Sidedraft Carb Questions

[Preyupy]

The 50f8 idles are way to big, every M10 engine I have ever done for the street (including mine with a 316 cam and 12.5:1 pistons) I use a 45f9 Idle jet. One other thing to look at is the carburetor casting where the idle mixture screw comes through (behind the throttle plate, its easier to see with the carb off the manifold) sometimes people tighten the mixture screw down so much it breaks the casting. If this has happened you will never get a good idle mixture.

[Inka’d02]

The 50f8 idles are way to big, every M10 engine I have ever done for the street (including mine with a 316 cam and 12.5:1 pistons) I use a 45f9 Idle jet. One other thing to look at is the carburetor casting where the idle mixture screw comes through (behind the throttle plate, its easier to see with the carb off the manifold) sometimes people tighten the mixture screw down so much it breaks the casting. If this has happened you will never get a good idle mixture.

I'll try that, thanks!

[jp02ti]

make sure the carbs are synced to each other as was said already. use an airflow tool like this one:

http://www.carburetion.com/weber/webermisc.asp

the first one is fine for us. this can make a HUGE difference in idle and performance. huge.