by FredTransit » Fri Mar 06, 2015 10:54 am
At least with a pickup you have very little wind resistance. My first van was a Mk1 V4 LWB. It wasn't landspeed record quality, but was OK, I never took her over 55 on motorways. Can I ask why you need more power? Do you work the truck? If not, and there's no mechanical problems, maybe you need to get used to driving a classic transit? Give the old girl some time.
If you really can't accept life in the slow lane, your only option is an engine change. Quick addition of a bullnose gives you the choice of pinto, V6 and V8 from classic petrol engines, DI and TDI from slightly later diesel. You can go for later engines too, but they take more work, it just depends on your skill level or how deep your pockets are