H4 twin SU rebuild

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970s
998 Cooper
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H4 twin SU rebuild

Post by 970s »

Hi, Just started to rebuild my twin H4 SU set, wonder if anyone remember should I soaked the floatbowl gasket in fluid before fitting? in gasoline or oil or what fluid ?.... should I change the medium bronze loat to a smaller diameter one? Like Swiftune kits used to do!
Thanks for advise!

Al ;)
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Re: H4 twin SU rebuild

Post by mk1 »

The gasket can be fitted dry, and although fitting the smaller float was a popular racing tweek a while ago, the standard float works better for road use.

M
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970s
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Re: H4 twin SU rebuild

Post by 970s »

:D Thanks Mark!
How's you Speedwell project goung?


Al
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Re: H4 twin SU rebuild

Post by mk1 »

You are welcome!

How's you Speedwell project going?

Not at all, I haven't touched it in about 3 years. I am however starting to think about doing it again. So, watch this space.

M
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Re: H4 twin SU rebuild

Post by johnsimister »

Re the floats, what are the pros and cons of the standard-size float versus the smaller one? Why is one better for racing and the other for road? I ask because my supercharged 850's H4 has the smaller float in a chamber able to take the bigger one, and I was wondering why this should be.

John
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Re: H4 twin SU rebuild

Post by rich@minispares.com »

john

it just means that there is an extra reserve of fuel in the float chamber 'on demand' if your really thrashing it
should you wish, you can contact me on rich@minispares.com

'long beard boss'
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Re: H4 twin SU rebuild

Post by johnsimister »

Thanks, that makes sense. Could be useful given the little beast's sometimes voracious thirst. I'll leave it as is.

John
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