increasing general performançe...

The place for everything non E21. Now with dedicated E12 & E30 sections
Giorgio
E21 starter
Posts: 36
Joined: Tue Jan 04, 2005 11:51 pm

Post by Giorgio »

Somebody told me that to built 2,3 i have to change crank+pistons+conrods.We have the higher conrods? if i remember well.The crank is the same?If i need only conrods,i will buy them tommorow.Also the pistons are in good shape,but i can buy a new ones.You have bought anything?I only the a-n with the carbon inlet,new oil pump and hoses.I have change water pump.What you suggest?Chain tensioner kit?


Giorgio
E21 starter
Posts: 36
Joined: Tue Jan 04, 2005 11:51 pm

Post by Giorgio »

The change of TB is worth?The man who will fix my head told me that he can also do the TB 48 with inox butterflys.I have only to take the gasket but he can try to open it
france320isco
Upcoming E21 fanatic
Posts: 68
Joined: Sun Feb 06, 2005 3:28 pm
Location: rome

ATTENTION!

Post by france320isco »

Giorgio wrote:The change of TB is worth?The man who will fix my head told me that he can also do the TB 48 with inox butterflys.I have only to take the gasket but he can try to open it
My expert has phoned me and told that also the crank is different in fact to have the same M3/320is TDC piston position with a LONGER stroke you have to cut not only the lenght of the rod but also to INCREASE the lenght of the rotating part of the crank (the one connected to the rod, in italy we call it manovella).
If you only shorten the connecting rod, you're going to lost compression cause the piston TDC position is lower than normal.

So you have to change both rods and crankshaft.
The main bearing shell, rod bearing shell, the pin and the snap ring M3/320is are the same.

Can't help about 48mm conversion, maybe porting the head.
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