Low Grip Cobras, What Gives?

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LS Chiou

LS Chiou

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In road car category, there're two Cobras in GT6: AC 427 S/C '66 and Shelby Cobra 427 '66.

I love them both for style, sound and heritage. But I'm totally baffled by how they drive.

They are both pretty light and small, coming with healthy f/r distribution, and equipped with relatively fat tires, but why they grip so bad?

It seems very difficult to find any other cars (in similar size and weight) which have less grip and handle worse.

Any idea?
 
LS Chiou
In road car category, there're two Cobras in GT6: AC 427 S/C '66 and Shelby Cobra 427 '66.

I love them both for style, sound and heritage. But I'm totally baffled by how they drive.

They are both pretty light and small, coming with healthy f/r distribution, and equipped with relatively fat tires, but why they grip so bad?

It seems very difficult to find any other cars (in similar size and weight) which have less grip and handle worse.

Any idea?
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Best guess is PD is simulating the old school tires and suspension of the era.
 
Read the wiki, and watch some videos on how unmanageable this car is on amateur hands...
one of the first racers that drove this car nicknamed it the turd, its a combo of weak chassis(designed firstly for 6cil engines) too much power, bad suspension stlyle, short wheelbase, you name it...
 
Yeah I've seen them spin over the youtube.

Still curious how PD simulate it.

After the chassis being reinforced, suspension being stiffened and lowered, tires being upgraded, it still doesn't grip. The dive, squat and rolls are much reduced after tuned. And the tire size looks pretty generous. But wherever it goes, it slides. I almost talk to it, "Argh~ do you have to.... ?"

Oh well, it's a snake, so it gotta have a slippery belly, is that it?
 
Is your loss of traction under acceleration?

I took a spin around Willow Springs to see what you meant, and yes they're a bit squirrely at times, but only under acceleration and aggressive turning. It seems the problem is the Cobra's high power and low weight. The rear tires just want to turn and the car is just not heavy enough to allow that efficiently.
 
I feel it not only in acceleration, but all directions -- the braking distance is long, the cornering limit is low. Slow reaction to steering correction, and with a final snappy bite.

Simply put, it seems the tire is in some lower grade than it's shown. And the behaviors of suspension & chassis are so awkward, even after stiffened (already limiting the travels and weight transfer).

The peaky power delivery and tall gearing don't help, of course. So a fully adjustable transmission makes it much smoother especially at the exit of low speed corners. (sadly that transmission whining somewhat pollutes the magnificent exhaust note)

I drive without assistances, so I can use the throttle gingerly (limiting the torque output), the spin under acceleration can be largely tamed. But the low grip problem in braking and cornering is still there. When it slides all the way out of the track at the speed other cars are doing fine, it's nothing like a light weight car with fat tires. Overall a very bad handling. I can't think of any other car like this. Argh~

I love its look and sound, how I wish I can enjoy driving it.
 
LS Chiou
But the low grip problem in braking and cornering is still there. When it slides all the way out of the track at the speed other cars are doing fine, it's nothing like a light weight car with fat tires. Overall a very bad handling. I can't think of any other car like this. Argh~
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Other 1960's cars, or are you trying to corner it the same as modern cars? Are you using 0 camber?

This has given me a good enough reason to give it a run around the ring tonight. Will post my thoughts...
 
OK, I've not tried those old muscle cars, yet. Don't know how they drive in GT6. In my memory of GT5, they were not as slippery, though. I'll give them a try to compare.
 
Shelby Cobra - oil change, supercharger, add/shift ballast to 550pp 50/50 weight distribution. BB 6/5, LSD 10/50/10. Added adjustable suspension, but didn't adjust the settings.

7.40 around the ring with stock tires. No aids except ABS 1, grip set to real. Only did 2 laps (first was red). Can see another 10 -15 seconds with more tuning and getting used to the car.

Smooth and gentle inputs, shift early to keep revs down. Brake early, gently. Slight throttle ( 20%ish) while cornering.
 
