High revving 3.2: what is needed?

[911hillclimber]

I tried a 'Ferrari gate' plate some years ago, what a game and very very hard to get the 'H' shape right. Aborted in the end, it seemed too unreliable
Due to the movement of the shift rods the H is not a true H more add a V into the equation, horizontal distance from 1 to 3rd is far wider than 2nd to 4th at the gear lever.

Discussed before recently but you can get a cable shift from the States. a custom job but mounting the lever box (which is quite large) to the space I have is problematical!
Being a race car, everything is tight, small and nothing is excessive.

[fetuhoe]

I still think a CVT would be a plan

[911hillclimber]

Or a Sportomatic!

Seriously though, at Shelsley Walsh soon there is a car in my class with such a transmission on the back of a V8 two stroke.....

[fetuhoe]

Graham,

Thinking about this a little more you effectively have an H Pattern 4 speed gearbox with the reverse blanked by a strong spring and no 5th gear.

4 speed boxes don't normally need any internal gate definition as you just need to keep the stick in one plane for 1st to 2nd and then another plane for 3rd and 4th.

I would look at the Fabcar 915 shifter to see if you can incorporate some of its features into your shifter.

[MikeB]

Graham

At any point once off the line that you need to go back into 1st? If not, make a shift lock that stops you engaging it.

[911hillclimber]

Thank you both, I'll take a look Chris. The lever will not go into '5th' slot, it is blank of course.
Mike, no 1st is only for when I leave the line, never deliberately used again until coming out of the paddock or returning to it.

It would be easier to have the 1st position 'resisted' by a spring like I have for reverse selection, food for thought!

This is the shift lever..

[MikeB]

A spring loaded plate shaped like a r ( or a C on it’s side with the gap facing backwards)that slides over towards the outside once you go into 2nd, blocking the lever from 1st, but has a gap for 3rd. That means all the gubbins can be over you sidepod and not in your leg space

[904GTS]

Graham could you fit a 911 shifter on the left hand side ? you could then convert the transmission to a side shift as used in the Porsche 916, there is a kit available from Martin Bott in Germany

https://www.bugat5speed.de/en/porsche-c ... orsche-914

I haven't used this kit but have used a similar one by Vellios in the US in a 904 which worked well, but wasn't as nicely engineered as the Bott one looks.

With your car being right hand drive I would think it would be a straight run back to the transmission shift input.

Barrie

[911hillclimber]

Barrie, that was planC some time ago!
The fuel tank and the engine is in the way. The engine sits super low in the tub and the manifolds are tucked into the centre line of the block as there is very little room to spread them out by the bell housing.
It is the gap for the bell housing that makes just about rules out every modern box.

To fix almost every issue I have (ie bees in my bonnet) is a complete Boxster drive train, but that will mean missing a year out in the Lola, but could hill climb the 911 or the Boxster even instead...
I will soon go to the PCGB Club House where there is a Boxster with a wire frame 'body'.
This means I can take critical measurements of the bell housing and the distance between the output flanges of the drive shafts as well as mounting points etc.

Where the bell housing passes through is where the suspension is bolted at the rear...

[Brookesy]

Looking at the pictures I still think you cold have room for a cableshift mounted on your left and the cables can be custom made for your length to go around the oily bits.
I’ll be stripping the Nike from the dry build stage in a couple of months and you are welcome to try the shift tower to see how it fits.

[911hillclimber]

You know how tricky this lot is!
Please, I'll borrow the unit when you have it free of the car, thanks!
Graham.

[map]

Gearbox - what about a 986 Boxster 2.5 5 speed gearbox?

There's a guy raced a 986 in rallycross (or similar) with 2.5 5 speeder and that was connected to a 400bhp Turbo'd Audi V6. There's also a 986 racer running the same gearbox in a relatively "free" track series - that car's engine (whatever it is) is way over the 200bhp the 2.5l engine left the factory with.

Think they're shorter geared (1st - 4th) than 6 speeders and seem to be pretty robust - also think you've got good options in terms of locking diffs too.

Couple of "off the shelf" options for shifting to give you a very sharp and well defined shift.

Not sure what's involved with coupling one to your engine - but may be worth a look. And then if you decide to go to a "big" M96 engine you're part way there - just stick the rads in the side pods.

[hot66]

as much as I love aircooled, lets be honest these days they can be quick but theyre not modern quick, but a lot of the pleasure comes from the charactor, noise , history etc ... unfortualtely that counts for nothing in a race car if you want to be competitive. If you enjoy driving the car as it is & realisitically dont expect to be competitive then stick with what youve got, solve the gearchange issue and enjoy

If you want to be first to the top , these suggestions for alternative power & boxes are spot on Boxster motor & box turbocharge could be a fun project

Personally Id keep an historic chassis with an old school motor ( and old school driver ) and accept the only person I'm trying to beat is myself

[911hillclimber]

James, I have been in the Old Skool class/mindset since selling my hot Impreza for this Lola.
Oddly, I've had far more pots with this car than the 911 or the Impreza.
Too old and retired (cash-strapped) to do a wild change (Audi V8 and box) and too scared to go much faster, so a 250+ bhp Boxster drive train would answer all the troubles.

However, the heart says keep the old air cooled drivetrain with the magic flat fan etc and have more fun.

I will for now focus on 'gating' the box externally and taking the effort out of the gear changes, I have 100% less leverage on the change compared to a normal 911, and to solve that is easier said than done.
One last point is if I change gear slowly things improve....

[911hillclimber]

Had a closer look at why this box is so awkward to shift gear in today.
In summary I have managed to get things far better.
I started the car, up on stands and drove through the gears sitting in the car, race boots on to get 'real' feel of the shift. It was late Sept 18 when I last drove the car.

The shift from 2nd to 3rd was still notchy with a marked step when going from neutral to 3rd (from second) but not so much from 4th to 3rd.
Switched off, had a good go at the movement as slowly as I could and noticed the step going to 3rd from neutral and realised what was happening.
The linkage was actually going just to the right of the H gate so the lever was pushing 'just' against the land from neutral/3rd and the slot towards 5th. At times it would slip back to the left and go to 3rd.
This was down to the spring detent in the external mechanism (a simple compression coil spring) allowing the over-shoot of the shift rod.
I tightened all the clearances up everywhere I could and re-set the spring to be about 1mm compressed when the lever is moved to 3rd from neutral and the step is gone.

I could do with a coil spring with a stiffer rate or a greater pre load which will be the next step.

All in all a much better positive feel with scope for a bit more to come.

The coil spring compresses when you 'slap' the short gear lever across to the right to get reverse. Often I have to move the car around the paddock parking slot when I'm back down and off the hill so getting reverse is essential for my 20 point reversing to my narrow slot while everyone stares...

All this is hard to express in words, so I hope these pictures will help if anyone is watching still!