3.8 carbs - which options do I have?

Technical advice Q&A
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Sepp
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Joined: Sat Feb 19, 2022 9:04 am
Location: Munich
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#1 3.8 carbs - which options do I have?

Post by Sepp » Sat Feb 19, 2022 9:19 am

Dear community
I am Sepp, live near Munich in Bavaria and I try to bring a 3.8 FHC back on the road with all the ups and downs.
An original nicely refurbed 3.8 engine replaced a broken and not to spec 4.2.
Obviously, the 4.2 manifolds won‘t fit and I am in need of an inlet solution.
I am open to any solution, Webers included.
Will Mk X carbs and their manifold fit (choke issue is a different story) and what would be the potential drawbacks?
Cannot find suitable 3.8 manifolds for Weber, do they really exist? Webcon pretends to have them, but their pictures tell a different story.

Thank for any helping hand or parts offered.
take care
Sepp
3.8 FHC 62 RHD 860435 R8842-9 carmen bisquit, in need of a lot of attention
4.2 2+2 S1 67 carmen black LHD, daily driver, full S1 except camshaft covers

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mgcjag
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#2 Re: 3.8 carbs - which options do I have?

Post by mgcjag » Sat Feb 19, 2022 9:23 am

Hi Sepp...welcom to the forum......one of our members had a set for sale here...check it out viewtopic.php?f=7&t=18464&p=149742&hili ... bs#p149742
Steve
69 S2 2+2 (sold) ..Realm C type replica, 1960 xk150fhc

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christopher storey
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#3 Re: 3.8 carbs - which options do I have?

Post by christopher storey » Sat Feb 19, 2022 10:29 am

To answer one of your questions : No, mark 10 carburetters cannot be used , and nor can the manifolds , as the mark 10 design mounts the carbretters higher than the E type manifold design, and in addition the carburetter bells are taller than those on the E type . In addition, the mark 10 has the additional starting carburetter rather than manual chokes

What I am slightly puzzled about is your statement that you cannot use the 4.2 E type manifold on a 3.8 litre engine. Assuming that this 3.8 is a straight port head, my own view is that the manifold should fit, although it may be necessary to blank off any redundant water passage holes . Perhaps others would like to comment on this

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Sepp
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Location: Munich
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#4 Re: 3.8 carbs - which options do I have?

Post by Sepp » Sat Feb 19, 2022 2:04 pm

What I am slightly puzzled about is your statement that you cannot use the 4.2 E type manifold on a 3.8 litre engine. Assuming that this 3.8 is a straight port head, my own view is that the manifold should fit, although it may be necessary to blank off any redundant water passage holes . Perhaps others would like to comment on this

Hi Christopher
thank you for clarifying that clearance would be the main issue with Mk10 carbs.
I hesitate to install the 4.2 manifold with blinded water passage holes as the remaining rectangular holes in the manifold are considerably smaller than the corresponding holes in the cylinder head and I fear heating issues. The head is a 3.8 e-type head (they are all straight port, aren‘t they?).
3.8 FHC 62 RHD 860435 R8842-9 carmen bisquit, in need of a lot of attention
4.2 2+2 S1 67 carmen black LHD, daily driver, full S1 except camshaft covers

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christopher storey
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#5 Re: 3.8 carbs - which options do I have?

Post by christopher storey » Sat Feb 19, 2022 5:57 pm

All E type and Mark 10 heads are straight port, but all other 3.8 heads ( Mark 2 and Mark IX) are B type heads

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PeterCrespin
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#6 Re: 3.8 carbs - which options do I have?

Post by PeterCrespin » Sun Feb 27, 2022 2:36 am

Sepp wrote:
Sat Feb 19, 2022 9:19 am

Cannot find suitable 3.8 manifolds for Weber, do they really exist? Webcon pretends to have them, but their pictures tell a different story.

Thank for any helping hand or parts offered.
take care
Sepp
I have what you need.
1E75339 UberLynx D-Type; 1R27190 70 FHC; 1E78478; 2001 Vanden Plas

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