In GT5 with the tire load indicator (that isn't in GT6) you can see that this car's suspensions bottom out all the time, so perhaps that's where the problem lies. Try increasing suspension height and stiffening them a bit.
 
Cobras aren't exactly the last word in aerodynamics. Outside of that, the rest of the car is pretty wonky in comparison to other fast cars.

Also, consider it's nearly 50 years old now.
 
I've never seen so much sawing at the wheel before the local Cobra club came to the track and went past my corner station.
 
I'm by no means a car expert, but isn't the typical view of classic American car's fast in a straight line, but terrible in the corners? Maybe this car is a little hard to control because of a really old style suspension and a lack of Aerodynamics?
 
Ryanswannell
I'm by no means a car expert, but isn't the typical view of classic American car's fast in a straight line, but terrible in the corners? Maybe this car is a little hard to control because of a really old style suspension and a lack of Aerodynamics?
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Ahh but it's not an American car. The Chassis and basic body structure are from the AC Ace which is British. British cars usually handle well but are low powered.

The Cobra in the right hands is a very fast machine, but it's tricky to get right cos of the sheer torque and power in such a small lightweight car.
 
Ryanswannell
I'm by no means a car expert, but isn't the typical view of classic American car's fast in a straight line, but terrible in the corners? Maybe this car is a little hard to control because of a really old style suspension and a lack of Aerodynamics?
Click to expand...

In real life, the big-block Cobras were not great track cars. Too much weight over the front tires, and not enough grip to properly put the power to the ground. Now the small-block cars, FIA 289 Cobras were great track cars and they were somewhat successful. Shame we can't get those instead of the the big-block cars.
 
I've driven a kit car built to original specs aside from an even more so oversized engine. One of the worse cars I've ever driven, and I've piloted some royal turds. Even throttle in a straight line makes this car want to breakdance like its 1988. So, its actually pretty acurate to me. I'm sure what I drove couldn't be any more poorly set up than how PD imagined it. it is a fun car. its homicidal and I appreciate that, though I wouldn't call it competitive unless you're up against a Frenchman on rollerskates.
 
I read an article a while back in an old number of Road and Track about the Cobra. It said that only a handful of race drivers dared to take the car to it's limits. I'm no expert, but I imagine the car drives how it should. The first thing that comes to my mind is that the car has too much power for the nimble chassis and if you add the short wheelbase, that might be a reason why the car is so lively.
 
I love to tune the 66 cobra to the 450 pp class. I use 50/50 weight, sport hard tires and an LSD setting of 12/14/16. I wanna say power wise is 265 hp 370 Lbs-ft (emulates more of a small block power level). You can spray it for the straights and be very competitive in classes above the 450 pp.
 
Newland
I've driven a kit car built to original specs aside from an even more so oversized engine. One of the worse cars I've ever driven, and I've piloted some royal turds. Even throttle in a straight line makes this car want to breakdance like its 1988. So, its actually pretty acurate to me. I'm sure what I drove couldn't be any more poorly set up than how PD imagined it. it is a fun car. its homicidal and I appreciate that, though I wouldn't call it competitive unless you're up against a Frenchman on rollerskates.
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hahaha, this actually made me laugh out loud forreal.
 
I belive that if you soften the rear it will have more traction, also go for way lower damper compression (1-3)than extension (6+)is a good way to retain grip and stiff (4-7) front roll bar.
 
Johnnypenso
Best guess is PD is simulating the old school tires and suspension of the era.
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They are and this SOOOO bugs me. Just fit the car with comfort tires stock to simulate the experience of bias ply tires, don't mess up the whole car.
 
Voodoovaj
They are and this SOOOO bugs me. Just fit the car with comfort tires stock to simulate the experience of bias ply tires, don't mess up the whole car.
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Even with modern tires the 427 Cobra has a reputation as an uncontrollable beast when you start getting near its limit.

