zenith Upgrade parts from MM

[nabilious]

If I'm not mistaken, emulsion tubes are essentially a small tube with the air correction jet screwed on top wish 12-13 preforations in it. I'd imagine the actual inside diameter of the tube is less important than the air correction screw size and the number/size of the preforations (I do have a spare set What thinks you about a couple more preforations or enlarging the existing ones slightly? Also do the #'s on the jet corresponde to the flow or the size (mm's)?
If i'm not mistaken some of the numbering is very different than a weber, which makes me ask that.
Thanks again,
Nabil

[john walker's workshop]

#s = jet bore. inside diameter, outside diameter, position of holes, size of holes, open bottom, closed bottom, all are important details of an emulsion tube. you can't randomly change these things without knowing what it affects. look at a weber emulsion tube chart for reference. they're all different, and none of the numbers are in order. like a F4 isn't even close to a F3. F3 is the normal performance weber tube, if you want to start there, but they relate to the weber body and who knows what relates to the zenith.

[azasadny]

Pierce Manifolds also carries carb parts and they are very knowledgeable...

[TVRLOTUSTR3]

This is what I have learned in three weeks of playing with Zeniths. I almost tossed them in the trash and put the webers on, but being a stubborn Swede I kept trying, and now I’m very happy with them.


1. Make sure all the emission or enrichment crap is blocked off. I spent over a week trying to tune them with all those tubes still hooked up. (bad idea)

2. Look out for a venturi spinning out of its location and blocking the main circuit. (broken clip) This happened to me on the way to VIR, I thought it was a fouled plug. Took me awhile to find it. Speaking of fouled plugs I have had a few.

3. Don’t take stock in the cheap OX meter. I have a K&N device that will read lean if you are to rich.

4. Look out for leaking or blocked accelerator jets, and point them so they don’t hit the butterfly.


This is what I have so far, the car runs strong, with no transition problems. (Smooth as silk)

32mm chokes

140 mains tried smaller, but would not pull at higher RPM. I think I will try to go a bit richer on the mains, I’m happy with the 140s the car pulls up to 7 real nice. 150 seamed to be a bit too rich, but the car was a rocket.

55 idle, screws turned out about 3 turns. I tried 60, 65, 70 all to rich (fouled plugs, bad transition burble)

Accelerator pumps come in just off idle. Tried adjustments all over the map with the richer idle jets. I did get it somewhat smooth, but kept fouling plugs, 55s were the ticket.

Stock Emulsion tubes


Engine: 2.4 with E cams

2.2 T pistons (exhaust pockets notched 2mm)

2.7S heads 35/35mm ports with some mild porting.

Heads machined for higher compression. I figure it’s about 9.5+ with the 2.2 pistons.

911L Dizzy, MSD, 34 total degrees

1 5/8 headers

NGK BP7ES plugs

[Mountaingoat]

Hello

Do you happen to have any main or air correction jets spare. I want to try to tweak
my Zeniths a bit. I'm after 220 or 230 Air correction jets and 110 or 115 Main jets??

Seem to have a real flat spot at 4500 and trying to smooth things out a tad.

Cheers

[TVRLOTUSTR3]

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