Hi all. I have an 02 mk1 octavia 4x4. i like the short ratios but i think it could do with a slightly longer top gear. (To save fuel mostly)

I have been thinking about how easy it would be to fit a 6 speed gearbox from an Audi s3 or TT.

What extra parts do I need? Do I need to change the rear diff to match the gearboxes final drive ratio? What gear linkage and drive shafts do I need?

Thanks for any help

Nick

have you thought of fitting a tall 5th?

Fitting a 6-speed 02M from a petrol car won't give you any more top end, you'll just have to change gear more often. Fitting one from a diesel car will give you longer legs, but you might not have the torque if you're not heavily modified.

You can make a 6-speed 02J if you really want to ( http://www.quaife.co.uk/shop/products/qke2v ). Money!

I'd imagine the RS (or some other VAG vehicle) 5th gear is slightly longer. But is it really worth the hassle?

But is it really worth the hassle?

No

No point as the 5th in a long 5 speed box will give no mpg benefit over a 6 speed box. 6 speed box is mated to the ko4 while the ko3s is suited to the 5speed box

As said, both top gears are same ratio so just changing gear more often. If you did swap you would need EVERYTHING that touches the 'box also: gear linkage, starter motor, clutch, driveshifts and front end of a tt prop shaft.

Thanks.

Does that mean that the rear diff ratio is the same as a TT/s3?

Has anyone tried fitting the 5 gears out of a Vrs into a 6 speed diesel box, leaving the 6th gear the diesel ratio? Just wondering if its possible?

Sent from my Galaxy S2 not a Crapple!

What extra parts do I need? What gear linkage and drive shafts do I need?

most of these already mentioned:

driveshafts

propshaft (front section of S3/TT/R32 prop mated to rear section Octavia 4x4)

engine to gearbox mount (should be attached to gearbox, but can go missing)

clutch

paddle selector

starter

Do I need to change the rear diff to match the gearboxes final drive ratio?

No

The transfer box with drive ratio's is mounted to rear of gearbox, before the prop.

The haldex clutch takes care of the rest

Has anyone tried fitting the 5 gears out of a Vrs into a 6 speed diesel box, leaving the 6th gear the diesel ratio? Just wondering if its possible?

Not specifically tried, but yes, can be done.

Would probably be cheaper + better to start with petrol 6spd O2M though. Mix and match.

This is sort of along the lines of ratio's in my box

But is it really worth the hassle?

From fuel economy angle, the petrol 6spd O2M, no

imo your money would be better spent putting the longest 5th possible in your existing box

Using an O2M box does open up the choice of LSD's you can stick into the box though.

I fitted the 6spd more for strength reasons after destroying the 5spd in my 4x4, I did notice an improvement in economy though? I thought the top ratio/final drive was higher on the S3 than the 4x4 octy?

No point as the 5th in a long 5 speed box will give no mpg benefit over a 6 speed box. 6 speed box is mated to the ko4 while the ko3s is suited to the 5speed box

mk1 LC has a K03s and a 6 speed box

I fitted the 6spd more for strength reasons after destroying the 5spd in my 4x4, I did notice an improvement in economy though? I thought the top ratio/final drive was higher on the S3 than the 4x4 octy?

It is, but only slightly

as a pure exercise to get better fuel economy, the cost of swapping to a 6sp box would probably negate value of fuel saved (unless you where doing huge miles. got free box, etc, etc)

If you've got to buy all the kit, then pay someone to fit, you're going to have a hole in your wallet, probably circa £1K wide

LPG would probably be a better investment

Thought so as I know it's not wishful thinking due to the weekly fuel logs I keep.

:yes: LPG is by far the best thing for the 1.8t. The engine is about as ideal as can be for conversion. Hard valves and with a modern system power is very good

I used to get on average about 33mpg on a 23 mile A/B road commute, from my 4x4, which had vRS internals fitted. Pulled 3500 rpm at indicated 80mph whereas I gather the standard box would be on 4000 but given the bhp/torque mine was running, it worked well.

By all accounts, mpg was about 2mpg better but it's need to run 97RON or better, negated any saving really.

So, I too would also advise against it, given the gearbox rebuild / swap cost.