The Bugeye originally had 1 1/4″ twin SU carburetors. We upgraded to twin 1 1/2″ HS2 carbs shortly after purchasing the car. With the current restoration we are going to try a single 1 3/4″ HIF44 carb. We hope to attain equal performance without the need to balance twin carbs. The single HIF carb was routinely used on Minis with essentially the same engine. The HIF 44 is SU’s most modern carb of the period. The float bowl is integrated into the bottom of the carb body rather than a separate float bowl as with the HS2s.
Using the HIF carb requires the use of an appropriate heat shield with integrated securing points for the throttle and choke cables as well as a custom intake manifold sourced from Manifold in the UK. This manifold lowers the carb so that it will not foul against the bonnet.
After purchasing the HIF44 we sent it to A.C. Dodd in the UK to have him modify it slightly. The biggest change was converting the unit from manifold vacuum to ported vacuum. Bugeye Restoration Video Episode Fifty-nine reviews the features of the HIF 44 and explains the modifications made to it by A.C. Dodd to prepare it for use in the Bugeye.
https://vimeo.com/924772088/d53a91b278?share=copy
Episode Fifty-nine includes the following content:
0:05 – HIF 44 carb documentation
0:45 – Applications of the HIF 44 carb in other cars
1:37 – HIF 44 carb needle
2:20 – Manifold and Ported vacuum
2:26 – HIF 44 Carb heat shield
2:32 – Maniflow intake manifold
2:50 – Choke cable retaining clip
3:23 – A.C. Dodd HIF 44 modifications
5:33 – HIF 44 Hose fitting legend
5:39 – HIF 44 Throttle and choke cable connections
Setting up the HIF 44 for initial running is really quite simple. (more info to follow shortly!)
Setting the fuel mixture is the first step. This is accomplished by turning the fuel mixture screw shown in the image above. The image below shows the proper level of the jet:
The fast idle, or choke, is set by adjusting the fast idle screw against the cam. The images below show the proper setting. A feeler gauge with .018 blades is used to set the mechanism and then the screw is turned out until it just touches the cam at the arrow.
A small spring clip is used to secure the choke cable end fitting to the heat shield choke bracket. It is a friction fit and is just pressed down over the end of the cable ferrule.
A two piece cable stop is used to secure the choke cable to the choke lever:
Finally, we are using a K&N Cone-type air filter for the carburetor. We sourced this one from Moss Motors: