Adrian

Dear Howard,
One of the problems with forums such as this is the generalisations based on local knowledge only that are applied to every conversation.
Please do not believe all that you read until you have checked things out for yourself.
The top of the line Porsche tuners I have visited (notice I say I have visited) are not garages, they not are rice makers, they are tuners and manufacturers of car products.
Companies such as Sportec, RUF, Gemballa, TechArt are TÜV approved car parts manufacturers. This means their facilities are licenced. This means their equipment including all their testing devices such as dynos are required to be calibrated and checked at intervals from 2-weeks to 6-months. Even their digital voltmeters have to be calibrated. These facilities are subject to inspection by the TÜV at least once a year. All the parts and upgrade kits etc they wish to sell, have to be homologated to obtain approval, the famous TÜV tag.
There are some extremely sophisticated set ups in these facilities.
A new one I know of installed down in Lausanne took over a year to build and 3-months of testing before they were licenced and approved.
I do not know what they do in the UK or the USA because I have never visited a tuner in these countries yet. I do know what they do in Germany and Switzerland. I would be happy to stand by any data provided by these companies.
There is an invitation for people to visit Sportec in September. Drop by and see their dyno. You will find a highly sophisticated, environmentally controlled set up that provides consistent results based on the requirements and tolerances set by the TÜV. If you cannot visit Sportec try and visit TechArt, Gemballa and RUF.
Ciao,
Adrian
964C4

Kahdmus

Adrian, thanks for the explanation. However if the results are reliable then why not have a before and after measure? I'm still not clear on this. Not that its terribly important, I was just curious as the argument seemed to make sense.

Ultimately, as I said, YOUR impressions after the work is complete will really be the most important yardstick and the one I'd place the most faith in!

Want a C4 to experiment on stateside? LOL!

Cheers,

--H

Christer

The only figures that matter are hp at the wheels. The fwhp is only a calculated value based on what the tuner tells the machine to do. Sportec or any other tuner should be giving you a before and after run as part of the job, this is standard. In fact, IMHO they should dyno any car to make sure the power output is healthy as tuning a tired engine is not a good day out.

There is no extra effort and no (or very small) extra cost. This one is a no-brainer. Really. Its a bit like going to Weightwatchers without weighing yourself first.

Adrian

Dear Howard,
I thought I had answered this question. I am not interested. I do not care what the change in numbers is. I might get 40 HP somebody else might get 30 HP somebody else might get 2 HP. What is important to me is that I get the minimum offered amount of 285 HP.
There is also a practical point. To do a proper dyno run takes time. The car cannot be worked on whilst it is hot. Time wasted and money wasted. I pay for the information I want not what others want.
The numbers game is also extremely misleading and can easily come back to create serious problems.
If you fit a product that claims a 30 HP increase then you need before and after dyno runs to confirm the improvement. No argument from me on that one.
If you have a product offered to provide X amount of HP at the end of the process then it is up to the individual whether they are personally interested in their starting point. I am not. If I get 285 HP or better then I will be happy. I will never claim a difference increase. I will just say I got what I paid for.
Let me tell you that if you provide differences on forums such as this and say I go from 250 to 285 and get 35. Somebody else would expect their claimed 260 to rise 295. When they only get 285 they will be all over this board complaining about how they were ripped off.
My own personal expertise also tells me approximately where my own engine is right now anyway.
Seeing as I got my butt kicked by a 993 C4 on the way home from Le Mans it was confirmed.
A Carrera 4 in the USA will be receiving a stage 2 kit sometime later this year for evaluation purposes.
Ciao,
Adrian
964C4

Phil Raby

Well, that has to be the quote of the day; even thought it's only 8.40am

Phil Raby

Adrian, I guess this is all down to whether or not you can trust the dyno. Personally, I wouldn't because there are simply too many variables involved. But I guess we're all different

Phil Raby

I've found Porsche exhausts to be very efficient. Yes, there are gains to be made if you reduce the sound deadening, but I've yet to see an exhaust change alone produce more than about 8bhp. Having said that, a freer-flowing exhaust combined with other mods can be very effective. Still, I'm always happy to be proved wrong

Cheers

Christer

I got 17 or 18rwhp gain from GHL system. Proved on the same dyno. Thats without any rechip or other mods. Mind you, at this stage of modifications that figure is totally moot.

Adrian

Dear Phil,
Yes this is where we are certainly different
Dear Christer,
You make too many broad and general assumptions based on very little or no personal hands on experience.
Ciao,
Adrian
964C4

DaveK

I guess the main point of a before dyno run is not to see how much difference there is - more to prove that there is an improvement.

I'm curious that Sportec give a final bhp figure rather than an increase - since I can't see how this can be guaranteed. As you say - your engine might be giving 245bhp now - mine might be giving 235bhp. How can the same kit take us both to 285 bhp when we have different starting figures? I can understand that changes to induction / exhaust / timing etc. can give percentage increases - but I don't understand how they can give a definite final figure when the starting point varies?

Christer

Adrian, I must admit I have never visited Weightwatchers (although there is a case for doing so). I am sorry that you had to not only read my naive comments and generalisations, but everyone else's too. I hope that your own personal hands-on dyno experience is of benefit to you in this case.

All the best!

Phil Raby

Re Weightwatchers; you can now do it online - to quote a mate: 'so you don't have to meet lots of fat women'... Could be a useful performance increase - reduce the weight of the driver...

Irishdriver

This reminds me of a CCC magazine article a few years ago. they were taking modified cars to the rolling road.

One Peugeot had many mods (exhaust 10bhp, chip 15 Bhp, air filter 5 bhp, etc.etc.,) but when they put it on the dyno the total power came to less than standard. For some reason the owner refused to have his picture or name in the article and went home!!!

I'm with Adrian on this one. If I pay my hard earned cash for at least 285 BHP then I want to see that I had 285 Bhp.

It doesn't matter where you start from as the tolerance in the production line could mean you have a few more bhp to start with. Hopwever this will be cancelled when you'd fitted the new cylinders, pistons etc. and reprogrammed the lot. In fact even if you had 280 before you should only expect 285 after.

So the only point is if your new 285 is real. Well you can trust the TUV approved dyno or you can get a second post mod test at another TUV approved dyno - but if the result is different (which it will be unless you can guarantee constant temperature, pressure, humidity, etc.,) you'll need to do a third somewhere else to verify which of the first two were nearer the mark .....and when that is different.....

Adrian, go for it and tell us how the car feels as welll as what the dyno says. That will be the real test.

Keep the faith,

David

Adrian

Dear David,
I will certainly be posting all results plus the modification process.
I am really looking forward to it and getting my hands dirty again.
Gail will be with me but she will be test driving the Sportec RS6 whilst she is there.
I also get to play with the 650 HP GT-2 again. This is the auto I will be driving to England for the book signings tour if all goes to plan. The C4 will be the bad weather back up vehicle.
As I also said the C4 will be available in September for checking out by Rennlisters if they want to feel the changes rather thanjust read about them. Good excuse for a trip to Switzerland anyway.
Ciao,
Adrian
964C4

Phil Raby

Adrian

When are you in England? Be good to meet up

Cheers