As bro' has mentioned, we had a trip down to Russ at
http://www.m3spares.com a few weeks ago, he kindly supplied us with S50 m3 throttle bodies, an oil housing etc to try on our M54 motor - Top bloke

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Its okay seeing throttle body conversions on the internet but i could see several issues regarding fitment - No one said it would be easy

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A, they hit the cam box - unless you mis-align the ports
B, you cant access the oil filter
C, all the M7 studs clash with each other
D, ports are different shapes

After questioning our sanity, decided to push on

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An M3 housing wasnt going to help here as it was still too tall, so we looked across the atlantic for guidance on a `remote' take off point. We could just stump up $$ and buy one like this:

but with the shell away for x-mas we decided to cut a few housings up and see if anything could be done with the M54 one. After throwing some springs and 5h1t out of its internals

and giving it a trim we realised it had some potential for modding bruv's style
Some galleries need some plugging but with the aid of a drawing, machine shop and a tig man it should work nicely
..ever the optomist
Bro' has some better pictures:

We then worked thro' some drawings i did regarding an adapter plate to make the throttle bodies fit the head, i'd overlooked the shape of the cam box walls and described to bro' that it had to be a 2 part design. He bounced an idea back of having 2 plates - I'm going to draw up a proposal and report back
I had the USA S52 M3/V8M5 valve springs tested by my mate Keith, they are a thinner wire thus decreasing their compressed height (for bigger lobes) and although an improvement i'm pretty sure they wont cope with a good inlet cam. They are a progressive spring and have a near identical rate + seat pressure (as fitted) to the standard M54 ones.


Also, slowly on the move are:
Oil pump chain drive mods - as it looks a bit under engineered
Wet Sump Mods
Head port improvements, although 120 cfm @ 10" is pretty good to start with
Plenty to do.......
BTW, got the 1 year lad old out cutting his teeth on an old M50, couldnt believe it when he started moaning after 4 hours out in the cold!
...or was that 4minutes
