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cewrx7r1 · 03-15-2008, 11:53 AM

I grew up on carbs. Both my Alfa Romeos had twin Weber 40DCOEs.
They ran great and made beautiful sounds. That was two 40DCOEs for 1299 cc of displacement with 28mm chokes.
Later used 32mm for my autocross prepared car/engine.

When I modified my 83 FB: rally port, headers, complete exhaust system, changed distributor advance curve, etc; I used a single Weber 45DCOE, with 42mm chokes. It ended up taking much of my time and modding of the emulsion tubes to run almost perfect. Why, the 12A really needs two 45DCOEs. Has to due to low internal fuel capacity for transistion from idle to main jets.

With what I know today and available WBs, FI would be so much easier to tune and more precise with more power.
Thus I would use the WEBER as only a TB and conveted to FI.

FI can compensate for air temp changes but the Webers don't. I never seen a carb with an air temp sensor.

03-15-2008, 11:53 AM	#7
cewrx7r1 The Judge Join Date: Feb 2008 Posts: 196 Rep Power: 18	I grew up on carbs. Both my Alfa Romeos had twin Weber 40DCOEs. They ran great and made beautiful sounds. That was two 40DCOEs for 1299 cc of displacement with 28mm chokes. Later used 32mm for my autocross prepared car/engine. When I modified my 83 FB: rally port, headers, complete exhaust system, changed distributor advance curve, etc; I used a single Weber 45DCOE, with 42mm chokes. It ended up taking much of my time and modding of the emulsion tubes to run almost perfect. Why, the 12A really needs two 45DCOEs. Has to due to low internal fuel capacity for transistion from idle to main jets. With what I know today and available WBs, FI would be so much easier to tune and more precise with more power. Thus I would use the WEBER as only a TB and conveted to FI. FI can compensate for air temp changes but the Webers don't. I never seen a carb with an air temp sensor. Last edited by cewrx7r1; 03-15-2008 at 11:58 AM.