Weber Mains Help Needed

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71rocket
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Weber Mains Help Needed

Post by 71rocket » Wed Jul 20, 2016 6:21 am

Twin 45dcoe on 5ltr V8.........need advice with rich high rpm accelerating(5000+) The motor has great top end with as small as 145 mains but is starved of fuel at lower rpm.At low rpm it pulls hard with 185 mains but soots plugs and heaps of grey fume from tail pipes at high r
I've experimented with Air Correctors and Etubes but both seem to just make it leaner or richer through out the rev range ie; larger AC reduces low down accel like smaller main would.
I've tried F15 F2 and F8 etubes but seems only tube diameter makes a difference.
Q.How can I get rich low end but lean out up top?

Geoff2
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Re: Weber Mains Help Needed

Post by Geoff2 » Thu Jul 21, 2016 5:16 am

On the DCOE, the acc pump supplies fuel at high rpm. You could try reducing the nozzle size. Other things you could try: a larger air corrector jet because the AC jet has the most influence at higher rpms. Try drilling two 1mm holes in the E tubes, inline with the current highest holes. F8 is a rich tube as it only has two upper holes. F2 would be a good tube to try, it has many upper holes.

71rocket
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Re: Weber Mains Help Needed

Post by 71rocket » Fri Jul 22, 2016 4:27 am

I am using 50 pump jet where as the Redline info I have suggests a 40,thanks Ill try that.

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modok
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Re: Weber Mains Help Needed

Post by modok » Thu Sep 08, 2016 11:26 pm

I'll discuss jets and e-tubes anytime, but sorry I don't think it will do much good. if this is two carbs bolted to an adapter bolted to a manifold then It is acting as expected.
If it were possible to make it run far richer at low rpms I do not think it would solve your sparkplugs being black, it would still not work right.


If I have guessed wrong I am sorry, but please do explain how you run 8 cylinders with two dcoe?
Glen Urban

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