Fuel system An electric fuel pump can improve reliability and fuel delivery. Remove the mechanical pump and seal the mounting hole with a blanking plate and gasket. I found through trial and error that a 2-5 lb. pressure rotary fuel pump like the one from Carter has the best reputation for reliability (most solenoid actuated "thumper" models are to be avoided). Mount it near the gas tank with rubber insulating grommets to avoid excess noise and vibration. You should check to see that your pressure is within specifications, and you'll need a fuel pressure regulator valve. For solid reliability, there is nothing like a properly set up Weber carb. The most common model for 4 cyl. cars is the DGAV range down-draft 2 barrel progressive carb. Some have automatic chokes, and some are manual. Twin Mountain Induction and other carb shops sell kits. The Series III and IV GT model alpines had a 2 barrel Solex carb, and a Weber 2 barrel fits nicely on the intake manifold for this carb. Follow your mechanic's recommendations about air cleaners, linkage, and other modifications. Most gas tanks from these classic cars can use some refurbishing. I took mine out, removed the float and sender, and put a tow chain inside. After about 30 minutes of agitation to remove rust and scale, I blew it out, washed with solvent, and treated the inside of the tank with POR-15 gas tank coating. This resists MTBE and other nasty additives, converts rust, and binds any residual crud which could enter the fuel system. An inline fuel filter was also installed, and metal fuel lines were used where possible. Eliminate all leaks, and carry a haylon fire extinguisher in the car just in case. Haylon does not attack your wiring or create impossible cleanup problems. I run super unleaded with a lead substitute, but I'm considering converting my engine's valves, seats, and guides to more modern hardened units so I can burn unleaded gas straight. I've found quite a difference in various brands of gas, so find a couple that you like and stay with them.
brake system It has been said that British cars are hard to get running, but once you do, there's no stopping them. Actually, most Girling or Lockheed systems found on British cars are adequate to good. They do, however, require proper maintenance and occasional rebuilding. Girling recommends Girling or Castrol brake fluid only in its systems. Silicone brake fluid reportedly swells rubber pistons and seals, and conventional fluids
will attack them. The aluminum bores of a Sunbeam's brake cylinders are subject to pitting. While it is possible to polish the bores, new cylinders are recommended. An alternative is offered by White Post Restorations. For $30-50 per bore they will install a brass liner. Disc brake pistons are often hard chromed, and when pitted must be replaced (expensive). When replacement is required, you should opt for aftermarket stainless steel pistons supplied by Sunbeam Specialties and some others dealers. The new Teflon or semi metallic brake pads and shoes will give better service than the old asbestos numbers. Be extremely careful around brake dust, and wear a respirator. Later Sunbeams incorporated a Girling vacuum operated booster. This lowered pedal pressure and improved braking. These units are difficult and tricky to rebuild, and adapting a more modern unit might be the way to go. Periodic adjustment of the rear shoes and bleeding the system should be part of your maintenance schedule. New brake hoses and replacement of any damaged lines should also be mandatory.
Engine modifications My Alpine came stock with an early canister oil filter. I changed the mount to take a modern screw-on disposable filter. I also changed to an Allison/Crane electronic ignition system and Bosch Platinum WR9-DP spark plugs. Pay particular attention to gaskets, seals, and the sealing compound used for each. Use the best stuff you can buy, and always go through all gaskets when the engine is out of the car. It may not be possible to get at them easily once the engine is installed. It's also a good idea to replace the clutch disk whenever the engine is out, and a ball bearing throwout bearing (if you can find one) is a good way to avoid grief. Check the engine mounts, loose wires (particularly around exhaust system) loose bolts (these engines do shake) and keep all fluids topped up and changed on regular schedules. After experimenting with new synthetic oils, I settled on Castrol 20 wt. with an STP chaser. I experienced some blow-by with Mobil 1 synthetic oil. Remember to change oil and filter more frequently in dusty or hard service conditions. Also remember not to rev the engine before it gets full oil pressure. I use Slick 50 to reduce wear on startup.
Driveline After rebuilding several transmissions, I've learned a few lessons the hard way. British bearings have a bad reputation (indifferent metallurgy you know). Fortunately, most bearings can be cross matched to American, Japanese, Swedish or other good bearings. This goes for wheel bearings as well. When you're in the transmission, carefully inspect all parts, and consider replacing synchro rings, all bearings, shift forks, circlips, springs, and any other suspect parts. You won't be sorry, and will probably save in the long run. Gearboxes and rear ends are a good place to use the proper grade of synthetic oil with one exception. It is not recommended to use synthetic oil or additives with Laycock overdrive units, because the cone clutches could slip. By the way, once you've tried an overdrive on an Alpine you'll want to use your non-overdrive transmission as a boat anchor. I've also heard of some hearty souls adapting 5 speed Toyota transmissions to Alpines (good luck). British rubber seals also tend to be of lower quality than American counterparts, but are easily cross matched. Replace them when you can, using single lipped (not double lipped) seals.