MGB 5-bearing conversion

I was aware the 5 bearing required considerable changes to fit the Magnette as opposed to the not so easy to find 3 bearing, I decided to proceed (at this stage, the Magnette engine remained in the car). I wanted to check compression before I proceeded, but this involved sourcing an MGB starter motor, so back to ebay again. This fitted the MGB backplate, and the testing could begin. I was getting 165 to 170 PSI so was happy with this. The head came off, new valve seals fitted and valves ground in. Being happy with the compression, I checked the main and bearings and crank bearings. All in good shape. The timing chain would be renewed anyway.

The work begins:
There is now a superb sump adaptor kit manufactured to allow the Magnette sump, and oil pump legs to align onto the MGB engine block. The Magnette oil strainer can still be used. Some minor changes need to be made to the oil pump, though I fitted a new one as a matter of course..

The dipstick hole in the block requires redrilling further towards the front.
Yes. Be careful here. I hashed this up slightly, as the dipstick should pass between the oil strainer legs (My drilling was slightly out, so it didn't!) Undeterred,.I machined a blank plug, then redrilled to angle the dipstick tube correctly (this time, successfully!)
You may need to move the stop plate in the sump here, so do check where the dipstick end rests.

Front engine side plate will require swapping to accommodate the Magnette breather pipe.

Front & Back plates:
To allow the Magnette engine mounts to be used, the engine Front plate must be fitted from the Magnette. (MGB type won't work here) likewise, the backplate will depend on your choice of gearbox. In my case, I'm using a Ford T9, so Hi-Gear can supply this for you.

Water pump Save 
You will need to uprate the water pump to MGB standard. Be sure to buy the shortest nosed pump available to give sufficient clearance from the fan blades to radiator. 
I had no issues here and plenty of clearance from the rad. My issue was the fan blades touching the dynamo pulley ! I solved this by machining a 1/4" alloy spacer to fit behind the fan. Solved !

I have retained the original exhaust for now, but intend to fabricate a larger bore system to cope with the additional output.

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