[Ennio]

Hello, I am going to buy a synchromter for tuning my carbs (Dellorto DHLA 40) and found a very good one on ebay, EMPI brand. It comes with all the hardware needed (adapters and stuff). You may have a look here

http://cgi.ebay.com/ebaymotors/ws/e...=ADME:X:AAQ:US:11&viewitem=&item=150146936531

I have a question regarding this tool. I`ve seen synchrometers that read up to 40 Kg/h and others that read up to 30 Kg/h. This EMPI reads up to 30 KG/h. Would it be fine dor tuning this carbs on a 2l engine? I am going to buy it for my mechanic who works on other alfas too (mainly boxered Alfas) and if I like it I would buy one for me.

Thanks in advance.

 

[Richard2]

I bought the older style Unisyn off eBay. It was a total waste. Very poorly constructed and unusable. I ended up making a manometer using a yard stick, and clear plastic tubing that worked really well.

 

[Ennio]

Edelbrock sells a Uni-Syn for 15 bucks on Summit Racing.Should work since their pruducts are very good indeed.

 

[Cosmo]

I splashed out and bought one of these.

You can monitor all 4 venturis at the same time, without even having to take the air filter off. Pinpointed two vacuum leaks very quickly and got the carbs balanced in a couple of minutes.

 

[Ennio]

Yes Carbtune seems great but at a cost of us$120 to be used once in a while, I think it is not worth for me now!!! I still have to paint the car and buy new tyres, so right now I am searching for something that will make the job and is cheaper. Thanks.

With Carbtune and colortune you can have the carbs set up very very quickly!!

 

[Cosmo]

How much is your time worth? The money was well worth it for me. I had spent hours trying to get it balanced without knowing that a couple of slight vacuum leaks were the problem. Also, better tuning (and less fuel spent while swearing at an idling engine) is more economical so I may get my money back in the end.

Yes, I have a Colortune as well and it was very quick work to get a good idle, even down to 500 rpm. The mechanic I take my cars to for MOTs even remarked on how smooth the idle was. If you have plenty of time to spend on an afternoon fiddling with carb adjustments then that's OK but I'd rather be out driving.

 

[Ennio]

If I lived in the States and wouldn`t have to pay the shipping to Peru, including sales taxes here (19%) and tariffs (13%), I would take it right away since it is the same device Alfa shops used. You lucky guys!! But for the time being I can`t, I will use the other type of synchrometer and take a little longer but try to get it the best I can.

 

[Cosmo]

Now I can see that would be expensive for you It is mostly used these days for motorcycle tuning - have you tried checking at local motorcycle places to see if they could sell or even lend you one?

 

[Ennio]

Thanks for the tip, I`ll try to get/use one asking these guys. But I think that with the "one barrel at a time" synchrometer and an exhaust fume analyzer (a friend knows a place where we can use it ) I`ll get the carbs right. Right now the car is okay, but when I had the fumes analyzed the CO was high as well as unburnt hydrocarbons, I now realize that after I had the carbs tuned I changed the exhaust completely (now it has a 2 inch diameter tube) and that may have affected the carbs...As you say, I am wasting fuel and money right now, but it soon be corrected

 

[Giorgio68]

Cosmo,

Where did you buy the synchronizer. Could you send me the product info.
I guess anyyone can use this without any problem, since I am not that familiar with carbs.
I installed 2 sidedraft 40DCOE Webers with a friends help, now I hear some vacuum leak on one carb, so next thing I will replace the soft mounts.

Giorgio

 

[Ennio]

All the info you need on the Carbtune is here: Morgan Carbtune - carburetor synchronizer for balancing motorcycle carbs
It includes its price in UK pounds including shipping, also the relevant info on the colortune (I am trying to buy a very good used one of ebay since it seems to be the tool needed for the job).

 

[Richard2]

When I was having all the trouble with my carbs, I bought ColorTune and was very happy with the results. However, first I balanced the carbs using a home made manometer. It also worked well, but needed some care in starting the car and idle speed so the water in the manometer didn't get sucked into the carbs. I used water instead of oil, because water is easier to work with and heaver than oil. It gives a better range than oil. Mercury of course has is hazardous drawbacks.

 

[Cosmo]

Cosmo,

Where did you buy the synchronizer. Could you send me the product info.

Ennio has posted the link for the manufacturer, it is probably available through distributors as well.

I guess anyyone can use this without any problem, since I am not that familiar with carbs.
I installed 2 sidedraft 40DCOE Webers with a friends help, now I hear some vacuum leak on one carb, so next thing I will replace the soft mounts.

You can somethimes confirm that it is the soft mounts by flexing the carbs up and down. This will open and close any cracks in the mounts and the engine revs will change. By inspection, mine looked pretty bad but passed the above test. When dismantled I found that the actual problem was that the mounts had been fitted without gaskets!

The carbtune is very easy to use - I needed to run it upside down (see the instructions) to get the correct range. Along with a colortune, you'll be able to find all the problems and get a very good idle.

 

[alfaparticle]

Cosmo:
I would like to see a closeup picture of the adapter where the vacuum hose connects to the carb. I have a pair of Dwyer Magnehelic differential pressure gauges that I would like to adapt for synching Webers.
Thanks,
Ed Prytherch

 

[Giorgio68]

Cosmo,

Have you used the colortune? I will be needing the size of the plug on my Alfa, they are suggesting 14mm, I just want to double check if it is 14mm before I place an order from Morgan carbtune.
I can't find the size of the plug on the websites of NGk or champion, the only thing I found is the plug but no info on the size.

Giorgio

 

[Ennio]

If you use NGK, and your plug has the B code then you have a 14mm plug. I have "BR7EIX Iridium IX plugs from NGK" and e-mailed Morgan and they confirmed this to me.

If you want a double check you can e-mail Morgan or any spark plug manufacturer to be 100% sure.

 

[Giorgio68]

I tried the carbtune today, but can't seem to balance the carbs bar 2-3 are off and they are not stable. how can you pinpoint and check vacuum leaks. It says in the manual to make sure not to have any air in the carbtune, how can you check that.

Giorgio

I splashed out and bought one of these.

You can monitor all 4 venturis at the same time, without even having to take the air filter off. Pinpointed two vacuum leaks very quickly and got the carbs balanced in a couple of minutes.

 

[Cosmo]

I tried the carbtune today, but can't seem to balance the carbs bar 2-3 are off and they are not stable. how can you pinpoint and check vacuum leaks.

Get a spray can of carb cleaner, preferably with a straw attachment for directing the jet, and spray it at various places where you think there could be a leak - the gasket areas, the rubber mounts, the take-off for the brake booster etc. If there is a leak the engine note will change as the mixture changes. Some people says WD40 works as well but I've found the effect to be more pronounced with carb cleaner.

It says in the manual to make sure not to have any air in the carbtune, how can you check that.

I'm not sure, it wasn't an issue for me. I did have the same sort of problem as you with being unable to get the balance set accurately with any kind of air leak.

 

[wolf]

i use a system with 4 dials that is used to synchro/tune motorcycle carbs. all venturis can be checked at the same time.

 

[Giorgio68]

Cosmo,

The Solex C40 ADDHE on my Super has screws for each venturi for balancing, then the screws for air/fuel mixture. The webers on my Berlina 40 DCOE doesn't have the screws for each venturis, I don't understand how can you balance them without these adjustement screws. The only thing it has air/fuel mixture plus the fitting for the carbtune. How did you balance your webers without these screws?

Giorgio