g worse than the Singer, even if it has 1000kg more mass! With 1000kg less mass and better modern tires, I'm not surprised if we see it hit 1.1g perhaps. Amazing. Porsche really knew what they were doing, I wonder why Singer with modern semislicks barely surpasses 90's Porsche with 90's road tires.

Weissach.net - 964/993 Road Test Summary

www.weissach.net

 

[Kyuubeey]

So I got curious and brought my old C2 up to spec and corrected some stuff in the M030, and did some testing. This is with my current build, which differs a little from 0.964.

Conditions:
"Optimum" conditions in CM.
1, 2 and 3 use 964 aero, drivetrain, engine etc.
3 uses Singer mass and CoG.
4 uses all of the Singer stuff including engine and drivetrain.
1, 2, 3, and 4 all use Singer Semislick tires @ 26psi no warmers, 2nd lap out of pits.

https://www.youtube.com/watch?v=ISVRdBLV8T8

As you see, the trend is towards a slightly more neutral car the more high spec we go.
Singer sometimes turned in tighter than I expected compared to the stock cars.
Stock Carrera understeer is excessive, for legal liability reasons I would guess.
Real oversteer is somewhat difficult to provoke when driving relatively well.
Singer's main reason for the oversteer is excessive entry speed and large power compared to stock.

Basically we can determine it's mostly a driver issue, and that comparing stock 964 and Singer's car is not super useful.

 

[Robin_NL]

Balance=the car as a whole and tyres are pretty crucial as already stated.

This can be explained with more balance. We can mess around with balance-affecting suspension settings all day long. R&T drove the car as delivered I assume.

10% difference in maximum lateral grip is very easily explained with front or rear giving up prematurely.

Exactly.
On the stock setup (semis) just put spoiler to 2, both diff numbers to max(80), Front ARB to max and rear ARB to minimum.
And you will get a very very planted somewhat understeery and only on power oversteery car. You can mess up corner entrances, wank the steeringwheel and it will forgive you in general. From there on you can reduce front ARB or spoiler etc.

But above mentioned setup is boring.

It's also in the tyres as already stated. And that's a big thing.
I'm using Avo77s tyre conversion (data.acd)

If you want to test, this has my old v7 tires converted in v10
- download
- make a backup copy of data.acd in bo_singer folder
- extract in bo_singer folder
https://mega.nz/#!q1oEgYJJ!V_QF8R26JG3rLNRu3sugyrDwo-O8bF0ZHTIbQkvtueM

Disclaimer. All things are IMHO and FWIW.

@CobraCat thanks for the soundlink, greatly appreciated, sounds really oldish/mechanical!

Cheers
Robin

 

[Kyuubeey]

I'm not sure where this idea of "can't be unsettled = balanced" came from. Technically the car would be balanced if it had even slip angles at all times, or more precisely, even force from the axles at all times. So generally a bit more front slip, if your rears are bigger. In reality usually you'll want understeer, and some oversteer in some situations.

The standard Porsche spring setups come out 1.7 and 1.3hz for C2, 1.9 and 1.7 for M030 IIRC, with more front-biased ARB ratio to counter it. I also remember the RS running some very front biased setup. Singer default is 2.0 and 2.1hz in the mod, and with an even more front biased ARB setup. It's not quite balanced and you could still gain some cornering potential without giving up any actual rear grip by adjusting the balance more towards neutral, but I think with 390bhp it's alright a bit understeery.

As a sidenote, Singer recommends the AWD option for the 4.0L cars, which suggests 4.0L and RWD is not "comfortable" for most users. I find it funner with less power, myself.

 

[Robin_NL]

As a sidenote, Singer recommends the AWD option for the 4.0L cars, which suggests 4.0L and RWD is not "comfortable" for most users. I find it funner with less power, myself.

Interesting, what's in bold you can interpret it also as Singer not being confident with their setup changes (vs 964/RS OEM) , but hey that's how I read it. Sorry!

And this statement makes me believe you are doing it right with this car being as it is, with its flaws irl(no sarcasm)

Still a great little car!

FWIW
964C4 is a very planted car irl very stable and balanced and boring.....

