Engine : 1590 CC D16A6 with 272 cam.

I am going to get a manifold from Bogg Bros. Now the question is to whether to use the CBR600 F3s (35mm venturi) carbs or buy another set of R6 carbs (40mm)..

Will the 4 X 35mm be adequate?

Any advice is much appreicated.

I'm running zx7r's on my allegedly tuned 1600 pinto....38.5mm venturi's and they're running fine....would have thought 35 was a little small and 40 a little large....Oli.

Thanks Oli..

The thing is I got the CBR600 F3 carbs for a bargain.

The standard dual carbs I have at the moment are the Keihin CV carbs with 2 35mm throttles. Would my theory prove correct that if I used 4 X 35mm each port is now double the allowable flow?

Or, 1 X 35mm feeding 2 ports, but only 1 port is sucking at any one time is still 1 X 35 per port..I hope you understand what i am saying.

The car is pulling really well from 2000-6000 but sort of dies off after that, even with cam timing retarded it loses out in the higher rpm.

I hate to get the CBR600 F3s sorted out only to find it is still the same as the originial dual carbs..

Compare the power output of the bike they came off to what you are expecting/hoping to achieve. This should give you an idea if they are within the right ballpark.

You can't make carb/throttle body size much smaller simply because there is one per port. Whilst the average air flow is only a 1/4 of the total engines requirements, the peak flow is about the same for a four cylinder engine.

The engine in standard form is around 115bhp. With the 272 cam I am expecting around 130+..

The CBR 600 F3 were rated at around 100bhp..meaning I am well off target!..damn..

I think you'll be alright with the F3 carbs.
Bear in mind that, if you went with a pair of Weber DCOEs, they (40s) would be running 32 - 34mm chokes.

Right!!! It is not the thottle max opening right? It is the smallest part..I think it is 35mm, I suppose your F3s are also 35mm.

Steve at Bogg Bros said it will be ok...38..is also ok..and 40 is ok..they are able to get any carbs working :-)

Though I am in Hong Kong, I am coming back in Xmas to visit them and get the manifold fabbed up + a reject.

Great guy!

+ rejet (typo)