Question regarding electric fuel pumps

[bikewiz]

So I installed a Facet 40105 pump from MS which is rated at 3-4.5 psi with 30g/hr I think it may be too little flow for my 1293 w/HIF44. It runs fine at idle and with no load but leans out with any load. The AFR is 14 or so at idle and 16+ when any load is applied. I'm running a modified needle, which with Dan's guidance last year, I got to run really well across the revs based on the AFR and "drivability". The changes I've made besides the pump is a refresh on the motor but no changes to the cam or C/R (other than a new set of rings) All of the hoses and hard lines are of the same diameter as they were with the mechanical pump, it has different routing but similar length.
Before I started the car I ran the pump into a container and it flowed well but I have nothing to compare it to in regards to the mechanical pump.
I've read that it's more of a flow consideration than pressure as you need to keep the float bowl full? But you need pressure to increase flow?
So I'm wondering now if I need to try a Facet 40106 which is rated at 4-7psi-32g/hr. I believe MS says this is for "fast road"

[MiniDave]

I'm surprised that 30 gal/hr isn't enough - can you use 30 gal of fuel in one hour of driving? Even flat out?

Maybe you need a better needle due to the improved compression/vacuum draw??

[94touring]

3psi is all you need. I wouldn't go over 5psi on a carb. I run a 3 psi on a 1430cc with twin hs4s without issues.  Probably your engine refresh got you a better ring seal.

I ran the same electric pump on my bus that's a 2180cc with twin dual idf 40 webbers too.

[mascher]

30 gallons per hour would empty a 7 gallon fuel tank in less than 15 minutes. It's unlikely you need more fuel but you may need less air. I would look for a vacuum leak.

[bikewiz]

So I checked for leaks. None that I can find with spraying carb cleaner at all of the mating surfaces and pivots. I do have a slight amount of gas weeping somewhere around the fuel inlet which I'll try and find and fix. I rechecked the timing right now it's 8° at 1050rpm idle 30-32° at 5000 it was hard to get an accurate reading by myself at 5000. I lowered the jet a little, maybe 1/4 turn. I polished the modified BDL needle a bit more.
Numbers now with it fully warm are 13-14.2 at idle and 16+ at WOT still lean on acceleration. Steady state at 3k it's around 15ish. Plugs look pretty good, maybe a bit lean.
So I think I may be going in the right direction.
So a couple more goes at the needle and figure out the weeping gas.
And try and fix the oil leak from the front of the motor 

[MPlayle]

Sounds to me like the dashpot spring may be the stiffer one and you may need the softer one to let the piston rise more during WOT?

[94touring]

Sounds to me like the dashpot spring may be the stiffer one and you may need the softer one to let the piston rise more during WOT?

Softer spring = leaner cruise
Stiffer spring = richer cruise

Thicker dashpot oil = richer tip in on throttle
Thinner dashpot oil = leaner tip in on throttle

Think of it like this, when the piston is lower, less air flows into the engine, but at an accelerated speed ( bernouli principle).  The pressure difference from the faster moving air pulls in more fuel than it would otherwise, even though it's at a leaner needle station.  Now raise the piston all the way and it goes very lean because of all the airflow, and with less pressure difference. 

[MPlayle]

That is one piece I always seem to get backwards.

[bikewiz]

I'm definitely getting closer with the needle and the general driveability. Idle at 13.2-14.5 cruise at 3k 14.9-15.3 still a little lean stomping on the throttle.
A question I have is, beyond the obvious, that the jet height affects the fueling, is it better to keep the jet at a certain height range (ie: no more than x below the carb floor) and adjust the needle or does it even matter? I would think the lower you adjust the height to richen it up the less efficient the fueling as the jet gets "deeper in the hole" so to speak. Or am I over thinking this....

[94touring]

You're probably over thinking that part.  What's wide open throttle giving you right now?

[bikewiz]

You're probably over thinking that part.  What's wide open throttle giving you right now?

I see 17+ it's hard to view when I should be paying attention to the road. The mistake I made installing the AFR gauge is putting it too low on the dash instead of closer to line of sight.

[94touring]

17+ the whole time or just for a second?

[bikewiz]

At around 3-3500 with my foot in it it spikes to 17+ then slowly goes down but it could be from me not keeping in it and pedaling the throttle as it stumbles, then I see maybe high 15's to 16.

[94touring]

17 spike sounds normal, go with thicker dashpot oil and it will help that.  I'd adjust needle height to richer and then do another WOT run, but keeping a steady foot. If it stays above 14s for 500-1000 rpms, let off and keep modifying the needle.

[94touring]

Quick thought:  you have verified you are getting full open on your throttle with the pedal all the way to the floor?  This is more common than you'd think and will give you some lean readings when you think you're WOT but actually 75% open.

[bikewiz]

I'll check the throttle opening. I have the cable pretty tight but I have an adjusting barrel I can use to snug it up more. I'm using 20/50 VR1 oil in the dashpot, short of single weight V-twin 60 weight oil what would you suggest?

[94touring]

I'd just keep working on getting the mixture correct then.  It shouldn't hesitate on initial throttle spike once you get it sorted. 

[bikewiz]

So I'm getting closer. Its a little lean at 65 on the highway but decent for the most part around town and perfect at 45-50 with a steady throttle.
The throttle cable is a tight as it can be without affecting the idle.
Idle is steady at 1050 and 8 degrees.
Plugs look good.
I plan to check everything again and work on the needle a little more.
And I think I fixed the intermittent electrical problem by cleaning the connectors and lightly bending the sockets to make a tighter connection, this was of course after I wasted a bunch of time removing the dash to check every connector and ground.....