Ferrari Forums banner

Final word on 78 308 carb float heights

1754 Views 4 Replies 0 Participants Last post by  JRV
G
I've done a lot of researc

I've done a lot of research regarding float heights on 308 carbs and just wanted to see if there was an expert consensus.

78 308 owners manual indicates float heights at 48mm to 58.5mm (a 10.5mm swing between open and closed).

Is there a valid reason to set the float heights higher, to say 46mm?
1 - 5 of 5 Posts
G
Hi Mike,

Float level actual


Hi Mike,

Float level actually plays an important part in carb tuning. If the floats are set to high the engine can run to rich across the entire rpm range. I have always set 308 floats between 48-49 and exactly the same on all carbs with very satifactory results.

I can see no reason to set the floats higher or lower.

Regards, JRV
G
Thanks, JRV. One last question

Thanks, JRV. One last question. I've read some debate as to whether or not you measure the float heights against the main base of the float, or the 1mm-higher "soldered on" ridge of the float... I'm currently measuring against the smoother, "true" part of the float.
G
Mike,

I measure against the


Mike,

I measure against the bottom float corner or flat plane rather than the soldered ridge, without gaskit. While you're setting the floats also make sure they swivel striaght up and down (not crooked) and that the tab that rides on the needle is making a nice square contact.

Regards, JRV
G
BTW:

while the tops are sti


BTW:

while the tops are still off and once the bodies are assembled, fill with fuel and check carefully for no internal fuel leaks and that both injection nozzles work the same by cranking the throttle shaft multiples of times and inspecting the operations. Internal leaks of many of the port plugs is common and can lead to difficulty setting idle mixture if droplets of fuel are leaking into the throats via any of the internal passage plugs.

Regards, JRV
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top