Engine/gearbox swop tips needed (apart from nooo dont do it)

[dochie]

Hi Guys

I have just bought an MGB engine and o/drive gearbox to put into my Riley as my winter project and according to the ID numbers they came from a 1975 car.

I was wondering if anyone on the forum has done this conversion already and could give me a heads up on the pitfalls I am going to encounter.

Had a quick measure up today and the engine side seems doable - change the front engine plate to suit the engine mountings, use Riley exhaust manifold and thermostat housing. Is that about the main bits or is there more to bite me ?

However the gearbox seems to be the more difficult part  -  Does the bell housing need a cut out to clear the steering rack ?    Will the box actually fit the tunnel ?

From my quick measure the gear lever will be about 4 inches further back and will foul the handbrake, so whats the best way round this?  Maybe shorten the remote?  Maybe shorten the handbrake ?  Move the handbrake?

Then we get to the gearbox cross member, do I modify the Riley one, the MG one or make something new

I know there are other bits and pieces to do but if anyone can point me in the right direction for the major bits it would be much appreciated.

Sorry if I have offended any purists out there

Duncan

[falconriley]

You need the gearbox which has the cut out for rack clearance. I don't know if the MGB can be modified, as I just used the original gearbox behind the 1800. It simplified the whole job so much that it made sense. I do know that the bellhousing needed metal removed to clearance the diaphragm clutch. If you use an engine without the diaphragm it might not even need that.
Matthew

[dochie]

Hi Mathew

Thanks for the reply

The main reason for the swop is to raise the gearing and make motorway driving more comfortable.

My options appear to be the Ford type 9 with the associated fitting kit, or the MGB overdrive box.

Finances dictate that the MGB box is my best (only) option, and if I'm going to fit the box I may as well fit the engine.

Thanks again

Duncan

[canuck]

A member on this 'old forum' did have a Riley with an overdrive transmission fitted. It required some cutting of the tunnel & floor pan and of course a bespoke bit of metal work to cover it all up.  I can't remember what this floor & tunnel metalwork did to the seat locators but I recall something funky needing to be done.
The 1800cc engine would not react nicely to the Riley exhaust manifold, which is much smaller diameter than that of other 1800cc fitted cars. Of course a larger diameter  exhaust system will be needed.
I am fitting a 18G engine to my Riley however will use the current Riley gearbox and rely on the added torque to see me through.  I could not find a suitable exhaust header to fit so I had a custom 'sexy' shaped tube one welded up.
I recall Roger (Noddy) has a successful fitment of a MGA cast header. His first try was a bit odd but I think he sorted it since. 

The Achilles heal of a 1800 transplant to the Riley remains the delicate rear axle shafts!

B

[dochie]

Hi

Thanks for the reply but that was the news I hoped I wouldn't hear as I really don't want to hack the tunnel and floor pan.

The Riley manifold will get me up and running and I already have a large bore stainless system fitted so in the future I could address the manifold problem.

I read an old post on another forum and someone was saying they fitted the mgb engine and box into a riley 1.5 with only a cut in the bell housing and a modified cross member. Said the job was done in two days but the post was short on the details I was looking for.

The rear axle problem could possibly be overcome with competition half shafts.

Thanks again

Duncan

[canuck]

Duncan
I am thinking the MGB gear box 'sans OD' will fit, as the article you mention calls up.
When one tries the OD gearbox unit it adds bulk at the rear end of the gearbox, hence the need to hack into the metalwork.
However done smartly, I think this is a nice upgrade.

B

[timchris]

Ours has a MGB 18V engine and type 9 box. I seem to remember using the Riley bell housing, but it did involve some swapping about with flywheels and ring gear. And i had to add a couple of inches into the trans tunnel to make it wider.

[dochie]

Hi Guys

Thanks for the replies, it looks like I will have to make it up as I go along.
The engine I bought was reputed to be running well but I took the head off the other day to check and it was good news as the bores looked good and the pistons were marked + .030
Today I took the sump off to check the crank and bearings and they were stamped .010 so it looks as if the engine has been overhauled at sometime in its life.
All in all it looks like £100 well spent as it came with all ancillaries.

Duncan