New to racing, a few regs questions

[midgetman]

Yeah just drive slowly and sensibly. This isn't F1, if you're in the pits you've got a problem and it's not a case of every second counting. Calm down as you hit pit lane, and remember NOT to spin the wheels or lay 11s as you leave the pit! There's a couple of regular contributors on here to attest to that....

[SFurness]

Hi,

As you are going to race at Mallory, which must have the shortest pit lane in the country, you would have to do a racing start out of the pits to exceed the speed limit.

I think they do drop the speed limit to 40kph because the pit lane is so tight but that will be in the SR.

If its your first race just take your time and enjoy the day you can break all the records when you've got a few races under your belt.

Are you doing Mallory as it is your local circuit.

Steve

[Mac944]

When I spectated at Snet there was a speed gun and according to one of the guys associated with the club the marshal using it was pretty strict.

The pit is mandatory so technically the pit is important to the race. I'm under no illusion that I'll be any good or particularly quick given that it's my first race but at the same time I want to avoid as many noob mistakes as I can by being prepared. Not too worried about going in to pits slower than necessary but would prefer to have speedo of some description so it's a no brainer then.

I've chosen Mallory for a several reasons:

1) only past my A.R.D.S a month ago
2) have a little bit of prep still to do to on the car
3) as Mallory is towards the back end of the season I've been told there will be less competitors as the season progresses and cars inevitably fail, engines break etc the field reduces in size so there will be less for me to hit
4) I'm 30 in August so it's bit of a birthday treat to myself

Plan was to compete just the once this year to get an idea of where I am, what the car is like etc and then do track days and get tuition over Autumn/Winter and tweak the car ahead of next season.

[SFurness]

Hi Mac,

Mallory is my local circuit and I will be there for that weekend, I'll look you up on the day. Sadly I'm not racing.

A couple of years back I did a "what to do on the day" for a friend who was doing his first race, amazingly it covered three pages. If you PM me you're email address I'll send it on to you.

Steve

[Mac944]

I would really appreciate that! Thanks!

Just sending PM now.

[Paul D]

I've been looking at options for accurate speed readings too, and if you don't want to spend out a fortune just to know how fast you're going in the pit lane (and I don't!), then the cheapest option does seem to be one of those little speedos designed for bikes, quads, etc. I imagine it's as accurate as your programming of it - that is, make sure you tell it the correct tyre circumference and it should read accurately. I've seen them on eBay for around £40. However, they only seem to come with about a metre of cable to the sensor, so you may have to lengthen this to reach one of your road wheels.

However, in the meantime, you could always do what I've done in the past: take a bog-standard satnav out with you in qualifying, have it pre-set to show the speed. Then, when qualifying is over, on the slowing down lap (and assuming it's safe to do so), just get your car into second gear with the pit lane speed limit showing on the satnav (give the speed reading a couple of seconds to stabilise, as GPS takes a while to catch up if speed is changing rapidly), and simply make a mental note of what revs this equates to. Once you have that info, then all you need to do is get down into second entering the pits, and sit just below those revs - sorted!

[Mac944]

Hi Paul, I had toyed with the idea of using sat nav actually and that's a reasonable compromise why I may do, in fact I'm hoping to go to Mallory to do a track day before that race so could probably use that method and take a note of gear and rev combination.

When I used to work in a certain well known bike shop/motor factors in my teens/early 20's I'm pretty sure the higher end cycle computers were wireless, whether the signal will work through several layers steel I'm not sure but it might be worth a punt.

[Mac944]

Originally Posted by Mac944

Hi Paul, I had toyed with the idea of using sat nav actually and that's a reasonable compromise why I may do, in fact I'm hoping to go to Mallory to do a track day before that race so could probably use that method and take a note of gear and rev combination.

When I used to work in a certain well known bike shop/motor factors in my teens/early 20's I'm pretty sure the higher end cycle computers were wireless, whether the signal will work through several layers steel I'm not sure but it might be worth a punt.

Just had a quick look and it appears Halfords sell wireless cycle computers for £24, might give that a go over the weekend.

[Paul D]

Yes, just had a look too, as £24 seemed too good to be true!

The only problem I see with those wireless ones is that it appears from a quick look at the installation manuals that the speed sensor has a maximum transmission range of 70 cm - which means the speedo itself would have to be mounted within that range. Not possible methinks if the speed sensor is on one of the road wheels. Well, at least, not possible if you actually want to be able to see it when driving!

