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Balancing ITB's
se7ensport - 5/5/12 at 07:08 PM

I have an airflow meter, but getting it in a position that I can read and change the balance screws is a real challenge. So I was thinking about taking the manifold off and balancing them on the kitchen table using a vacuum cleaner to provide a constant flow. Any reason this wouldn't work well?

lsdweb - 5/5/12 at 08:10 PM

quote:

Any reason this wouldn't work well?


I think that if you add the word 'wife' to 'kitchen table' and 'vacuum cleaner' you may find a reason why it won't work!

Not very helpful I know!

Wyn

Toltec - 5/5/12 at 08:19 PM

quote:
Originally posted by lsdweb
quote:

Any reason this wouldn't work well?


I think that if you add the word 'wife' to 'kitchen table' and 'vacuum cleaner' you may find a reason why it won't work!

Not very helpful I know!

Wyn




and take another from Mrs Toltec

se7ensport - 5/5/12 at 08:46 PM

Fortunatley my wife is used to this by now, de-gunking a sump in the bath when we first got together pretty much set her expectations!

austin man - 5/5/12 at 08:48 PM

could I share your wife please, putting overalls on in my house is a no no lol

pjay - 5/5/12 at 08:49 PM

Love the responses!

Is it possible to remove the trumpets instead (just thinking that would be less hassle than remove the inlet)?

se7ensport - 5/5/12 at 09:07 PM

Incredibly it's less hassle getting the whole set-up off v's taking the trumpets off, also due to the wings I can't see the guage without looking through the wheel arch.

Strontium Dog - 5/5/12 at 11:18 PM

Have you got something you have to hold over the inlet? If so, bin it and make yourself a decent manometer out of aquarium pipe, some aquarium valves a few T's and a bit of ply. You can then plug into the ports on the tb's and see all four at once. Google diy manometer or diy carb balancer. There's loads of links and you'll soon get the idea. Very locost and completely accurate!

whitestu - 6/5/12 at 08:29 AM

Do the ITBs have a vacuum take off?

If so invest in a Morantune balancer. The cost a few quid but work brilliantly.

Stu

se7ensport - 6/5/12 at 08:51 AM

Yes my TB's have a vacuum take off and borrowing a inlet gauge, making a manometer looks pretty simple which I'll do to get it set quickly today and order a proper one on Tuesday. The Morgan Carbtune Pro seems to get the best reviews and isn't going to break the bank for the convenience that it provides.

Strontium Dog - 6/5/12 at 10:05 AM

Once you've made a manometer I doubt you'll want to waste your money on a set of gauges that'll be no more accurate. In fact, if the particular Bourdon gauges used aren't well matched to each other they could be less accurate than a diy one. The level of the fluid in the tubes does not lie! I have balanced many carbs and a few TB's like this over the years and it really is one of those things were the simplest thing works best.

A Bourdan gauge is merely a coiled tube that tries to straighten out under pressure/vacuum which in turn swings a needle. Water, or even better in this case alcohol (I use methanol with a little food coloring in it) levels are accurate to the curvature of the earth so pretty hard to beat!

To help you you usually need to balance the tb's as two pairs, left pair and right pair, then balance the two pairs together. Don't skimp by not fitting the aquarium valves or you could suck the fluid out of one of the tubes if your tb's are very unbalanced. Start with all four valves closed and open them just enough that they start to effect the fluid levels and your away!

Don't forget to keep checking your tick over as it will change as you set the tb's.

[Edited on 6/5/12 by Strontium Dog]