performance mods

[Guest]

Know what you mean, Mike.

I, too, did what I did "simply because I fancy it" as you say.

Funny thing about enthusiasts' world, be it running a Porsche / playing a sport / whatever it may be- the 'experts' are experts because they've had more experience than us.

They may have had different experiences, though, in that what works for one guy may not for another. eg - the subjective 'feel' of a modded braking system will be different to you / me and two 'experts'. The laws of physics, however, remain immutable.

Sports analogy: If you're in the finals, you're already a champ. The contest is merely to compmare shades of excellence.

Porsches: A 911's factory brakes are already very good indeed (if working properly)

 

[Guest]

The problems I had with standard brakes when I first got the car? Too spongey, lots of fading, lots of pedal travel, ineffectual.
They weren't exactly confidence-inspiring. So I asked around various independents.
Some said: '911 brakes aren't that great, so don't expect too much' yet others said: 'What you talking about? - it's got the Turbo's discs and should therefore stop on a pin.'
I just think mine weren't running right because they simply hadn't been used (or used really hard).

Can I assume that you have a Supersport with Turbo brakes? If so, you already have bigger brakes than the Monoblock (ie Boxster brakes) package that 9M are selling. The Turbo brakes are the upgrade that most of us with little brakes aspire to have. With Turbo brakes you get massive 32mm thick discs (Boxster brakes are 24mm discs just like the Carrera - hence they bolt on) and 4-pot calipers and you gain huge heat sink capacity.

The standard Carrera brakes should be more than adequate for road use. The disc and caliper size are more than adequate for a car of the 3.2's weight for road use - just take a look at the brakes on contemporary cars. The 3.2 brakes are basically the same size as the Boxster brakes. Porsches are known for having the best brakes full stop. This is not just a recent label associated with the "Big Reds" but has been the case for decades. The 70s and 80s brakes are no longer state of the art BUT they are still comparable or better than many brakes fitted to 2004 sports cars.

For track use the 3.2 brakes work well (not great) but can have a couple of critical problems. First, it is difficult to get everything to work as new. Our cars are now kind of old. I have replaced virtually everything with new components (calipers, brake lines, discs, pads, master cylinder) and it is still not perfect. We also found a vacuum leak that was causing the booster to work incorrectly and give a soft pedal. Worn discs and pads can also cause a soft pedal. The system is also difficult to bleed correctly. The proportioning valve is known to trap air. Secondly, particularly when using R-compound tyres, the heat sink capacity is marginal, hence, after 5 or so laps you get overheating and boiling fluid. This can be mitigated against with high temp (and fresh) racing fluid and racing pads and lots of cool air ducted to the centre of the disc. I survive even 45 minutes of hard track time without fade BUT I have to have fresh fluid (and often pads) after every couple of track days and my pedal is never the firmest nor can I brake the latest.

The Boxster calipers do not really remedy either of these problems. However, they do give you a bigger, stiffer (and lighter) caliper that takes bigger pads. They are probably a little better at dissipating heat but the primary heat sink is the disc. They are not a pointless upgrade but neither are they the ultimate solution - which is a pity as the cost and bolt-on compatibility make them superficially attractive. Nonetheless, I have come very close to buying them []

I seem to have strayed off track a bit - perhaps you can be more specific about the brakes you have and the problems you have - assuming you want some advice of course.

Richard

 

[Guest]

Hi Richard

Yes, I have the Supersport with Turbo brakes. Re: the "problems", I've concluded that I'm perhaps just being too fussy. They don't feel awful anymore, just not, well, modern (like, say a 993's for example). They did, however, feel awful when I first got the car and before any servicing work had been done to it.

Richard, I really must thank you for your considered opinion on this issue in your last post. You haven't strayed off the point at all. Your comments have saved me an unnecessary £1500+. You mention that worn components give a poor feel, but as these have been replaced now, what I'll do is give it some on the street, then get used to driving on the track, THEN re-consider upgrading (if at all necessary at that stage).)

Maybe I'm just scared to stamp on the pedal (no ABS). In any case, it seems that the only way to find out would be to take tha car onto the track in a couple of months' time.

Which one is the most first-timer friendly in your opinion? I need tuition, too.

Regards

 

[Guest]

The most often recommended track day for "beginners" is Bedford Autodrome, primarily because there is nothing to hit, however, after thinking about this for a bit, I have come up with a slightly different take on this. It *IS* a good learners - track because it has lots of run off areas - but it can be rather hard on cars. Should be ok for cars with turbo brakes [] but for others it is tough. The reason is that it has a lot of short straights followed by sharpish corners so there is a lot of hard braking and not much opportunity for cooling. So I would say that it is virtually compulsory for std 3.2s to get at least high temp fluid and new (preferably track oriented) pads if you want to have a good day.

