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So finally getting repeatable results! Got it running good in the fully warmed up mode and found that, for my engine, it needed way more fuel than I thought it would need. First though...
Ran it on the edelbrock for a week and a half- all was as near perfect as it could be. First full day of driving the engine would just shut off on moderate accel. Sometimes restart before the engine finished spinning down. Found my 3 month old MSD coil failing. That's 3 for 3 on msd coils for me (two pissed the oil out and this one failing under a load). So reinstalled my old bosch blue coil and it ran great. After a week of driving on the carb I decided to go back to the fitech in hopes my issue was the coil failing- and partly it was. First thing I found was timing was a bit low in my slow cruising/high vacuum so I added timing- it was a definite step in the right direction, but would still intermittently chug or stumble at these speeds. I began really paying attention to the afr readings and how quickly or far off the desired afr was going when it was chugging at a slow speed and found that when the afr would go richer than my desired afr it would run better- worse when afr went leaner. So I began adjusting my desired afr down until no more chugging. It has now been 3 days and it is staying consistently smooth now on my slow speed driving at fully warmed up. I am now able to cruise at 35-40mph in 4th (3.88 r&p with a 0.082 4th) and accelerate away smoothly. Next to the additional advance it is fueling almost exactly the same as what my edelbrock was. Saturday I'll be driving out to Orange to stop in and say hi to Aj so I'll see if the fuel economy will be the same as the carb (29.9mpg).
I'm still having issue when cold and without an inline thermostat for the oil cooler it does take a little long (especially on cold mornings) to get up to normal op temp. So, I will be installing one in the next few weeks.

Awesome great news!

Nice. Sounds like your getting it sorted out. Jealous you get to drive yours!

Good feeling aint it Damn u must be close to idle at 35 mph and that High of gearing sometimes I could use a .082 4th,I catch myself trying to shift to 5th ,, and I don't have one more so in my bus with that darn 4:86 R&P

Haha. Yeah, at 40mph it’s about 1800rpm. 45 is 2000.

Made it out to Low Bugget last weekend and got 28.8mpg on the drive down. Most of that was 65-70mph and about 2-3 miles of 80 to 90+ for some fun. A reoccurring proplem I was having was running like crap cold. I've narrowed the issue down to the same problem I had last winter- the center section is too cold going to cyl's 1&2. When I left my place Saturday it misfired bad and constantly until I pulled off a few miles up the freeway (had a friend following me out). My car hot soaked for 3 minutes or so. When we left there it ran great the rest of the way to Low Bugget (a little over an hours worth of driving). The drive back did not go so well- the misfire was present the whole way back. So it looks like fitech kind of freaks out with the misfire (unburned oxygen looks like a lean reading on the afr so the fitech reacts giving more fuel causing a rich condition on the good running cylinders). The good thing with the edelbrock is its a stupid carb and doesn't react to this. So, I'm switching back to my edelbrock and have ordered up a new 650cfm AVS2 edelbrock carb. I wanna see how the new annular discharge and adjustable secondary air flap work. Next summer I will be swapping engine cases so when its apart I will get back on trying to warm up the 1-2 side of the center section with electric heaters and an insulation wrap. But for now, I just wanna drive!!!

Haha we must be on the same page , I'm reading this and thinking "dumb old carb won't do this"
heated Snowmobile tape for under the grips works on the intake

Get me a link for that tape! I will definitely put it at the top of my list for heating cures. Thx!

wife sez I'm compter illiterat but any snowmobile supply should have em

The new AVS2 is on it and running great. Jetting very close to the older AFB design. Primary side is just about perfect so secondary side tuning will be starting. Still running the SafeGuard for boost timing retard and knock timing control. So far so good.
Fitech will be going into the race engine set up. Decided to go blow through with water cooled intercooler box and mounting all the injectors in the plenums. Header is getting started so hopefully wont be much longer now.

I take it AJ is building the header ? does/will he sell just the header?

Yea he is. I believe it will be something he will offer as a drag race header. No cooling system and can’t use a vw alternator.

I'm interested to see how the injector placement works out.
I was reading something the other day (maybe it was even on this thread, i don't remember?) that a guy was talking about how he picked up quite a bit of power by moving the injector further from the valves. He thought it was because it atomized better and he was able to lean out the fuel because of it. I thought it was interesting.

Hmm. That would be the complete opposite of even car manufactures- but our flat 4’s are definitely different. Manufactures go for as close to the valve and then direct injected directly in the cylinder. 15yrs ago the expected engine efficiency was around 78%. Now I’m seeing NA engines flowing 98%. It’s crazy what putting the injectors in the cylinders will do.

Beats me. I will have to see if i can find that again. I'm sure it was a N/A VW because he mounted the injectors above the dual TB's. Like up above the throats of them. Hanging in the air pretty much.