SU carbs / manifold, what goes where?

[Healey Z]

I'm replacing the dual weber down draft set-up with some stock SU's in my '63 Healey with an L28 / 5 speed. I just received this box in the mail with most of the parts I need, and servicable SU's. Here is a picture of the car and a picture of the manifold/carbs. I have a lot of cleaning to do, before they find their way onto the car, but I would appreciate the feedback of the function of each opening and what is suppose to go there.

Edited May 19, 2011 by Healey Z

[LeonV]

Download the 1972 240Z FSM from xenons30.com. Take a look at the EC section, primarily Figure EC-3 on page EC-2.

BTW, #1 and #2 in your picture are the fuel inlets into the float bowl. They connect to the fuel rail. It also seems that you are missing the air cleaner, to which the float bowl vents and valve cover breather attach to.

Edited May 19, 2011 by LeonV

[Darrel]

3 is for the PCV

7 would attach to the stock z air box.

[Healey Z]

Thanks for the replies. I did look at the FSM and since I will not be using the airpump, can those items simply plug these items

1 Gas in

2

3 PCV tube in

4

5

6

7 vent tube to aircleaner

[Healey Z]

Also, how important is it to route cooling water through the intake?

[Patcon]

It depends how cold it gets where you are and whether the car is cold natured and if it will see cold weather at all. Plenty of people don't run heated manifolds. Also according to the Z therapy video you need to run some kind of air horn or you will lose a lot of power. The stock air cleaner evidently works as well as almost any other air horn or you could order after market air horns and filter them somehow. By the way that is a fabulous looking car, British car, British Green i believe, driving lights. Very nice...

Charles

[Arne]

For your purposes I'd plug everything on the balance tube except #3 (PCV) and the nipple for the vacuum booster, assuming that your Healy has power brakes. If not, plug that too. The PCV should connect to the crankcase vent tube sticking out below the distributor.

The threaded holes in the balance tube are British Standard Pipe, not metric or US pipe.

#1 & 2 are the fuel inlet. Fuel pressure should be in the 4-5 PSI range.

#6 are the float bowl vents/overflows. They would be connected to the airbox on a 240Z.

As noted above all SU-type carbs need smooth airflow for proper metering, so air horns are strongly recommended. On a Z, most people recommend sticking with the 240Z airbox which has decent horns built-in. But for your Healy, the Z airbox might look out of place, so if it were me I'd use a pair of medium-sized pod filters with third party horns inside.

For Sacramento weather I see no reason at all to plumb coolant to the manifolds.

[Healey Z]

Arne, you're the man. Thank you for the response, you really hit the questions right on the head, it is appreciated. I don't think I will have clearance for the stock aircleaner box, so I will look for some horns. Where does the disti draw it's vacuum from? No power brakes on the car, it is as raw as it gets, it does however have the factory disc brakes up front and stops reasonably well.

The Z motor swap was done about 25 years ago, as far as I can gather from the box of receipts I have. It has been a fun project and installing the SU's should get it back on the road.

Here is a picture back from paint, with no engine/trans.

[Arne]

Where does the disti draw it's vacuum from?

There should be a small barbed brass nipple on the front carb body. Looking down on the carb, it should be at about 10 or 11 o'clock. See below.

[Healey Z]

Arne, WOW, that engine compartment is incredible! I will look for that port for the vac advance. Thanks.

I was able to sneak out at lunch and go look at a '73 Z running without a smog pump. Basically, EVERYTHING was plugged off. I can't say it was that attractive looking, but it made things pretty clear: strip the part down and plug everything except for the PCV inlet.

1 Gas in

2 Gas in

3 PCV tube in

4 plug

5 plug

6 plug

7 vent tube to aircleaner

8-10 plug

Edited May 19, 2011 by Healey Z

[Patcon]

European balance tubes are available. I believe Z therapy has them or something very similar if you want a cleaner look

Charles

[Healey Z]

Charles,

I went on Z Therapy's web site and saw what you were talking about: very nice.

ZT128 Euro-Style Balance Tube Polished and Plated, All extra holes are Welded Shut, Ground down smooth and polished $160.00 + core

If I can pick up an extra one, this may need to be a future project for me.