Zetec jetting

[Sandy]

Am running a 2 litre Zetec installation with twin 45 webbers.

 

Could anyone advise what the optimum or standard jet sizes should be?

 

OK, thanks for the help. Have got info from both Raceline and JW with regard to jet sizes.

 

Problem now is checking my MBE ECU Can anyone help? (Cos MBE cant!)

 

2L Zetec Classic green with yellow nose band

 

Edited by - Sandy on 22 Apr 2004 10:42:38

[Doug]

It might be worth your speaking to Peter McEwan at Raceline, near Guildford. They built my 2.0 ltr Zetec (fuel injected) but I would have thought they will be able to help since they do, from memory, build carb engines too. their website is worth a look too: www.raceline.co.uk

 

Peter is a very approachable and helpful guy and you'll get him on 01483 811978 / 810812.

 

Best of luck.

 

'Have you any idea what it's like to have the wind rushing through your hair!'

[millsn]

155 F16 with the bit at the end of the jet being a '130' can't seem to find the idles at the mo

 

 

Nigel Mills - 2.0 Zetec carbs soon to be EFi'd

 

Edited by - millsn on 20 Apr 2004 22:12:38

[Delberts Wallet]

Sandy

 

2L Zetec Classic green with yellow nose band

 

should read "yellow nose band in need of number plate"

 

Blue and Carbon 6 Speed Supersport

Picture of my car NOT doing donuts here

[Castrol]

Gareth,

 

Rumour has it that there is now a number plate attached 😳

 

Matt.

[Sandy]

Yes thank you Gareth. I now have a number plate!

 

Is there anyone out there that is running an MBE ECU on a 2l Zetec carbs?

 

Or, anyone who knows where I can get my unit checked for faults and the mapping checked?

 

MBE themselves dont seem to be much help

 

2L Zetec Classic green with yellow nose band

[Slomove]

here is my spec after a few optimization steps. It si for a 2.0l Zetec ZX1:

- 45DCOE152, running on 2.5 psi fuel pressure. Floats are adjusted to 12.5mm

- 36 mm chokes

- I had 55F9 idle jets, tried 60F9 which idled more smoothly but too rich on the mid-range and went back to 55F9

- I had 135 main jets and changed to 145

- I did not change the emulsion tubes and don't know what I have. I read in various recommendations that the emulsion tubes change is something for the real insider. There are no recipes for how to change.

- I had 185 air correction on the 135 main jets and it did not work well with the 145 main jets. I drilled them up with a 1.95mm drill bit so they are probably close to a real 195 air correction

- The carbs came with 3 transition holes and I added a 4th hole, see here:

http://home.earthlink.net/~slomove/sitebuildercontent/sitebuilderpictures/4thprogressionhole.jpg

That made a big difference in light throttle drivability but I think I can still increase the 4 th hole or maybe even add a 5th hole. At minimal cruising throttle (barely opened to maybe 1 mm) the AFR increases to 18-20 and the exhaust begins to pop and bang.

- The idle mixture was preset to 2.5 turns from stop and then fine tuned simultaneously to give an idle AFR of 12-13 @1000rpm.

- I use a carbtune balancer (vacuum based motorcycle balancer) and mounted nipples in the manifold to tap the manifold pressure for all 4 cylinders. It shows all cylinders at the same time. I also plugged the connecting channels in the Ford manifold gasket (not sure if that is necessary or even a good idea).

- I had a 45 pump jet, tried a 35 jet and went back to 45

- I have not dyno-optimized the ignition map yet. I am using a blend of various maps (mainly from a map picture taken from Emerald's web site but with less advance as safety reserve). Feels good but I don't really know how much I am giving away.

- driving quite well with 20-27 mpg on the road and good throttle response. Track consumption is, well, ....

- Engine starts with the first key turn, needs however some pedal pumping and nursing when very cold. I disconnected the cold start choke mechanism because it never worked and it is not needed.

 

 

Edited by - Slomove on 22 Apr 2004 01:17:37

[philwaters]

Hi,

When I initially set my car up I had a huge flatspot at around the progression area (2750-3k rpm). Once run in I took it to a local RR and the first thing they changed was the emulsion tube from the F16 through a couple of sizes to an F7. This improved things no end and then they sorted out the rest...

I ended up with the following:

 

36mm Chokes,

135 Main jet

155 Air jet

40 Spill Valve,

55F9 Idle

F7 Emulsion Tube

50 Pump jet

 

All of that is for a 40DCOE mind.

 

Phil Waters

 

Edited by - philwaters on 22 Apr 2004 08:56:05