Cheers
Robin

 

[Kyuubeey]

I think it's more a case of it being basically impossible, on road tires, to get a 400hp~ engine to not overpower the trailing arm. It's still manageable, but I bet most 964 owners have never had their car let go simply from power, and AWD could save their neck. Mind you the 993 AWD Singer uses is more oversteery and simple than the 964's AWD, so it'll probably still be fun.

The later Turbos had around 380bhp IIRC, some sources claim 400bhp. So around the same power as the 4.0. I can't remember if 964 Turbos were RWD or AWD: 993 were AWD.

Now consider below is an early Turbo car, with the way more understeery suspension and tire setup than Singer and it still oversteers on power sometimes, with something around 320bhp~ which is claimed for those early Turbo cars. Oh, and these ones also have a 20/100 diff compared to the 40/40 diffs in the C2. I've added range for 20% power and 100% coast for the next Singer build.

I'd be surprised if the later turbo cars didn't let go under throttle. Of course, let's take the worse tires into account, but it's more to illustrate that 70hp~ was enough to make the car oversteer on power given the right circumstance. Singer's 4.0 has 390 - 425bhp, so around 150bhp more than standard, or about 60% more power.

Would there be any demand for the 4.0L AWD version or the 3.8L 300bhp version?

 

[CobraCat]

I've always held the opinion of AWD on a 911 as an abomination , although I'm curious about a 3.8L 300bhp or 350bhp version.

With the 4.0L version, Singer says regarding AWD "This option is highly recommended for the high horsepower 4.0-liter equipped vehicles. "

I never knew this until you posted it above. I wonder if Singer makes the buyer sign a waiver if they opt out of AWD on the 4.0L version ?

Perhaps in the future consider a AWD 4.0L version and a 3.8 300bhp version. I think Ben still has a 3.8L badge laying around.

 

[Robin_NL]

I think it's more a case of it being basically impossible, on road tires, to get a 400hp~ engine to not overpower the trailing arm. It's still manageable, but I bet most 964 owners have never had their car let go simply from power, and AWD could save their neck. Mind you the 993 AWD Singer uses is more oversteery and simple than the 964's AWD, so it'll probably still be fun.

The later Turbos had around 380bhp IIRC, some sources claim 400bhp. So around the same power as the 4.0. I can't remember if 964 Turbos were RWD or AWD: 993 were AWD.

Now consider below is an early Turbo car, with the way more understeery suspension and tire setup than Singer and it still oversteers on power sometimes, with something around 320bhp~ which is claimed for those early Turbo cars. Oh, and these ones also have a 20/100 diff compared to the 40/40 diffs in the C2. I've added range for 20% power and 100% coast for the next Singer build.

I'd be surprised if the later turbo cars didn't let go under throttle. Of course, let's take the worse tires into account, but it's more to illustrate that 70hp~ was enough to make the car oversteer on power given the right circumstance. Singer's 4.0 has 390 - 425bhp, so around 150bhp more than standard, or about 60% more power.

Would there be any demand for the 4.0L AWD version or the 3.8L 300bhp version?

Turbopower comes with (sudden) torque at given rpm.
The 390-400HP Singer engine is not a savage/angry engine at all.
(Also ingame) .

It's Singer's real life setup what does have flaws I guess.

RUF's BTR/CTR in real life are probably not good examples but they got their facts together in general vs Singer.

IMHO!

Cheers
Robin

 

[Kyuubeey]

Dunno, looks peakier than standard M64s to me.

 

[Robin_NL]

That BM movie is awesome. It's power oversteery but also pretty understeery. The car is sprung/dampened soft which is very good at the NS. My current real life car is a bit too bouncy there, I almost lost it a the downhill PG II last april(VLN layout)



Cheers
Robin

 

[Robin_NL]

View attachment 333408

Dunno, looks peakier than standard M64s to me.

Yep, but it's not turbotorque grunt.

Cheers
Robin

 

[Kyuubeey]

If you're full throttle for any extended period, it really doesn't matter at all. These cars don't really have any true turbo lag like say the 930.

