Today has been a good day, I've re plumbed the PI so that the low pressure spill from the metering unit returns to the low pressure fuel filter union and the higher pressure spill from the PRV is totally isolated from that circuit and returns direct to the tank. I was concerned that having this high pressure spill joined to the low pressure in a "T" and then routed into the tank could allow the metering unit to become pressurised again. A pressurised metering unit will at best run rich and at worst, as we found out, run full rich and cause unnecessary but spectacular flame splitting form the exhaust!
Still looks like a rats nest in there! Once I'm happy with the thing I'll tidy it up!
Running the car with the various spills disconnected showed me that although the pressure is not great there is significant fuel coming from the PRV, indicating a healthy pump. There's very little coming form the metering unit indicating a healthy metering unit - it's new so it should be!I also replaced the passenger side weather strip on the door, what a shitty job! I may not do the drivers side one! I even have the right tool for the job but still it ain't easy!
I managed to trial fit my new K&Ns - hmmm, some fabricating needed here. They fit BUT the middle one is tight (acceptable) and the forward one fouls the throttle linkages (unacceptable!). There's shed loads of room there so I think I am going to see if I can find some thin wall Ali tubing with a 48mm outside diameter and fabricate some ram pipes to connect the filters to the throttle bodies but in a stand off way so they don't foul.
If I can get the right tubing it'll work and may well help - I won't be able to get bell mouths in there but the filters housings are rubber so maybe I could squeeze some in?
Tomorrow I'm going to see if I can fit up the new headlights with their fancy blue bulbs :-) I also need to go for a long test drive and see whether my plumbing has improved things! There's also the small matter of renewing the front wheel bearings and the steering coupling and and and....