[Mac944]

After a bit of digging online it appears it is possible to use the wire from a wired computer to connect to wireless sensor which extends the range from the end of the wire so about 1.4m total or alternatively just use a cheap wired computer and extend the wires, solder and use some heat shrink rubber to keep the weather out. The latter sounds a bit more robust.

[Paul D]

Yes sounds feasible. But I've been having a look on eBay (at two o'clock this morning!) and I've found one that comes with two cables - a one meter length for front wheel use, plus an additinal two metre length for rear wheel use. I reckon if you used the wheel nearest the location of the instrument, the two metre one might just about do it. Saves having to mess around lengthening wires, and it's only £16 all-in!

Have a look here if you fancy it: http://www.ebay.co.uk/itm/3307560028...84.m1423.l2649

It's too late for me now in time for Anglesey tomorrow, but I think I might take a punt and fit one before my next outing - not too much to lose if it doesn't work out is it?

[Mac944]

Good idea! Will try that too I think!

[Dom]

If you know your gearbox ratios/final drive/tyre dimensions you can use an online wheel speed calculator to give you the revs at an given speed in gear. Saves buying any GPS gizmo and is probably more accurate.

[Mac944]

I have no idea what the gear ratios and final drive will be. I suppose if I get really stuck another option is to find a quiet spot in the car park and drive beside a road car and make a mental note that way.

[MGDavid]

Originally Posted by Dom

If you know your gearbox ratios/final drive/tyre dimensions you can use an online wheel speed calculator to give you the revs at an given speed in gear. Saves buying any GPS gizmo and is probably more accurate.

exactly what I was about to post!
in the 924 driver's handbook there are some rather splendid graphs of speed vs. revs in each gear, mine's away in storage but IIRC 60 kph = 3500 rpm in 2nd gear. Job done.

[Lancsbreaker]

As Paul D said before he came over all excited by Ebay, pretty easy to work out your revs in say 2nd gear for any particular speed - ask another 944 driver to pace you if necessary - but we never had a problem anyway - just take it steady (the pit-lane tends to be fairly busy, and at Mallory, very tight) and a few seconds lost won't be critical....much better to spend your time practicing getting out of the car and back in again....and making sure your car will start when stinking hot......it took a good few times when a push-start was needed before we got that sussed........in our case, turn off engine, but then switch on ignition again to keep the fuel pump recycling the fuel so it doesn't evaporate....may be more of an issue with a turbo?

[JohnD]

Another way to calibrate your speedo or rev counter would be to use the distance marker posts on the motorway. At 100meter intervals, count how many you pass in a minute, or else how long it takes to pass through ten of them, a kilometer, at a constant speed and do the maths.

If the pitlane is limited to 40mph (?) and the Mway to 50, you would need to do some further maths to find the necessary pitlane reading.

John

[MGDavid]

Originally Posted by JohnD

.....
If the pitlane is limited to 40mph (?) .......

John

keep up at the back
it's 60 kph...

[JohnD]

Making the maths that much easier!

Thanks for the correction, David - now I know why I keep getting drive throughs.
John

[AndyV]

When you have worked out your speed/rev combinations put it on a sticker on the dash. You will forget it in the heat of battle!

Andy

[Mac944]

So just to clarify 3,500 rpm in 2nd gear should be approx 60kph/40mph in a 944?

Are all pit lane speed limits on CCSC calendar 60kph?

If that's correct I'll just put a marker on my rev counter.

[Paul D]

No Mac, not necessarily all the same at 60 Km/h. Anglesey on Saturday being a case in point - pit speed limit was 50 Km/h there for whatever reason the powers-that-be decided. And I seem to remember Mallory may also have a lower limit as it's tight there too. Possibly Cadwell also, as that's tight and short.

So it probably is best to have some kind of speedo I reckon.

But if you are going to just go with a revs for a given speed arrangement, then I can confirm what AndyV says above - have it clearly marked on the dash where you can read it, as you will forget it in a race situation!

[Mac944]

Ahh I see! Thanks!

[Mac944]

Hi Guys,

I just wanted to thank you all for your help, I competed at Mallory last weekend in the CSCC Future Classics series. It was a fantastic day and the sun was shining.

I qualified a little lower than I was hoping down in 22nd (of 24) but thanks to a slick pitstop and a few of the faster guys either dropping out with technical issues or being disqualified I managed to finish in 12th (of 17 finishers), which I really pleased with given it was my first race and only my 4th time on a race track so all in all a good weekend.

I have a vid here too (there are some hairy moments coming out of the hairpin on three occasions where I powered down a bit early and lost the back end, was fun to catch though).

Thanks again!