It has a 90-inch wheelbase. That's a full foot shorter than the current Honda Civic's wheelbase and nearly 10 inches shorter than the wheelbase of the current Honda Fit. Any car with that short of a wheelbase and as much power as the 427 Cobra had is going to be more than a handful in corners.

I think that there are a lot of people who just plain don't understand how much a long wheelbase contributes to stability through corners.

Even with modern tires the 427 Cobra is a very difficult car to drive near its limit so I don't think this is a case of PD trying to simulate bias-ply tires. Besides, every racer I've spoken with who has used both radial and bias-ply racing tires has said that the bias-ply tires give more warning before losing grip and are easier to catch when they do lose grip (though radials have higher total grip). If PD were truly using the car's inherent modeling to simulate bias-ply tires, it would be easier to tell when you were getting close to the limit and easier to catch the car before it stepped out of line.
 
Irl you get feedback through all your body, driving a tough car only using visual and crappy audio cues is way more dificult. Maybe using a softer(sportier) compound at the rear may help tame it a bit.
Also longer wheelbase is better for high speed stuff, this is why the rear wheel steering in the new porsche gt3/turbo tries to emulate longer wheelbase from a certain speed on and a shorter on the slower corners.
 
Thanks everyone for the inputs:)

@ shirakawaa, Great info ! I didn't know it's bottoming out. During my tuning, I just vaguely feel it shouldn't be set too low because I see the fat tires are already scrubbing the fenders. I'll look more into it.

@ JMR450, I also thought it should be heavy in the front and light at rear. But funny, in PD's simulation, it's front/rear distribution is rearward bias! (just like Ferrari 599 and Lexus LFA !)

@ Zenmervolt, Great info ! I didn't know the wheelbase is that short. Do we have this spec in the garage page? (The text size on the screen is just too damn small, I'm struggling in reading them all the time. I must have missed a lot of things.)

Last night I dug out several old muscle cars for comparison: Shelby GT350, Buick Special '62, Pontiac Tempest Le Mans GTO '64 & Firebird Trans Am '78, Dodge Charger Super Bee 426 '71, Chevrolet Corvette C1 '54 / C2 '63 & Camaro SS '69.

Right out of the box, they are not perfect, of course. But overall easy to predict and deal with, smooth reactions near their limits. Similar to my impressions on them in GT5 (excluding Firebird, it's not there then). They are mostly heavier and less powerful than Cobra. Among them, GT350 is somewhat snappy at some situations, but not hard to catch. While the C1 is so slow and dumb. It keeps pushing wide. (I haven't tuned it like I did in GT4&5. I remember it's well-balanced and very capable after being tuned.)

And yes, their grip is bad, too. They don't do quick lap time. Maybe, I must admit my expectation on Cobra is just too high.

I treat it as a tricky MR/RR and have been working on the tuning for quite a while. Here is what I have now:

Shelby Cobra 427 '66, 570pp (663ps), 1138kg (f/r distribution= 46:54)

SM tire (I need more grip)

Ride height: 100 / 100
Spring: 10.7 / 8.2
Damper: 8 / 5 (for both ways)
ARB: 3 / 2
Camber: -0.3 / 0.0
Toe: -0.04 / 0.28
BB: 6 / 5

Fixed 5 speed transmission (top 270km/h, so not ideal for high speed track)

LSD: 22 / 6 / 30

70kg ballast at the position of 40% (rearward, but not to the extreme)

Compared to stock, it's easier to drive, smoother acceleration and more stable. The most important is less snap oversteer. But overall it's still not up to the ideal condition as I like. I came to the bottleneck. Maybe it's the unbeatable short wheelbase.

Try the tuning above if you like, and tell me what you think.

Thanks in advance :)
 
Professional drivers at the time were pretty much sliding every corner to rotate the chassis. It's not supposed to be an easy car. And it's not known to be an easy car. It's light chassis with a big motor with big power.

I think they did it well, to be honest.
 

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