MGA Part Numbers - AUC8170 Needle and seat assembly, Carburetors

The MGA With An Attitude

MGAguru.com

MGA Part Numbers - AUC8170
AUC8170 Needle and Seat Assembly, Carburetors

PART NO.  SPL.PAGE  DESCRIPTION                                                           
AUC8170   15.D.5    Needle and seat assembly (2) -(float valve, carburetors, 1500)
AUC8170   15.D.6    Needle and seat assembly (2) -(float valve, carburetors, 1600)
AUC8170   TC.D.4    Needle and seat assembly (2) -(carburetors, Twin Cam)

Originally all MGA (including Twin Cam) used the same part number AUC8170 for the float jets. There have been may variations over the years.
-- Solid brass pin.
-- Brass pin with rubber tip.
-- Brass pin with spring loaded tail pin.
-- Brass pin with both rubber tip and spring loaded tail pin.
-- Slight variations in the spring loaded tail pins.
-- Grose Jets (real ones) with two small internal balls.

Some aftermarket numbers:
VZX 1101 - Needle & Seat from Burlen
WZX1100A - Needle & Seat (plus a cover c=gasket).
WZX1101A - (might be a newer BMC number, or a kit with multiple cover gaskets).
371-061 - Needle and Seat Kit - Moss Motors USA (Viton tip, solid tail, photo above left)
386-390 - Grose type jet - Moss Motors USA - (Photos below)

Joe Curto was commenting about the different seat diameters:
"As far as I know there are not differences in H4/H6 float needle and seats, usual SU hole sizes is around .096 and .070 I believe there was also a smaller than .70 as fitted to Bugeyes but we use the ..096 in everything".

Pictures at right are Grose Jets, or "Grose Type Jets", identified by the radial exit holes and ball at the bottom end. The Grose Jet is a patented device, as well as a registered trade name. With patent now expired, anyone can manufacture and sell these parts royalty free, but if not paying the royalty, then the name "Gross Jet" should not be used. Ergo the alternate name "Grose Type Jet". Unfortunately lots of these parts are advertised and sold as Grose Jets, even when reproduced with inferior quality. Original Grose Jets were made in England. If the parts are made anywhere else, they are not genuine Grose Jets, and many of the knock-offs have inferior quality and functional problems.