Author Topic: Tripple weber set up  (Read 459 times)


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Tripple weber set up
« on: November 10, 2023, 16:59:20 »
Zephyr engine with triple weber carbs. Has anyone got the jet sizes as ours is running very rich.
Any help would be appreciated


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Re: Tripple weber set up
« Reply #1 on: November 10, 2023, 20:26:11 »
It would help if you confirmed some basic info. ( ie you don’t say if it’s idle,progression, main jet running that’s rich)
Your specific question is hard to answer with out more information  but I assume your engine is 2.6 litres six so 433cc per cylinder. If you don’t have a copy of Des Hammill Weber and delorto book get one - he recommends a 55 idle jet for a 500cc cylinder.

I assume the webbers are 45 dcoe?
You have balanced them?
What are the current idle jets, other jets ? ( ie 55F8?)
Despite a fixed idle jet the idle mixture ( air) still is variable  via screw with spring on each carb near intake manifold junction, best individually( each cylinder)  checked using something called a gunsons colourtune?
I have attached a photo.

If the basics don’t fix the issue or the jets are actually oversized for the cylinder volume I would start by looking at float heights and if any floats are perforated (Do a hot water test). Pinholed floats, and poorly functioning  needle shut off valves will cause rich running on idle. I am assuming here that your carbs have ethanol proof rubbers where required (ie needle valve tips).
Also the butterflys ought to be shut for the idle circuits to be the only ones operating.
The fuel delivery may also be an issue ( ie pump and regulator pressure-) as webbers are low pressure high volume carbs so to high a pressure will cause float needle seating issues.
« Last Edit: November 11, 2023, 10:12:27 by Flyinghorse »

James Eastwood

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Re: Tripple weber set up
« Reply #2 on: November 22, 2023, 18:00:47 »
Just my two penny worth, but I thought most of the Ford engines run 40 DCOEs.