Carb tuning question

[Mudhen]

Now that my '65 is sort of running I'm trying to dial it in.  One thing I've noticed is that I just can't seem to get the mixture to richen up enough.  I'd really like to make it too rich so I can see the difference on the plugs and then back it off - but no deals.  I'm pretty much all the way out on the adjuster and the plugs are still totally white.

It has twin 1.25" SUs that I bought brand new back around 2000 so assume the needle is some standard one.  My car is 1275 .060 over, stock cam, specially bent lcb header that leaks all over the place/PlayMini exhaust.

I was looking at the AH2 'rich' needle at Seven...and then looked at this chart from MiniMania:

http://www.minimania.com/Needle_codes_for_SU_carbs

Maybe a 'BDL'?

Anything else I should be looking at before going down the needle route?  The car has sat for 3 years or so, so no possible issue is off the table at this point.  And I've never bothered really trying to learn how to tune the thing - just always happy that it was able to go down the road at all on the rare occasions when it did!

Thanks guys!

Pat

[ADRay]

 77.gif

[Mudhen]

77.gif

Have you taken yours to a body shop yet?

Don't worry, I won't tell anyone some idiot backed in to your poor Mini...

[ADRay]

no secret

http://www.restorationmini.com/forum/index.php?topic=759.0

[jedduh01]

Simple try -  Check the needles in the dashpot - Loosen setscrew  and see if the needle will go up into the dashpot any further.   

Reason :  I had a full Rich condition on my car - cause the needle was up high in the dashpot--- that got  kept the needle leaner than it could have been based on the taper.
Shift the needle down to FLUSH with the dashpot and it leaned my mixture out more.

Easy try before needles.
But if you say you have dropped the jets as much as possible - or ALOT- this probably will not richen the mixture.

- Double check = spray around your manifolds for air leaks- Excess air leak will contiue to give you a LEAN conditoin (too much air - not enough fuel.

[Mudhen]

Awesome - thanks Jedduh!

Are the needles supposed to 'float'?  My old carbs the needles were fixed solid - wicked pain making sure the jet was centered and the plunger would fall freely.  But on these the needle moves around.  Really nice not having to center them, but is that they way they're supposed to be?

[Tim]

Yes.  Some of the carbs came with floating needles.  I'm pretty sure it's the older ones that came floating and then later they switched to fixed, but I'm no expert.

I have the same carbs as you, and they are a bit of a pain to set up - but they look the business under the hood.

Have you tried balancing them with an S.U. tuning kit?  (http://www.minimania.com/part/00-3683/Su-Carb-Tool-Kit)  This is a good place to start and then follow that up with getting the mixture accurate.

Tim.