Jaguar V12 - SU Carb Conversion

[mph]

Does anyone have any experience with replacing the original Stromberg carbs with SU's. ?

Kits are readily available and anecdotal evidence says that they give a decent increase in both performance and economy.

Reason I ask is that I'm considering an S1 XJ12.

I know fuel injection may be an option but I'm not interested in going in that direction.

[BDF!]

I tried that on my XJ12 S1, it was not as good an idea as it seemed on paper. SU carbs are bigger than Strombergs and they come so close from inner wing that you cannot fit any air filter and even the shortest trumpet doesn't fit which is not good for airflow.
You can fit a 6 pack Weber on the XJ12 S1 but only with very short trumpet because the bonnet is very close which again is not good for airflow. I tried it too...
ZS are not the best but you'll see they are not so bad when they are rebuilt and the engine is finely tuned.

SU on LHS are close from inner wing but you could fit some short trumpets


On RHS rear carb is very, very close to inner wing and master cylinder is also to close



My other XJ12 S1 with Webers. To use longer trumpets you'd need to modify the bonnet.

[mph]

Thanks that's very helpful.

I know they fit the V12 E Type without too much trouble but the under-bonnet layout must be more suited on those cars.

[BDF!]

SU and Weber conversions are for E Types, obviously not for XJ's