Bill S.

Think you have turbo lag?... Try 5 to 60 mph from a roll! That's easy. Car and Driver magazine has been doing it for years. Here's a few fast cars:

5 to 60 mph:

Saleen S7: 3.5 sec
CGT: 3.7 sec
F599: 3.7 sec
SLR: 3.8 sec
F430: 4.0 sec
Gallardo Super: 4.1 sec
CLK63 BS: 4.3 sec
Z06: 4.3 sec
997TT (auto): 4.4 sec
F50: 4.6 sec
996 GT2: 4.8 sec
997 GT3 RS: 4.8 sec

I can get 4.3 sec in my Ruf Turbo R (peaking 1 G!)... How about you?

TB993tt

I agree. Bill, doesn't this render the test more a measure of the grip available ?

Bill S.

Yes, grip would mess up this test for analysis purposes, and the 80-120 km/h test would eliminate that. However, I'd be surprised if there's traction problems with these 4WD cars on a good surface with a rolling start. I haven't heard that being a problem, especially with the new traction control systems.

I mainly started this thread hoping to gather this data because it's an important performance measure in the US. That is, people really like to know 0-60, but given the number of variables on that, 5-60 is starting to become popular as the new "practical" 0-60.

TB993tt

OK Bill, in the interest of data -my drive train didn't enjoy it. Boot WOT at 2mph as the clutch is released, a fraction of a second's lag followed by eruption in 1st gear, ****** second and another eruption..... I carried on to 100 whilst doing it
(Yes it was slightly downhill and 14DegC)
Edit: 5-60 took ~29metres, my schoolboy maths calculates average G between 5 and 60 as 0.72G for my run and 0.58G for Bill's (including gearchanges)

Bill S.

Very impressive!!! 3.5 seconds 5-60 mph! That's a record!

What's interesting is how much stronger your Gs are at low RPM. That's primarily due to your larger displacement and higher compression. I just didn't imagine it would be so much higher.

What's also very interesting is major boost comes on around 20 mph for both of us. That sort of makes sense with the same turbo technology. It's just that your entire curve is raised up due to the larger engine.

Now, what would happen if you had the new 997 turbo technology? Maybe low 3 seconds in a 5-60 mph run! That would be outstanding!

TB993tt

Jussi's was faster than this -"was" may be the operative word, he's been AWOL for a while, hope he hasn't lunched the engine already

Felix

TB993tt

Just "rattling his cage"

Salespunk

5-60 should be done with first fully engaged to get a comparable number. Dumping the clutch will skew the numbers vs. those on the list. The idea behind this test is to eliminate the difficulty of the launch.

TB993tt

Bill, I think there's quite a bit more to it than the ~150cc displacement and CR -If we could persuade other RL 3.8 guys to run some numbers ANY NUMBERS then it would certainly help develop the picture...............However they seem more fixated with "Andial 3.8" identity plaques

Jean

Any performance test is very interesting

IMO this test does not have anything to do with lag, it has more to do with performance, but MAINLY grip!

The 993TT in 1st gear, even in stock form, will accelerate MUCH stronger than the traction than any tires can put on the ground. Best street tires would have around 0.9G to 1 G of grip, a slick maybe up to (a very stretched) 1.2-1.3G.

The chart below shows how many Gs a stock 993TT "could" put in 1st gear, if it did not loose traction. Anything above that line is traction loss, so your long Gs will bounce on and off that imaginary traction threshold line, hitting 0.9-1G, then loosing traction and dropping again, then back up etc... The torque from which this data is derived belongs to my stock 993TT and is real life data, not based on dyno charts.



When you compare your datalogs to this, you will see that you average is probably around 0.7-0.8G in 1st, that corresponds to a 300HP car "if" it did not have traction loss.

In 1st gear , the difference in times is directly related to grip, not much to do with the difference in torque between these two cars, since anyway, they are both beyond grip threshold throughout 1st gear redline.

A test done by a magazine on several 993TTs and Gt2s showed that camber had a big impact on acceleration times from 0-60mph as a result of not having the full tire width flat on the ground upon acceleration. This was the car that was used.




Check out how slicks have better long Gs in 1st gear. It is the same car doing a quartermile run (not on dragstrip).

Street Tires



Slicks



This is also the reason why your times and speed on a dragstrip will be substantially higher than the street, as a result of grip.

Basically, any of the items below can make the difference between Bill S. times and TB993TT, sorry to disagree, but it has very little to do with lag or displacement!

Any of the items below (and many more) will make more difference in this test than difference in power between two 993s:

-Camber
-Tire width (285 vs 295?)
-Stiff vs soft suspension (huge impact)
-Tire condition
-Road conditions
-Road temperature
-Weight
-And....Power (end of first gear mainly, and in second gear certainly more)

Finally (and sorry for the long post) here is some data from my stock 993TT for kicks. This was not meant to be a 5-60mph best run, I happen to have this data on my hard disk, it was taken last summer (100F or so maybe) , tires were badly worn out. 5-60mph in 4seconds, no clutch action, just smashing the throttle. Notice that grip stays at stable 0.8Gs, the maximum of this tires.

Average long Gs 0.67G..
Distance to cover 5-60mph: 59meters. (TB..29meters?)...
In first gear, 5-30mph: 1.5s. Bill. 2.2 seconds, TB993TT about 1.6seconds.
The above is proof that traction is everything in these runs, definitely in first gear.

ScottMellor

Toby, two things and I say this with all love:
1. You have waaaay too much time on your hands.
2. "Bite Me!!"

LAT

Jean Buddy, nice rear bi-plane wing....

Bill S.

Jean,

Thanks so much for sharing that data! Of course, I completely agree with you, as always. Two reasons I started this thread:

1. When we collect enough data, we can overlay the longitudinal Gs for several cars up to the traction limit (1G or so). That will clearly show the difference in lag between the cars, as well as the off-boost performance at low rpm.
2. It's fun to see what 5-60 these cars are capable of, and how superior 4WD and a rear-engine configuration is in this type of test on street tires.

And, I agree with TB993tt... let's see some Andial results!

Jean

Bill,

Of course, that's the fun part, let's get data
I hope we will! At least on a 5-60mph they have a chance to be competitive, with some fat tires