Measure the fuel pressure and volume from the pump. :) :)

See how many seconds it takes to fill a quart container,.................

jmz

If you blew through your carbs with compressed air you may have damaged your floats. I have seen this just recently, and the floats look like they were stepped on. It would be worth it to pull the tops off the carbs and check them all.

My $0.02....ignition

Plugs - replace (cheap)

Leads - Inspect them (using magnifying glass) for breakdown "exit wounds", and arcing to any nearby metalwork. Look very closely where the lead extends through the valve covers and down to the plug. At high combustion pressure, I've seen sparks jump sideways between the lead and head, rather than across the spark plug gap.

Engine runs fine without load (low air fuel mixture impedance), but is a dog on the road (high mixture impedance under load). Easier for the spark to make the leap to the head than across the plug gap.

...."borrow" a replacement set of known good leads and give them a go.

John

http://forums.pelicanparts.com/porsche-911-technical-forum/406747-what-happened-my-weber-floats.html

pope

Thanks for the link to the float pictures. This is exactly what I was talking about.