Originally Posted by Jerome
Mister Towed it isn,t my car, but I think it was a rather expensive rebuild(electronic)tacho from an Italian? car.
I have a question:i,am struggling with my Stromberg CD150 carbs,do the CD175 types just fit on the same manifold?
Hi Rob, the 175's won't fit on the standard manifold without adaptor plates as the studs are 1/4" (6.35mm) further apart to allow for the bigger throttle opening. You also need to use appropriate needles for your engine (I don't know anything about needle sizes on these carbs btw, so no point asking me for more details).
My 1.75's came via ebay with the adaptors included and the correct needles for my Vitesse motor already fitted as the seller had been running them on a Vitesse himself.
The adaptors are pretty basic (I suppose I should've taken some pictures before fitting them). They're about half an inch thick (12.7mm) with countersunk holes that take flush set-screws to attach them to the manifold using the threaded holes left by removing the original carb mounting studs. The wider spaced studs are pre-attached to the adaptor facing away from the manifold and you just bolt up the carbs with new gaskets at all the joins.
The only other mod necessary was an extension to place the throttle cable over the lever that operates the linkage as that lever faces inboard on the 150's and outboard on the 175's, so there's a difference of about 4" (100mm) between their locations.
I've noticed a significant improvement in performance since fitting them, but I have to say I believe most of that is down to the old ones being worn out rather than any real gain from the bigger throttles. I had planned to eventually fit a Chris Witor flow balanced manifold, but I've just this second discovered that they no longer carry out that mod.
Anyway, good luck getting your carbs sorted.
I'm sure if you took your manifold and carbs to a machine shop they could knock you up something suitable easily enough (assuming you can't do it yourself).