MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - What a difference carb needles can make.

Remember my post... "Can't get my MGA past 3000 RPM " and how I proudly proclaimed it to be fixed. Well, it just got worse and worse. I think I examined everything possible to make my car run better and nothing worked. fuel pump...clean the gas tank/ gas lines,timing...ignition...plug wires....coil....carbs...filters... you name it I checked it and nothing changed.

You will recall the carbs were professionally rebuilt and the rebuilder noted that my needles were "BB" which he said would run just a little leaner than normal. He's the professional so he should know ...RIGHT. Well out of desperation, I bought a new set of "GS" needles (the ones recommended for 1500 MGA) and installed them.

From the moment I turn the engine on I knew I had something fixed. I didn't even have to move the car. A quick idle adjustment...colour tuned the mixture and told my wife I was going for a test drive...around the block. Well thirty miles later at all over sixty MPH my little bazoo was flying. Running so well at speed that I had to watch myself , so that I did not get a ticket. What a thrill. Finally my car is normal.

So here is the question...how could such a minor part make such a big difference. I know there are hundreds of SU needles, for all different situations but my "BB" needles were supposed to be just a little leaner. The first three steps of both needles are all most the same and then come the change . The "GS" needles start letting more gas in and this solved my problem. How far off are "BB"nedles from "GS" nedles.

Gordon
Gordon Harrison

"feed" the needles in this link and you will see that the BB is leaner over the whole length from the word "go". So yur professional was right in that respect but it was too lean apparently. Congratulations on your succes; pure bliss isn't it?

http://www.mintylamb.co.uk/suneedle/
Willem van der Veer

A perfect demonstration of the difference between "professional" = one who charges people for advice or work; and "competent" = somebody who has a clue.

FRM
FR Millmore

As you found out, yes a small part can make a large difference. The differences in needles is in thousandths of an inch. You may have gotten it to run with the others if you had taken them down more flats, but you may have been rich at idle to get decient running at higher RPM's. Unless you have made specific modifications to the engine that would require changes in needles you will usually find that in most cases they run best with the original factory specified equipment.
John H

This thread was discussed on 19/06/2007

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.