The other downside to Bedford is that it is in August so its a long time to wait.

Castle Combe is usually early in the season but you have to book very quickly because being close to London and having ludicrous noise limits meaning only 7 cars on track at once it sells out very quickly. I also think its both intimidating and boring. I rate the end of the "straight" as one of the scarier bits of track in the country. Because it is so damn bumpy just where you want to brake. I quickly reached the point where I felt that I had reached the point where pushing any harder exponentially increased the risk. So I got bored. Call me soft but its just a track day and I like to drive my shed home in one piece.

I like Pembrey in Wales. Its a small track and is easy to learn. IMHO, it only has one potentially dangerous corner - but that is easily dealt with by slow-in fast-out. It has a nice mix of corners and flows well. Gets my vote as a good beginners track.

Oulton Park is huge fun but could be dangerous in the wet as there isn't much run off in a couple of places. It has some wonderful elevation changes and it is a lot of fun. One to mark down as a must do but be a little careful.

I love Silverstone - not sure why but it has some great corners and is very safe as it has all the runoff areas for the GP. It is a pretty quick track but it flows nicely. After Rubens "drive of the decade" in the 03 GP how could you not like it? Even after a dreadful wet 03 trackday with multiple aquaplaning spins I still love it. It is expensive however.

Goodwood, I want to like because of the history and the atmosphere, but my head tells me that this is just about the most dangerous track I have been to. It is very fast and has too little run-off and too many solid banks to hit.

I haven't been to Brands as I feel the evening track days are a bit of a waste of time.

So, having said all that, the bottom line is that any track day is as safe or dangerous as you make it. Ultimate control rests in the driver's hands. In all the track days I have been to I would say that the vast, vast majority of first timers are far too nervous and cautious to actually have an accident. Occasionally, there will be someone with too much bravado and too little ability - these guys normally have brand new 996s not 3.2s. The car, for them, is all a part of showing off not true enthusiasm. If you can check your ego at the gate then you do not run this risk. If you trust yourself to drive fast on a winding B road then you can trust yourself to drive on a track. People who say "I don't do track days because I would crash" truly scare me. What are they like on the public road? Do they think that all self control goes out the window as soon as they hit the track?

The key point if you want to be safe, IMHO, is to leave every competitive inclination behind. Then you have nothing to prove. You drive only for your own enjoyment and development. This is the zen of track days [] Of course, I am far too competitive and sometimes push things a little too much, but then I have been doing this for a while []

HTH

Richard

 

[Guest]

Sounds like fun. You realise you've hooked me deeper, haven't you?
Now I'm gonna start investigating each one.
I'll keep ya posted!

(Don't worry about ego on the track. I have none. No shame either, according to my wife!)

 

[Guest]

There is an other way to get more torque, change the inside 2th 3th and 4th gear of your gearbox ( 915 or G50 ) this will work!! and don't have to do anything on your powerplant.

It is much cheaper than placing an 993 engine, and it will outrun it easely

This is a good point. Very good performance gains can be made by this method, however, I would like to see the std 3.2 with short gears that can outrun a 3.6 Varioram engined 3.2 - I think this may be asking a little much.

Richard

 

[Guest]

Martyn - the white "PORSCHE" logos ar available from Porscheshop - listed as Brake Caliper Decals P/set £17.63 incl VAT + £2.50 p&p.

Steve
87 3.2 Carrera - C2 bodykit

 

[Guest]

Will these fit the 3.2 carrera, or are these for the latter models?
Thanks
Martyn

 

[ClubSport 911]

Regarding the issue of changing gears to improve performance, this is well known and also, (thanks to a CS owner Brian Hunt) well documented as a "good thing" for the Carerra 3.2

Brian had his car very subtly re-mapped (i.e not too agressive, and with more to go) and got 247hp. He then lightnened it further (spare wheel and rear wooden cover out ) and then changed some of the gear ratio's on his G50 box.

He and his CS were well known in the hill climbing circuit, and as per recent suggestion from Walter in NL, can produce some outstanding and "out of class" results"....but I will not speak for him - here's his views:-

"2) Lower 3rd , 4th and 5th gears from( Power Haus in USA) these reduce the
gearing in those 3 gears by about 8%, so when you change up at say 6,700 the
next gear comes in at about 5,300 right in the power band, instead of 4,4,200.
From the power chart of my car on its dyno run, it produces 167 BHP at 4,400
and 230 BHP at 5,400. So you can see that at the change point it is
equivalent to having another 63BHP available. Or put another way you can keep the
engine at a position where it is always giving between 230 and 247 BHP, rather
than 167 and 247 BHP. see comments below.

