kusee pee

Mike, I can read posts like this all day long I must admit, whenever I leave work and see the 965 in the car park it makes me grin all over - what a car it is!

graeme36s

The reality is that we drive cars that were not built for profit alone. In the era that our cars were built Porsche very nearly went broke. The recession in the UK etc. When you shut the door our cars feel that they are hewn from granite. I have never driven the 997 but I have raced the 996 supercup car, incredibly competent but does not quite do it for me. The 996 GT3RS is a little different and is an awesome piece of kit, but the maintenace costs are astronomical. I was at Silverstone a couple of years back and the guy that owned the Daytona car that I raced was trying to talk me into buying it. A couple of close friends were with me and offered to chip in some money. I told them to shut up and walk away. As I explained later, so I do a deal for say £30,000. If we pop an angine which is very likely thats £56,000 excluding v.a.t.. They thanked me afterwards. Buying the car is the cheapest part. With the old school Porsche's this would not be n issue.

911addict

Cobalt said: "Actually the 964 3.6T is only rated at 0-100mph in 9.5 seconds so yes they are faster out of the box. But that is not bad considering the 3.6T is rated at 360hp vs the serious Hp numbers rated fro the 997GT3 and 997TT. I had used my GTimer to test my turbo and I had recorded 0-100 mph times in my turbo as low as 9.0 seconds with a botched start and a 0-20 time of 2.1 seconds. I am sure if I could get the car to hook up I can see 0-100 times of 8.7 seconds or quicker."£

And other anecdotal evidence from hemi and others, how is it that our 965's are SO DAMN FAST?
Our HP numbers are way behind modern supercars. Is it our torque? I thought again that GT3/turbo997, etc. and other marques too, are also higher on torque...or are they?

And its not weight, we're all quite similar...

kusee pee

I'm with you addict - I don't quite get it (even though it makes me smile to think that our beasts can eat up much more modern machines).

tjr

I agee with you both. The 3.3 Turbos, according to Autocar, were rated at 0-60 in 4.9 seconds and 0-100 in 11.4 seconds. Obviously the 3.6 has more power and torque but I can't see how that would knock nearly 2 seconds off the 0-100 time. Having said that, I've noticed that US publications seem to run much faster acceleration times on 911s than in Europe - perhaps it is the gearing or just that American horses are much bigger than European ones!

Anthony's car has got 420bhp IIRC so that may be why his is so damn fast...

cobalt

A lot has to do with power to weight and drive train loss. The 993TT and 996TT are all wheel drive. There is around 20% drive train loss on these cars vs 15% for our 2 wheel drive systems. So for a 408 hp car it has around 326 hp to the wheels vs our 360 hp cars that put down 306 hp or so. The all wheel drive system also ads weigh to the car. So this ads to the equation. When you add it up we should be quite close.

It is very easy to bump up the power on our cars and you can see 365 to the ground easily. The TT's will always have an edge off the line because the all wheel drive system can launch the car better from a stop. Although our cars are sluggish off the line the power can come on abruptly and this surge also works to catapult the car forward, unlike the TT's which have a very linear power band in comparison.

The numbers I have from the GTimer were when the car was new and I was just running B&B headers and nothing else. IIRC the Hp was at 370 bhp. So just 10 more than stock. Since then I have done some minor changes and she runs around 365 to the wheels. I would love to get her to 400 to the wheels which is more than fast enough for street use.

SA Mike

Anthony what changes have you done to get where you're at right now.

cobalt

Very simple work easily reversible and safe. On top of the B&B headers I added a HFK27 turbo, 1 bar spring, Billet diverted valve, drilled air box K&N filter and swans neck in place of the muffler. Still running cat. The most effective improvement was having an excellent turbo tuner, tune the car on a dyno. The car is running slightly rich to play it safe. He feels he can extract more HP if I want to but I find the car to be nearly perfect as it is. Maybe not the fastest car but a blast to drive and sounds great.

Staffan

Anthony how did he tune the car?!
Thought you where running CIS?

cobalt

It is nothing like maping an ECU but by using the dyno we were able to optimize the AFR and Rick found an additional 32 hp. The previous shop did it by attaching a meter and driving around, it is actually the way the factory manuals suggests but not very accurate. When we put the car on the dyno it was running way to rich and the dyno run showed 333.6 hp to the wheels when he was done adjusting the AFR the chart showed 364.8 He feels it should read a little more but I prefer to run a little rich vs lean.

hemikuwait

If some one ad told me that i'd be in the same neck of the woods as a gt3 and r34 prior to owning the 3.6t, i would not have believed them....no way. Its a shocking and scary car...the way it just lunges forward in first....ridiculous

cobalt

What car are you talking about? The best part of the 3.6T is how the power comes on. The one thing I found disapointing in the GT3 was how long it took for the power to come on. The Gt3's are too linear for my taste.

Staffan

But how did they adjust the AFR, can you adjust the control pressure on your WUR?

The only thing I can adjust on my car is idle AFR with the co adjuster on the fuel head.
On my car it doesn't make any difference at full boost, logged it several times with a wideband o2 sensor to my pc and there is no difference.
When the car goes full throttle I believe it goes into dumb mode, pays no attention to whatever the o2 sensor says or in what position the co adjuster is in.

I also looked how the co adjuster affects the arm from the "air flap" and to my understanding it can't have any effect on the AFR except at idle and (again to my understanding) it wasn't designed to affect the AFR exept at idle.

If you disconnect the o2 sensor my understanding is that the system goes into dumb mode alltogether, but again no difference at full throttle, at least not what I can tell.

cobalt

Unfortunately, This was a few years back and I don't recall exactly what was done. He did adjust the air flap and the AFR at idle to maximize AFR's at WOT. The curve itself does not change because its CIS but the ratios move up or down the chart. By adjusting the curve for optimum ratios at WOT the power adjusted accordingly. Running too rich starved the engine of its potential max HP. Many shops just set the AFR at idle and leave it. If you make adjustments to your WUR it has shown to adjust the AFR curve, this will help gain more power. At the Hp level I am at we are not approaching numbers of major concern so long as the engine is running properly at WOT the car should be safe.

Sorry I have nothing tangible to help you with. I don't know if this helps but here are some charts of a 91 turbo with some minor mods using CIS and the Brian Leask adjustable WUR. He just installed it and is still tuning the car.

Staffan

Thanks Anthony!
I'm running a bit leaner than I would like when my car overboost (on 2nd and 3rd gear) so I am looking for ways to deal with it. Oh well,I guess there are no short-cuts to be made with CIS perhaps I will make my WUR adjustable or go EFI.
Still, impressive numbers we get from our engines with a "stone age" fuel injection.