Using vacuum gauge on a twincam

[nitch]

I would like to do some tuning on my 2 Delleortos using a vacuum gauge.
As I unterstood from this thread: http://www.lotuselan.net/forums/viewtopic.php?t=5292

Won't work on a Twink because there is no plenum for all 4 cylinders,you are reading the
vacuum for 1 intake valve and the reading is what you saw.

Should I use 4 vacuum gauges of perhaps use the same one serialy?
Thank you,
Liad

[worzel]

Hi Liad

Just use the same one on each cyl. You'll need some sort of restrictor in the tubing to steady the needle.

Alternatively- BurtonPower do a nice airflow guage for around ?50 that is very sensitive to airflow and quick to use.

John

[alaric]

I bought a four column manometer from ebay that works really nicely! It's made by Carbtune, and I bought it from Eurocarb ltd.

It's supplied with 4 rubber tubes and adaptors that screw into the barrel of the carb on the vacuum side - at least they did on the Dellortos on my engine. The ad says it fits DCOE also.

Tuning the airflow took seconds once it was hooked up. The engine ran beautifully afterwards.

They also sell a two column manometer, and a vacuum guage that fits into the trumpet at the inlet to the carb. Personally I prefer the one that I have 'cause I don't have to take the airbox off or disturb anything else; just have to remove a little screw from each barrel and screw in the adaptors.

It was ?50.

Sean.

[twincamman]

i use a unysin ---works well as you are measuring the flow to balance the both carbs ----used it for years ---works on both my twincams --in spite of all the 'experts' opinions ---or you can listen to individual sucking sound through a rubber tube ----[killing a chicken and reading its entrails also works according to some experts ] ----ed

[cliveyboy]

I am with Sean on this one
I also use the carbtune 4 column manometer and its great.
The big advantages are it is so quick to connect up, and as you plug straight into the carbs you do not remove the airbox.
Its got to be the best method as you set up the carbs as a complete working system under load i.e pulling air through the air filter and air box.

Clive

[nitch]

Where exacly do you plug the gauges?
I would appreciate a picture or a diagram.
Thank You,
Liad

[alaric]

I've put a couple of piccys into user galleries > alaric > rebuild.

[nitch]

Thank you!
It's just where I suspected it would be after looking at the diagram at eurocarb's site.