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Discussion Starter #1
Can someone here explain to me why I can't get my WEBER 13's to perform like the 152 G's? With the 13's, I get much better throttle response from idle and much punchier above 3000 rpm. Problem is I have hardly any torque down low with the 13's. Without a load, they idle better, they are much more responsive and far easier to tune so what gives? The carbs are set up the same. The 152's give me good torque from idle making them much more driveable with a cost up high. I've played around with jetting, chokes, aux chokes and I still can't figure it out.........frustrated
 

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Where are you located? What car/engine are the carbs fitted to. What mods to the engine? Which manifold?
 

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They have different progression holes.
 

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Discussion Starter #4
Where are you located? What car/engine are the carbs fitted to. What mods to the engine? Which manifold?
Pasadena. 1967 Alfa GTV 2.0 European head/manifold. Stage 4 head ported, larger valves, compression in the high 11's/1. CB cams.
 

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A wideband AFR meter will tell you what is going on. I like the Zeitronix ZT2 which will data log AFR, rpm and more. The ZT3 is less expensive and will only log AFR which is not that much use on its own.

I have 45DCOE 152's. It has taken a lot of time to get the low end right but they have always worked well at the top. Do both pairs of carbs have the same type of floats and size of float valve?

Hunttheshunt has a lot of experience with modern Webers. He has posted that he spends time disassembling, cleaning up and rebuilding new ones before he uses them.
 

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Discussion Starter #7
A wideband AFR meter will tell you what is going on. I like the Zeitronix ZT2 which will data log AFR, rpm and more. The ZT3 is less expensive and will only log AFR which is not that much use on its own.

I have 45DCOE 152's. It has taken a lot of time to get the low end right but they have always worked well at the top. Do both pairs of carbs have the same type of floats and size of float valve?
same same. purchased new
 

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Richard Jemison has posted that it is possible to install the AV.s incorrectly which kills the top end.
 

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Is the bell crank and linkage identical? I had a problem when my Spider would only make 120 HP at the wheels and the linkage was snagging on the support rod and preventing the throttles from opening fully.
 

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Discussion Starter #11
Is the bell crank and linkage identical? I had a problem when my Spider would only make 120 HP at the wheels and the linkage was snagging on the support rod and preventing the throttles from opening fully.
I will double check
 
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