Salvadori

I've been racing Sirio engines since October last year. I have 2 Evo2 one EFRA and one IFMAR and just bought a Mario Collari modified EFRA. I've tried all these pipes with them:

Novamega TPO2
Novamega TP03
Novamega TP04
Yokomo M.Mielke In-Line
Sirio S12-200006 In-line
RB Concept E1751-193402 In-Line
Mugen P01002 In-Line


Depends on the track layout, but the best allround performance is between the Novamega TP03, The M.Mielke and the Sirio pipe.
Last race I tried the Mugen pipe, and although it gave me more top end, i think i lost low end. Maybe I need to gear the car differently I'm not sure.
After doing some more research I've been told by Sirio drivers in Europe that the best pipe is Sirio's own and that I should try experimenting with header lenght, so I've decided to try again with the Sirio pipe modifying a bit the lenght of the header, because I've been told that Sirio makes spacers to adjust this lenght, and maybe this way i'll find proper tune of the pipe for my track.
Why I have concluded on this, after my conversation with friend drivers, is because Sirio engines have a mid sized conrod (like Picco engines), as oposed to short conrod that all new Nova based engines have, so stroke, beeing the same in numbers, provide different powerband outputs.
So because of that, I think almost every new pipe out there is designed for Nova based engines, and makes Sirios loose low and midrange power, delaying the transition on to top end, thus making you feel that the engine lacks top end.
Sirio engines have their powerband at a different point, which makes it need a pipe that quickly gets the power of the engine on to the pipe's tune to have a perfect low to high acceleration.
So after experimenting more with my Sirio pipe, the only other alternative would be to try Picco or Orion pipes, because their engines have similar stroke design as the Sirios.

Hope this helps you

AFM