54mm Throttle Body advice.

I now have in my possetion a spare set of 51mm TB's.
My plan is to have them bored out to 54mm, and I'm just looking for any best advice or suggestions.

Things I have read / noticed.

There are a few discussions regarding the bore size at top and bottom of the bodies.

Obviosly the tops need to be 54mm, and I assume that they will need to taper down to somewhere close to the original bottom size. (about 48mm) This is so they still match the inlet manifold rubbers. Is this so? Are there any other inlet manifold rubbers that would better suit?

Any advice and suggestions on where to get 54mm butterflies? I did a bit of research and understand that SP2 and SV1000 have 54mm bodies but I dont think u can buy the butterfys. ??

Velocity stacks. Standard bored out or some new ones? I have seen some slightly shorter ones that may go well with the larger bodies.

I've just read a very interesting discussion on apriliaforum.com which raises some intersting points.

Sounds good. Who did them? How much?

cheesy said:

damage

If ya can afford to do it
get some tried & tested ones from Ken Zeller in the states on exchange
he'll even supply the stacks to match

Click to expand...

I would probably find it dificult to afford or justify at the moment. Also I'm a bit of a nerd sometimes and it sounds an interesting project to have a go at myself.

PS Ken Zeller was making some interesting comments in the discussion I was reading on the aprilia forum. I think I have a good idea how to make it all work. . . . maybe . . .

It could be, but they fetch a high price. Wont cost me much, £25 for the bodies, A beer for the machining, $40 to ken for the butterflies, and probably a few weeks pissing about trying to get them working properly. . . .