The above 2 items were fitted to the car only 1,000 road miles ago, and have
only done one competition event, and boy they really work. At timing point
shortly after the start I recorded 67mph against 70 mph for a 330bhp 993 RS
6-speed lightweight weighing only 1146kg

So, don't be junking that 3.2 just yet....get the weight out, upgrade the DME and change the ratio's for quite amazing performance.

Rgds

STEVE

PS - I have a lot more information (charts etc) if anyone is interested.

 

[Guest]

I am a million miles away from having a clue regarding gear ratios etc.. but I thought it was torque that was the important think when it came to acceleration therefore the gear ratios should be optimised to stick you in the appropriate position in the torque curve when you change not hp curve.

A standard 3.2 produces max torque at 4800rpm according to my handbook.

I guess you can't argue with experience though.

Any thoughts.

Cheers

Andy

 

[Guest]

Andy, well spotted. I was just thinking "but what about torque...?"

So, can we conclude that the ideal gear set would drop you into the next gear at 4800rpm?

Steve, if Brian is only dropping to 5400rpm, then presumably he only has a top speed of about 115-120mph and cruising at 100mph he is doing 5500rpm in 5th [&:] On the other hand you say that the gears are only an 8% drop. Is it just me or does something not quite add up. I am just curious - I basically understand what you are saying []

The idea of short gears intuitively makes a lot of sense. There are various corners at various tracks were I find that second is too low but third is too high. After screaming around for a few laps using second in the tight corners, I often end up reverting to third and just accepting that it takes a couple of seconds for the car to climb into its torque curve and get on with the job.

I found this on the 9M site (I am sure Colin won't mind the free publicity):

Close-ratio street and racing gearsets are available from 930 Motorsport to maximise the performance of the 915 and G50 transmissions. Since closer gear spacing results in faster acceleration, this often overlooked tweek is one of the easiest ways to improve performance without compromising reliability in any way. For street use we recommend replacing the 2nd to 5th ratios with lower slightly staggered gear spacing to reduce the RPM drop whilst going up through the "˜box. By reducing the top speed in 5th to around 150mph, the effect is as good as an extra 30 bhp.

For track use a different strategy is required to produce an "active" gearbox by changing ratios at both ends of the gearset. Raising 1st gear allows more controlled starts and active use in slower track corners, then slot in a taller 2nd gear with stock or special 3rd & short 4th & 5th gears for the complete package. Special input (main) shafts can also be supplied to allow convenient 1st gear ratio changes for different circuits. Gearsets vary in price according to the ratio's required, typically starting at around £1800 fitted for a custom 2nd to 5th set. Please call with your specific requirements.

ciao,

Richard

 

[Guest]

If the car will run out of puff at 120 in 5th then what are the problems in putting a 993 6 speed box in?

 

[Jamie Summers]

Richard,
I was rather hoping that the increased rev limit on the Steve W chip will go some way to solving the running out of puff in 2nd problem - I know it's not a huge increase but it might be enough. Bedford will be a good test of that esp. the left hander before the long straight and the long right hander after the hairpin at the end of the straight. I'm doing a day there on Sat 13th March (anyone interested let me know....) and so we'll see what happens !

Jamie

 

[Guest]

If the car will run out of puff at 120 in 5th then what are the problems in putting a 993 6 speed box in?

Size maybe? Certainly an issue in a 915 equipped car. Lack of hydraulic clutch in 915 car. Also maybe cost, linkages to shift lever, interface between gearbox, clutch and flywheel. Would also need to know the ratios. to establish if its any good.

If the reductions Steve mentions are only 8% then you should still be good for an indicated 148mph (or so, based on impromptu top speed testing results[8D]). 9M mention gearing down to 150mph and quote 30bhp as the "increase". 8% sounds about perfect and would mean the revs drop back to 4800rpm rather than 4400rpm for example - right on peak torque []

The only place I am on the limiter at Bedford is in second on the short straight before the 1st gear hairpin. IIRC, I shortshift to 3rd in both the spots Jamie mentions (certainly in the first one) as they are gearchanges in the corners and the shortshift limits the "push" allowing me to keep the car in the right position on the track. Sometimes it is quicker to position the car just right for the next 2 or 3 corners than worry about getting maximum speed in the 1st corner. The Becketts/ Maggotts complex at Silverstone is a prime example of this. I take a line like I have seen taken by the FIA GTs, FPAs etc to get me on the gas for the Hangar straight ASAP. The instructors do not teach this line, but the proof is in the pudding. I took a ride in a 996TT on R compounds and he was pulling only 10mph more than me (on road tyres) at the end of the straight.

I've strayed off track again...

RB