TB993tt

Vmax is a gathering of maniacs in mid England attempting to max out their cars down a runway with the maximum speed being measured after approx 2.2Km/1.4miles with a rolling start.

The fastest of the day was Leon S with his freshly regeared, 102 octane fuelled, 560hp Ruf 993 – his amazingly large cahoonas took him to 198mph.

This sort of speed in a 993 is not for the faint hearted, I found it a quite traumatic but necessary thing to do.
Leon reported good stability with his deep Ruf nose (possibly a relative term ) but I know MOD’s beast was like mine ie “lively” – here is a clip from the AX22 recording lateral Gs, check out the “movement” at ~170mph.

I approached this event on the basis that there is a good standing start straight (before you go round the corner onto the main runway) where I hoped to line up and do some good side by side runs up to 145mph.

I ran against Leon, we were pretty much side by side with maybe him gaining 1 car length as we neared 140mph – I have that on video.

I ran against a georgeous CGT and we were dead even up to 145mph at which point the CGT carried on around the corner and I bottled out on the brakes –I have this on video.

I ran against a Yellow Ruf GT2 (Nardo I think) I gained maybe 3 car lengths by the end at 140mph – No video

As far as the top speed, my car is geared (running the BBS race wheels) at 28.3mph/1000rpm in top so at peak power, 6500rpm it was going to do 184mph, so I wasn’t expecting silly speeds. As it turned out, the car sat around the 7000rpm mark (on the rev counter) and managed 193mph.

Back to the acceleration. I was disappointed as previous analysis showed that I should have put a few lengths over the CGT (the only known quantity) up to 140mph.

When I got home I got stuck into the AX22 data – something was amiss !
The CEL light had been coming on and off for about a week before and has been on consistently for the last 24 hours. I had noticed that the boost gauge was not reaching the levels it was before, but put it down to the atmospheric conditions of the day (and my butt dyno still felt good Gs). Not so

Being the consumate anorak I have done many acceleration runs with the car in its latest spec so have a good reliable average of where the 60-130mph should fall.
When I compared it to the run on the airstrip it was over a second slower !

I jumped in the car, took it to my (private) road and did a 60-130mph to compare with the same road runs I have on file. There it was – 1.2s slower 60-130mph !
I have overlaid a run with the engine running right compared with the airfield strip:

The beauty about the AX22 is you can see what the graphs mean in terms of how far ahead/behind the car would be in comparable runs:
First you overlay two runs and record the maximum speed attained in a given time period – here it is from 60mph for 13.5 seconds.
The engine running right attains 158.5mph and with CEL 152.4mph

Next you switch the AX22 analysis to distance and mark up the distance travelled at the respective speeds: Engine right 726 mteres, CEL 704 metres – so this tells me that the CEL is putting the car 22 metres/72 feet behind where it would be if all was well 13.5s after 60mph at WOT !

So there are my excuses for not ripping past all and sundry on the acceleration straight – as for the vmax, that is for brave people, I’ll probably stay rev limited
Just a footnote to thank the organisers, Craig and crew - great job and as safe as 190+mph can be

kennyboy

I need to get to a vmax meeting, it sounds like petrol heaven!

Jean

Thanks for the update TB

This is a great result nevertheless, especially since you have hit the rev limiter before the end of the run, so a taller 6th would have probably given you a few more miles.

You must have had a very serious scare at 170mph with those almost 0.3G of lateral movement. That is A HUGE sideways shift, and I really wonder how you kept your foot to the floor.

The difference between the two runs is very big, it looks like more than 1 second difference on a 60-130mph. You seem to have something like 50HP less than usual.

It is good to see so many 993s at the top!

bb993tt

I've seen this event on the PH forum, but never knew what it was. I'm probably being *very* stupid for asking, but when's the next one?

Jussi

Can you put those videos to someplace where they can be downloaded?
I like to see those videos! All Porsche stuffs are welcome
Do these Vmax days have official web pages?

clubsport1

Toby, nice to meet you yesterday, very nice car....loved the doors

Official Vmax site is here, http://www.vmax15000bhp.com/

Woodster

Excuses, Excuses...

Just kidding Toby, wish LAT and I could have been there!
Next Spring/Summer perhaps. That Leon's car must really
boogie!, I would love to see America's greatest over there
against the Europeanos. I had my old 993TT up to 175 indicated
(not actual) and they are a fair handful--the 996TT on the other hand
just slips through the wind almost unoticed.

You guys do it right!!

Thanks for sharing and get us some videos.

did you say your were able to extrapolait what your zero to V-max was?
maybe not because you must go around a bend and then let er fly?

Kevin

Toby, nice to see that you made it without any damage to your car.. Like Jean said, you throttled thru it..

Now you can spill the beans on your engine build (smile)..

TB993tt

Nice to meet you too, a fellow minimalist

Woodster, you can just about make it out on the top graph - the 0-300kph (186mph) [allowing for a 3.7s 0-60mph] would be 30.3s . 186mph comes up right around peak power so I guess the car is geared right for this sprint. I would expect it to run it somewhere below 27seconds when working right, although the aerodynamics are a bit unknown and I think my fat *** was working against it at the very top.
0-193mph would be around the 36s mark, but after 186mph we are falling out of the real power band.
Kevin
Engine build may not be over yet, the CEL is probably not the problem. I am told it is more likely to be one of the turbos which is not pulling its weight and the other one having to overcompensate to hit the target boost numbers, presumably resulting in a combination of hotter boosted air from the overworked compressor and not being able to hit the boost targets through lack of compressor output (of the good one) - this would tally with the lower boost numbers which I saw prior to the airstrip (I wasn't watching the boost gauge on the runway funnily enough )

Stummel

damn TB, that is too bad. But nevertheless a good result. Have you checked the CEL codes?

It would be a pleasure for me to drive your car to the limit on the next V-Max 8-)

TB993tt

Stefan
I may very well take you up on that

Stummel

hell, I would even pay the fuel :-)

TB993tt

Don't speak too soon, I will visit the garage Leon did for some 102 - it costs 3.50Euro per litre

leonsamonas

thanks for your kind words toby, please send me a copy of our run, i would be very grateful . p.s do you also have our 2nd gear rolling run on the long straight, i noticed that particular duel was omitted

FYI the 198mph run was my first of the day (with a full tank of fuel) then on i was persuaded into racing others on the long straight and a powersliding sideways action on the following sweeping turns, shame because had i stayed until the end of the day and obsessed (when everyone else achieved their best speeds with little fuel) i could have perhaps squeezed that magic double tonne in 1.4 miles oh and yes it was pulling left and right like a m*&^%cker at 198 (201 indicated BTW)

It was good to meet you bro., until next time...

Stummel

I gladly pay for that if we do like 10 runs on that day.

The perfect opportunity to film your car from the outside

PM me the infos for the next V-Max