Spitfire carb mods!!!

[Cunno]

Hi my 71 spit is currently running on twin SU's that are long overdue a full overhaul but before I decide does anyone have any alternative fuel / carb ideas I could consider I have heard of spits running on 4 single bike carbs..... What ideas are out there.

Gaz

[Nick Moore]

Bike carbs are said by some to be very good, but mostly by the people selling them. You'd need four, and then a custom manifold, linkages, you'd then have to set them up, and for probably very little gain on a standard-tune engine.

Webers / Dellortos are easier upgrades, either one or two. Of the two brands, Dellortos are said to be better designed and easier to set up. However, you'd again need different inlet manifold(s), someone who knows what they're doing to jet them, and any power gain for a road engine would be minimal. Fuel economy would suffer if they weren't jetted optimally.

Reconditioning the twin SUs is your best bet, they can be jetted to suit even seriously fast road engines if necessary, and will give good fuel economy. An alternative often overlooked is fitting a single 1.75" SU, which is supposed to provide as much power as the twin 1.5s, and better low end torque. It just doesn't look as impressive!