Custom built intake manifolds for Herald engines

[Eric Smith]

Hi Guys

I am looking for help again - my Standard 8 was retro fitted with the 1147cc Herald engine (1960/61) - I want to give the car better carburettors and performance - the obvious way would be to replace the Herald downdraft/exhaust manifold with Spitfire manifolds and carburettors.

A problem has now become obvious since looking at the cars engine bay, my car does not have the same amount of room the Herald/Spitfire has, in that the rear carburettor of twin Spitfire carburettor’s and linkages may be very close or even hit to the cars break and clutch master cylinders.

There are two things I need to know, firstly I need to know how wide two Spitfire carburettors and linkages are? Secondly I need to know the distance from manifold gasket to outside of a filter box or filter case. Could a nice Spitfire owner be extremely helpful and let me have some dimensions?

If I have to ditch the idea of twin carburettor’s - does anyone know if there are replacement manifolds or modified manifolds available so I can fit something like a Twin Choke Webber carburettor.

Lastly - if there are no custom manifolds to buy do any of you know of anyone who can I talk to get a manifold adapted.

Thanks guys - sorry to take up more of your time, your help is much appreciated!
 

Eric

 

[DanMi]

OK from the US but shows weber can be done  https://www.ebay.co.uk/itm/273037916435. I have also heard of people using Mikuni motorcycle carbs

Edited November 19, 2023 by DanMi

[JumpingFrog]

Eric, you can also consider modifying the pedal boxes, lots of information on the Standard Motor Club forum:
https://standardclub.proboards.com/thread/2180/spitfire-pedal-box-conversion

I also saw someone who is planning to produce single SU carburettor manifolds for the 6-port heads, he posted on Facebook a while back:

https://www.facebook.com/permalink.php?story_fbid=pfbid025oXMQayTtJPxbFPE5WTLiHrJjsnKqsy7TksGRYrFqAWwsXjZkSmU9CNRM8geywZZl&id=100085858021955

Edited November 19, 2023 by JumpingFrog

[Colin Lindsay]

Various designs have appeared over the years, I have an uncut manifold for the Weber, it's a blank so never fitted in anger but can be drilled and tapped to take studs for the Solex manifold and any Weber carb you have or want. Never saw another so no idea of where it was made.

 

[rlubikey]

Eric, as JumpingFrog says, there's loads of info over on the Standard forum. However, I'm pretty sure the rear carb of a twin carb setup will clash with your clutch m/c. DanMi's manifold may work. I've just put my old TriumphTune catalogues back in the loft, but I'm pretty sure they did a 6-port Weber manifold like that. Alternatively, moving the clutch m/c over to the right and putting a jog in the pedal to keep it in the same place may give you enough space, I don't know. This is what I had to do for my engine-back Spitfire, but the fuel injection takes less space that carburettors.

However, to get a significant number of extra horses, I think an 8-port engine with the consequent in crease in capacity is required. 1300cc if you like revving and working the gearbox. Or 1500cc if you like torque and a more laid-back driving style - like me in fact! In either case, the twin carb setup will give you the same problem. However, a single carb so-called "log manifold" I believe will fit. John Thomason tested this manifold back in the 90's and found a small loss in peak horse power (2~3hp was it???) but more torque and better fuel economy.

Cheers, Richard

[Eric Smith]

Hi guys

Thanks for all of your thoughts and ideas.

Joining this forum has so far been a goldmine of information and the advice is brilliant - trying to get information these days has to be done this way and I appreciate how you all give up your time to one off restorers like me!

Many many thanks 

Eric