stunned_monkey Wrote:Changing over to the larger intake venturi (which I could have sworn I did retrospectively the last time I worked on Flopsy, fixing all the vacuum leaks etc)
Not when I measured it at EuroTech.
stunned_monkey Wrote:................ will lean off at idle and INCREASE fuelling at higher RPM. The flap's got a larger surface area, hasn't it?
Reverse of what you said. Fix engine speed. Air consumption of engine constant. Smaller diameter venturi/ metering flap displaces down more for given air flow through compared to larger diameter venturi. Lowering the flap increases fuelling.
stunned_monkey Wrote:the 066 (F series) CPR and 038 (E series) CPR have an identical warmup curve, but vastly different throttle deflection enrichment functions. This can be exploited, but will skew a fuelling test conducted at a standstill by revving the engine...
Test was done with this vac line disconnected and plugged negating engine vacuum on CPR.
stunned_monkey Wrote:The only true way to investigate fuelling away from a rolling road is to data log from a wideband lambda probe plugged into a computer.... a service I now offer.
Should have been done as part of development.
Cheapest mod that can be done with the car is fit a (nice-fitting) de-cat pipe, and fit the MATCHING venturi, fuel distributor, spark distributor, CPR from the Volvo B28E. Also not fit fuel lines that pulse the fuelling, balloon and fall off.
Claire could increase fuel economy now by hanging a couple of buckets underneath the exhaust pipes to catch the fuel dumped out of the back then pour it back into the tank after filtering the carbon out.
I will personally check Claires engine over and perform qualitative fuel pressure tests, CPR tests, fuel injector spray pattern tests, ignition curve tests etc to get it running right.
NickT
ps EVERY car is more economical on a long run.