Which road to go down?

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Boomlander
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Which road to go down?

Post by Boomlander »

Hi Folks,
Been considering what to do in the near future - Jethro has a 948cc engine with the original long stick smooth gearbox which I assume was originally coupled to an 803cc motor.
When it comes the time to have the engine main and big end bearings renewed should I have the existing gearbox overhauled at the same time or exchange it for a remote stick type.
Are there any known problems running with the old style box and 948cc engine?
Advice as always much appreciated. :-?

mike.perry
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Re: Which road to go down?

Post by mike.perry »

The ratios of an 803 box are not suited to a 948 engine, in fact they are not suited to anything :(
Fit a 948 box with the 803 gear lever
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bmcecosse
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Re: Which road to go down?

Post by bmcecosse »

It may already BE a 948 gearbox, that has been fitted with the 'pudding stir' gear lever. Better to strip the lot out, and fit a good 1275 engine and gearbox....and stop holding up the traffic! :roll: :lol: I'll get my coat.....
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Boomlander
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Re: Which road to go down?

Post by Boomlander »

Thanks guys - you may be right about the box being a 948, Jethro doesn't have a problem keeping up with the traffic although I wouldn't fancy a belt down the motorway (He was taken for a 50 mile run down the M1 by the shop I bought him from). :D

Boomlander
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Re: Which road to go down?

Post by Boomlander »

bmcecosse wrote:It may already BE a 948 gearbox, that has been fitted with the 'pudding stir' gear lever. Better to strip the lot out, and fit a good 1275 engine and gearbox....and stop holding up the traffic! :roll: :lol: I'll get my coat.....
If I start thinking about a new engine and box it will probably start a spending spiral with upgrades to the brakes and so on, I may just settle for new engine bearings! :wink:

bmcecosse
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Re: Which road to go down?

Post by bmcecosse »

The top gear is same (1:1) on all A series boxes. The old 803 box has horrible internal ratios - that's the problem - need to rev it like mad in second gear before changing up. If you want easier cruising you need to change the final drive ratio in the back axle - the 803 had a 5.3 ratio as standard - the 948 is 4.55 and the 1098 is 4.22. A good 948 engine will manage the 4.2 ratio - so if you do that - you will notice a considerable improvement in refinement/silence/economy! Of course - the speedo would also need to be changed to keep the readings approx correct.
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Boomlander
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Re: Which road to go down?

Post by Boomlander »

Jethro has the later type back axle and the speedo reads approx. 10mph fast.
Gearbox changes up and down fine without needing excessive revs between second and third so it probably is a 948 box.
Only problem is a whiney 1st gear and because of the lanky gearstick you have to be very careful when changing so that you do not accidentally hit 1st instead of third! :D

bmcecosse
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Re: Which road to go down?

Post by bmcecosse »

Just use 1st to get the car rolling. It's straight cut - so will always be slightly noisy.
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Boomlander
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Re: Which road to go down?

Post by Boomlander »

Thanks Roy, much obliged. :D

bjm38
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Re: Which road to go down?

Post by bjm38 »

What sort of impact do members notice on their insurance when upgrading their engine/box with bigger A Series kit? Also assuming brakes are upgraded to 8" minimum fronts for 1098.

Thanks

Bernard

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