Forum back online. Please post!
0 Members and 2 Guests are viewing this topic.
What carbs have you got? because the Strombergs aren't famous for anything but becoming trouble whilst the SUs are very nice carbs and worth a few bob because of it.If you are getting lousy economy on carbs, try a new jet kit first (needle and jet etc). The biggest thing abvout V8s is that they cams can wear and this causes high fuel consumption because it screws up the valve timing and lift, even before it becomes obvious with a knicking at the tappets.With a worn cam or even just cam chain you won't improve your economy that much, if at all.ALSO, start by fitting the exhaust system from an EFI, not the fuel system, the biggest gain in power on the 3.5 EFi was the exhaust, the biggest gain on the 3.9 was the camshaft. If you want to fit the 3.9 system which is bigger bore you need the later gearbox crossmember which doesn't protect the exhaust as much.Don't bother retro fitting the 3.5 system either, they can be a lot of trouble.That said the 3.9 will be running in non-diagnostic mode unless you retor fit a bunch of sensors, it doesn't need them to run but to run at it's best it does.
Then that's what I'd do, fit the Sus and get them tuned up properly, spend any time and money you had to hand on fitting a decent exhaust and plugs/ignition service etc. A V8 in good tune running SUs will pretty much be the benchmark for V8 economy anyway.