FD for hillclimbing
Turbo Mini Forums

I'm going through the mini at the minute getting everything as good as possible for doing a season of hillclimbing.

Currently got a semi-helical 3.9 in which at roughly 7k (which is where my power starts to drop off - another thing to look at this winter) is basically 100mph.

Now is this too low for hillcimbing? I'm going to be doing the Auto66 championship, so scarborough, harewood, elvington, cadwell and a couple of others.

I have a 3.1 which i was going to go to which gives circa 120 at the same rpm, but since never having done hillclimbing, dont want this to be a disadvantage in the slower speed stuff.



I have a feeling the 3.9 is about right, if i can maybe re-time the cam and get the redline to circa 7500-8000 whilst keeping sensible power.

I run a 4.2 on 13s. top speed 107 mph. I reach this at Pod and MIRA.

Some hills don't even require 4th.

What class are you runninhg in Iain?

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

What class are you in and what engine are you using if you dont mind me asking?

Wil,

No idea which class to be honest! I'm guessing i'll be put into sports libre?

It will with the 1293 turbo though so dont fancy my chances at all. This season is about just getting into it, then if it all goes to plan i fancy going for the under 1400cc with a non turbo K headed engine.

Sounds like my 3.9 is spot on then.

I dont think you will get near 100mph at Scarborough but it will feel like 200mph
I have done the Scarborugh hill a few times wiith my Vauxhall mini but I havnt used 5th gear I think about 85-90 mph will be the max.
Allan
Ps Hope to see you race

http://www.rabdunn.co.uk/

No as Will says 3.9 too low for hillclimbing - fine if there are circuits involved but I would have said 4.3

On 5th Sep, 2011 Vegard said:
I stand corrected. You should know

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Yeah i do have a lot of mid-range torque, in fact at the minute make peak power/torque at 6k as it comes on boost just before 3k.

I'm on 10's as well which makes a small difference.

I think i'll try it (especially as its the only semi-helical i've got) and see. There are quiet a few sprints on circuits in this series:

Croft
Elvington (not a circuit but similar)
Three Sisters ?

with the others being

Harewood
Scarborough

I used a 3.9, then a 3.6 now I use a 3.44, times always got better as diff ratio got lower. I find it much better to use the torque than revs. I also always machine the centres out of a standard helical crown wheel and pinion set rather than use a proper LSD set which is bloody expensive, the 3.44 when machined with just fit on a quaife diff.

Interesting stuff there graham!

Well i'll try the 3.9 for the minute as i think the 3.1 would be a bit extreme. at least its fairly easy to chance between meetings, or at them if i want.

Changing FD at a meeting? Christ that is a bit keen......

I think the thing to bear in mind about Graham, is that, as far as I know he only competes at Curborough. Which has no hills (well the molehill, but you're supposed to around that)

If you go too tall, you'll bog at the Mere hairpin.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Only a 2 dayer Tom

I'll see with the 3.9 how we go. Need to get my in gear boost control sorted this winter as well.

Many moons ago in MOT I hillclimbed, I started with a 3.44 on tens but changed to a 3.6 which was better. I never realy took it that serious but was fun.

There is some seroius machines out there so just enjoy it!

JF.

trust me, i'm going to

the idea is to try and get as good as i can this winter so i have as little to do inbetween races as possible!

ive been using a 3.9 in the clubby for sometime, not too bad on hillclimbs but better suited for sprint tracks like crborough, i top out coming up avon rise at combe!

The local sprint circuits for me are lyddn, goodwood and brands...

Not sure I can afford to go racing in 2009 (again I know I know)...

But getting bored of just trackdays - been doing them 13 years at some point next year :o

Maybe I should pull my finger out and finish my racing mini and go sprint it!

AlexF

Your Choice of Final Drive ratio should also take into account the size of wheels / tyres you are using , most tyre maufacturer websites have info on diameter , revolutions per mile etc . Gearbox - Formulae for FD/tyre size/car speed and gear ratio calculation can be found on Calvers website

lol

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

is this the imfamous one that uses piublished tyre hights and not rolling radius.

when ever ive bought slicks they have been pre mounted and have there acctual circunference marked,

i used to use a 4.9 cwp on the DON 15 years ago

WWW.FORCE-RACING.CO.UK PLEASE CLICK HERE

Yes you can get the info on the tyre you actually buy, but Avon in particular never seem to make the same tyre twice.

http://www.twin-turbo.co.uk
http://www.hillclimbandsprint.co.uk/default.asp

A man without a project is like a like a woman without a shopping list.

Iain Oliver Mount have a 3 day meeting 2nd-4th may next year
That will give you time to change the FD a couple of times
Allan

http://www.rabdunn.co.uk/