Your van should have an svda dissy anyway - it's what VW fitted. The vac advance helps on part-load throttle. It's unlikely to have any effect on mpg. The vacuum signal for the dissy comes from a different place (above the throttle plate). It's not straight manifold vacuum. Little point in doing anything with the air filter, as airflow isn't limited by the stock air filter. You'll struggle to improve things in a van weighing a ton and a half, powered by a 1600 engine. Best remedy is to fit a bigger engine or, def, nicely set up twin carbs.
Twin carbs is on the list. I'll have to save some pennies first I think it would make sense to fit a new exhaust and higher lift rockers at the same time. I had a fire in my air box when I first bought the van, so I needed to buy a new element anyway. Cotton is way better than a paper element plus you can clean and reuse cotton filters, better for the environment.
I'm not a fan of the K&N air filter. Fitted one years ago to one of my cars because that is what we did as kids and it resulted in flat spots and lack of power. It's brilliant for air flow but what it does is weaken the mixture because it allows more air in. You may want to experiment with the carb set up. It's just a thought.
Once the new dizzy and k&n filter arrives I'll adjust the carb at the same time. I'm sure it's running a little rich at the moment anyway judging by the state of my spark plugs. Sounds like the vw air cooled engine is a very sensitive beast!
All engines are sensitive, just modern ones have electronics and feedback from sensors to correct things when you make a change or when stuff wears a bit.
It's all good but you're screwed - you bought a van with a motorbike engine. lol 25 mpg - 28 - 30??? what's the difference?
I don't expect to 'tune' anything just to make sure the carb is setup right for the dissy and air filter I'm running. Whats wrong in that?
Nothing Cat - just mention any hocus pocus device on a car forum, then defend it and you're going to get flack. That just how it is. Maybe we're cynical, but I prefer to think realistic. Don't take it to heart, nothing personal. As you say there are things you can do to ensure you engine is running as efficiently as possible, but I'd say luck (live somewhere flat), having the wind behind you, followed by driving style top of the list.
Indeed. Pump your tyres up, empty all the cr*p out of your van and have a light right foot...that's the best approach.
