fitting a 948 engine

[ampwhu]

hello. i want to change my engine from an 803cc to a 948cc. can i use the engine backplate, flywheel and clutch from the 948 or do i need to transfer them from the scrap 803 engine onto the 948?

i am fitting an SU carb, spin on filter and duplex chain at the same time. i presume my 803 box will be able to handle the 948 as well.

thanks

[ampwhu]

anyone able to advise please?

[PSL184]

I'd fit a 948 box at the same time. The gear spacings on the 803 box won't suit the bigger engine. Duplex chain not necessary either and all A series had an SU carb so not sure what you mean there?

[bmcecosse]

Well no - the 803 engine in the A30 had a Zenith carb! Yes - you can use all the 948 stuff, but as PSL says - the 803 box will soon break, so look for a smooth case 948 box, or even a ribbed case 1098 box. The 948 box can take the 803 gearlever if you want to be 'original'. It is also possible, but not so easy, to use the 803 lever on the 1098 box. Main thing thing you WILL want to change is the rear axle final drive ratio! It's criminally low in the 803 engined cars. And - don't worry about duplex chain - that's for use with heavy duty springs/high lift cams. If you want silence - the Mini style single chain with tensioner is the way to go.

[mike.perry]

If you fit the 948 box and remote shift thn you will need to cut back the floor pan and fit the 948 gearbox cover panel and if you change the diff then you should also change the speedo. Also take the opportunity to upgrade from an SU H1 to an HS2 carb

[ampwhu]

Well no - the 803 engine in the A30 had a Zenith carb! Yes - you can use all the 948 stuff, but as PSL says - the 803 box will soon break, so look for a smooth case 948 box, or even a ribbed case 1098 box. The 948 box can take the 803 gearlever if you want to be 'original'. It is also possible, but not so easy, to use the 803 lever on the 1098 box. Main thing thing you WILL want to change is the rear axle final drive ratio! It's criminally low in the 803 engined cars. And - don't worry about duplex chain - that's for use with heavy duty springs/high lift cams. If you want silence - the Mini style single chain with tensioner is the way to go.

ok then. how would i transfer the 803 long gearstick onto the 948 box. is it a simple bolt on job or is there a kit to buy? i don't want to alter the car or cut any panels etc.

thanks

[David53]

I'm curious about this also......one day I may need to fit a 948 (1098's were never sold here) and would prefer to retain the look and feel of the car. I am presuming you simply remove the remote box on the 948 gearbox and fit the long throw gearlever directly to the box?

[mike.perry]

John Evans (advert in Minor Matters) supplies a 1098/803 shift conversion. Perhaps if you contact him he will advise whether the conversion is possible on a 948 box.

[ampwhu]

John Evans (advert in Minor Matters) supplies a 1098/803 shift conversion. Perhaps if you contact him he will advise whether the conversion is possible on a 948 box.

how would i contact him. whats minor matters?

[Fingolfin]

Can't tell you how to contact Mr Evans, but Minor Matters is the club magazine. I don't personally get it (as I haven't the money for a membership yet ), but I understand it's rather useful to the community.

[bmcecosse]

This has been gone over many times before. To use a 948 box you simply remove the rear part from both boxes and swap them over. So your first step is to secure a good 948 box! You say no 1098s around - but for others interested, it IS possible to fit the pudding stirrer lever to a 1098 box - Callyspot did it a while back - some slight 'fettling' was involved, but nothing too major if I remember.

[David53]

Interestingly enough if I did elect to go down this road, fitting a 948 engine and box, the diff in my car would suit as it is the earlier split case MM diff with the higher ratio, the same ratio as in the 1000.

[bmcecosse]

I presume you mean 'lower ratio' as in 4.55 or even 4.22 rather than 5.3 ?

[David53]

Yes, sorry. The MM style back axle is 4.55 which I believe is the same as a 948 car? So theoretically I could fit the 948 engine & box?

[bmcecosse]

Indeed - but for easier cruising a 4.22 would be better!