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MG MGB Technical - Jetting a weber downdraft

What I am looking to do is pull a little more power without comprimising too much economy. I like that I can run down the road running off the first barrel and get good mileage, but when I put my foot into I would like more power. Has anyone played with putting a larger jet in the second barrel so when you stomp it you have a little more "omph"? Does this cause hesitation or other problems when the second barrel opens?
Thanks.
Bryan

I would really try to see if you can get the linkage to make both barrells open at the same time. That would be the quickest and the cheapest and the easiest way and not a headache. You have to look at it compared to running a zenith with a 1 3/4"s and two 1 1/2" su's sucking in the fuel air mixture compared to your single barrel progressive throttle.
James

Not a bad idea. I dont know I would want both open all the time, I do like being able to really knock down good mileage with the single barrell. But if I adjust the linkage to open sooner, that would give me more of the second barrell to play with. I will definately play with that linkage before rejetting.
Thanks!!
Bryan

Bryan,

Before you start be sure the second barrel is opening. I thought my Weber was a little weak and while I had my daughter floor it (motor off) I noticed that the cable had stretched and the second barrel wasn't opening at all. I adjusted the cable and now can feel the difference.
Luis

Installing a larger jet with out changing the choke size will only make the engine run rich. For a larger fuel jet you need more air to keep the proper ratio of fuel to air.
John H

http://www.webercarburetors.com/

http://www.redlineweber.com/

Try contacting either of these two companies for the desired linkage

I also have a weber downdraft w/manifold I am looking to sell with really no time on it whatsoever, it was just on the car (New) and run a hand full of times to coat the engine with oil. So on the outside it does not look as new as it should be. I guess I should put this in the classifieds
James

This thread was discussed between 11/06/2007 and 12/06/2007

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