Modifying SU carbs to create clearnce under a stag bonnet

[russ spake]

Hi, I've heard that the tops of my SUs can be modified to make room for a standard bonnet on my stag, without a bulge. Is that right and anyone know where I can get it done? Russ

[jrv8]

Hi Russ,
From memory , you need to fit the early SD1 dashpots as they're lower than the later ones, and the linkages need to be modified.
I saw this mod done to a Stag a few years ago and it worked well.
I should be able to look back on our records and tell you what needles were fitted .
Jim

[ChrisJC]

Are Strombergs any lower?

Chris.

[badger]

My stag (3.0V8) runs BDL needles in SU HIF44's. No mods needed, other than the removal of the paxolin spacer between carb and manifold (no adverse effects as yet....), a slight bit (minor) of relieving to the edge of the rocker cover and a bit of modding of linkages to utilise the original stag linkage and manifold adaptor.
I made 2 adaptor plates from 10mm thick aluminium to allow me to use the original stag elbows and air filter setup - the adaptors fit between the carbs and elbows as the bolt spacing is slightly different. Top bolt lines up ok but the 2 side ones are exactly half a bolt's-width off. I got around this by making the bolt holes in the adaptor plate a larger diameter than the std 8mm, screwing in 2 home-made stepped (offset) studs then sliding the adaptor plate over them before fitting the elbows and top bolt, using nuts on the ends of the 2 outer studs. Quite a few people have looked at it and not instantly put their finger on what it is that "seems different" from normal, that's good enough for me! No more dodgy fuelling, slightly better pick-up and better cruise economy as well.
Dodgy drawing of offset stud below:-

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[badger]

Nuts! It didn't show the offset stud as I'd intended, but no doubt you get the idea......

[camprofile]

For machine SU's call the Brighton Stag Specialist on 01273 700861




Nige