Changing from 4 speed to 5 - worth it?

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mariner
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Changing from 4 speed to 5 - worth it?

Post by mariner »

Hi all. I'm thinking about changing over my four speed gearbox for a 5 speed and would be interested in people's thoughts. My knowledge in this area is very limited!

I'm assuming that following the conversion (done before I bought the van) the original gearbox was left in. Is there any value in changing this? Currently I get around 250 miles from a tank and the main reason for the change would be to increase this.

I've been told it's relatively simple - is this the case? Any suggestions on where to source a 5 speed and what exactly I'd need? My intention would be to get the necessary parts and then hand it over to a garage to get the work done.

Any advice/help welcome!
1985 Super Viking with Subaru EJ22 (formerly 1.9 petrol DG)
1981 air-cooled 2.0 high top

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Titus A Duxass
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Re: Changing from 4 speed to 5 - worth it?

Post by Titus A Duxass »

It's not really worth.
Take a look at the gear ratios and you'll see that there's is not much difference between the 4 and 5 speed boxes.

http://rjes.com/html/gearbox_types.html" onclick="window.open(this.href);return false;

And you'd need to source a 5 spd stick and tower along with some of the shift rods.

Unfortunately it will not be the magical cure that you seek.

You could probably get a bit more by putting larger (diameter) wheels on.

The Subby is not reknown as an economical motor and putting it in a 2 tonne bus is going to make it any better.
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shepster
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Re: Changing from 4 speed to 5 - worth it?

Post by shepster »

Fit slightly bigger profile tyres on, there's a calculator around somewhere.

Increase the overall rolling diameter a tad.
2.1 DJ running on carb and LPG.

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R0B
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Re: Changing from 4 speed to 5 - worth it?

Post by R0B »

I doubt you will get much more mileage out of it whatever you do to it. Assuming its set up right.


250 miles from a tank and the main reason for the change would be to increase this
2.1 LPG/Petrol Auto Caravelle

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mariner
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Re: Changing from 4 speed to 5 - worth it?

Post by mariner »

Thanks for the replies guys. Doesn't seem worth the effort right now!
1985 Super Viking with Subaru EJ22 (formerly 1.9 petrol DG)
1981 air-cooled 2.0 high top

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