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MG MGB GT V8 Factory Originals Technical - 4.0 convertible to distributor sys?

I have found several engines.

I am inclined to go with the 4.0 for the bottom end strength and the capability of converting to the 4.6 (crank kit).
My query is, can the 4.0 be converted to a distributor type ignition system by simply bolting on a timing cover from a 3.9?
I can not seem to find any info on this on the net.
Thank You.
jegawatt

Yes
you will also need to use the 3.9 style cam of course.
The crank is also slightly longer on the 4.0 so you will need a spacer making for the front pulley.
Just bolt it on.
Mark
Mark

Thank you Mark,
I am going to purchase the "How to tune a Rover" book (or something to that effect), as I am still familirizing myself with this engine..and I must say I have learned quite alot online(messageboard archives, etc).
I am about to purchase this motor (next week), thus need to know what is compatible..I have a choice of two 3.9 engines and one 4.0
My final (?) question is, which oil pump is used?..I know the 4.0 use's a different oil circuitry, would this mean that the 4.0 pump is retained?

P.S. Someone must sell a kit for this conversion
jegawatt

disregard my last post
I have decided to go with the 3.9, as I do not think I will ever want to stroke the engine..I really like the 3.9's stroke:bore ratio.
jegawatt

whichever cover you use will determine the water & oil pump. The water pump base is part of the timing cover & there is no interchange of pumps between the serpentine cover & the earlier GM style in its several versions.

With the GM style cover, you have some choice. You can use the 215, 300, or 300 A/C water pump, as well as the Rover water pump. You must match the water pump pulley to the crank pulley based on the water pump you use. The Rover pump is the longest snout, next the 215, then the 300 Buick which is the shortest.

Oil pump base is cast into the cover as well, so the cover you use will determine the oil pump. With the GM or early Rover cover, you can use the stock pump, or the GM "metric" pump which turns the filter to a better angle.


Jim Stuart

Now you have me looking at the 4.0 again, hehe..thanks Jim
jegawatt

On the 4.0 if you change from the serpentine cover will you have to change oil pan also? I know on the 4.6 the pan has to be changed.
Ozzie

3.9 4.0 4.6 5.0?

http://www.v8engine.com/homepage.htm

or

http://www.v8developments.co.uk/5_0_std.htm

Paul

Paul

Why would you have to change oil pans? I don't have a 4.0 yet, but I used the same pan on my 4.2 with a serpentine cover & a Buick cover. If the oil pan gaskets are the same, the pans should interchange, unless the 4.6 needs a deeper pan due to the longer stroke. With many people stroking the 4.0 using a 4.6 crank, this has never been mentioned.
Jim Stuart

I came across this serendipitously--what a piece of work(for a V6 that is)...
http://www.taperformance.com/v6_block_flyer.htm
jegawatt

This thread was discussed between 15/02/2004 and 19/02/2004

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