How To Tune Your Carb

Anonymous · Post by **Anonymous** » Fri Jan 14, 05 1:54 am

aah, maybe i didnt need a new carb, sounds like mine had a burst power valve. float levels were always ok but it flooded bad, although, strange thing was it was intermittent

oh well, new carb is on but bogs at about 1/4 throttle. hugh has left me a pile of jets to play with, when i am brave enough to have a go at it

Post by **MattH** » Fri Jan 28, 05 8:45 pm

Ive finally got the hemi six charger running today without stalling.
Question now is, should I have vacuum at idle?
I cannot find a take off port above the throttle butterflies, so the vac is off the intake manifold.
The carb is a 2 barrel manual choke Holley, not sure on size but came off a 360. There is plenty of vac, but it seems to rev slightly better with no vac connected. still splutters just off idle.
Havent managed to get it running cleanly yet, but early days. Just need to know about the vac for now!

Alex · Post by **Alex** » Fri Jan 28, 05 9:23 pm

You should have vac at idle, below the throttle blades, there should be no vac at the dizzy at idle though if that makes sense ! there should be a spark port on the carb to pic up the dizzy tube..

Post by **MattH** » Sat Jan 29, 05 7:29 am

I cant find a spark port, only thing remotely similar is a tube coming off the side of the jet block about 2/3rds of the way up. I Thought it was just a fuel bowl vent , and when you blow through it I can hear the air in the inlet throats high up. Could this be it??

Trouble is Ive grown up on 150 Strombergs and SU carbs which are somewhat different (I will get to the slowest/most embarrasing thread soon!!).

Alex · Post by **Alex** » Sat Jan 29, 05 8:55 am

It may be? take a pic of the carb and stick it on here and we will tell ya, or stick a vac guage on the port, it should read 0 at idle and pick up as you open the throttle.

Dave-R · Post by **Dave-R** » Sat Jan 29, 05 12:22 pm

Yeah that is the correct port Matt. Side of the metering block above one idle mixture screw.