Kilowatts are kilowatts and it doesn't matter how they're generated: apart from turbo pressure not being constant, so I guess you'll have some minute variation IRL, when NA would be smoother.

 

[Robin_NL]

If you're full throttle for any extended period, it really doesn't matter at all. These cars don't really have any true turbo lag like say the 930.

Kilowatts are kilowatts and it doesn't matter how they're generated: apart from turbo pressure not being constant, so I guess you'll have some minute variation IRL, when NA would be smoother.

Kilowatts are Kilowatts but they are not Nms
Nm's make tyres spin. Period.



Cheers
Robin

 

[mclarenf1papa]

Technically the car would be balanced if it had even slip angles at all times, or more precisely, even force from the axles at all times.

That's not what "balance" means from a vehicle dynamics perspective, ever.

Anyway, not to play devil's advocate, but the behavior in the Black Cat County videos looks exceedingly unlikely for a production car. Additionally, it looks to behave a good bit differently in the laguna hotlap than in AC.

 

[Kyuubeey]

That's not what "balance" means from a vehicle dynamics perspective, ever.

Anyway, not to play devil's advocate, but the behavior in the Black Cat County videos looks exceedingly unlikely for a production car. Additionally, it looks to behave a good bit differently in the laguna hotlap than in AC.

Sure, "balance" means varying degrees of understeer to just about anyone. Which is what we already have: just a bit less than on a stock 964.


I didn't know leaked footage of the car driving on the slicks I made for it in AC got out. Someone must have access to my HDD. Could you send me that footage so I can compare it to the Laguna Seca video? You know, because it's on slicks in the video and not semis.

 

[mclarenf1papa]

Sure, "balance" means varying degrees of understeer to just about anyone. Which is what we already have: just a bit less than on a stock 964.


I didn't know leaked footage of the car driving on the slicks I made for it in AC got out. Someone must have access to my HDD. Could you send me that footage so I can compare it to the Laguna Seca video? You know, because it's on slicks in the video and not semis.

I can pretty well guarantee the real tires (irrespective of compound/construction) have more than a 1.1% grip difference at nominal loads front to rear (that yours have). ~20% width difference means a lot more than that. For the record, the P13's tires (3% width difference) have a larger grip distribution than that.

Could do with losing a bit of the attitude.

 

[Kyuubeey]

I can pretty well guarantee the real tires (irrespective of compound/construction) have more than a 1.1% grip difference at nominal loads front to rear (that yours have). ~20% width difference means a lot more than that. For the record, the P13's tires (3% width difference) have a larger grip distribution than that.

Could do with losing a bit of the attitude.

I don't know what tire set you're talking about, but I'm going to assume semis. I think so too, which is why I've made the difference larger for the next version. What kind of % split do you think is in the ballpark?

I just found it a bit funny how you're comparing a car on semis and a car on slicks as a basis for argument. Most the power-oversteer issues go away if you can't get wheelspin even when you're full throttle with wheel turned. I thought it'd be kind of evident.

 

[mclarenf1papa]

I don't know what tire set you're talking about, but I'm going to assume semis. I think so too, which is why I've made the difference larger for the next version. What kind of % split do you think is in the ballpark?

I just found it a bit funny how you're comparing a car on semis and a car on slicks as a basis for argument. Most the power-oversteer issues go away if you can't get wheelspin even when you're full throttle with wheel turned. I thought it'd be kind of evident.

Not power oversteer that’s the problem.

Anyway, it depends. Certainly well upwards of 5%. Refer to the Z06 tires I did with Jason as an extreme example of unequal grip distribution. In any case, I’m still not entirely sure why you use KS load sensitivity as a basis.

 

[Kyuubeey]

Not power oversteer that’s the problem.

Anyway, it depends. Certainly well upwards of 5%. Refer to the Z06 tires I did with Jason as an extreme example of unequal grip distribution. In any case, I’m still not entirely sure why you use KS load sensitivity as a basis.

I probably should make some tools to generate curves for AC's format. I'm curious, are you using an app to look @ the tire grip or just calculated it?

PS: Z06 doesn't have load curves in the folder, but the other cars do. I guess that's Jason's matter.