New World Datsuns...

How much closer is said house to Pasco?

Lol, yes, a garage with horse area too. And unfortunately, further from Pasco buddy.

Dick.

The best kind of garage comes with a house attached

Im kinda a fan of detached garages. Quieter for the people in the house.

you get left alone alot more also...less wife/kid distractions

All good points.

Here you guys go!

https://youtu.be/abojtKyiW2Q

Alright, finally got the AFR gauge re-installed with a new sensor. It's working great. Have to do some top speed loading for fuel mixture, then I can set the needle height accordingly. Still having idle issues, but ordered some Grose jets today from Moss Motors. That should solve that I think, I'll re-check the floats. But I'll start on the top end, then work towards good idle. Either way the car runs, so a little more fiddling and I should have it.

Getting really close. I love the concept you captured with this car.

Still waiting for you to drive that thing here.

Getting close. Only 6 weeks or so until Jethro Tull and Canby!

I'll be here when you come back.

Alright ladies and gents, for those who don't know, gross jets ordered from Moss Motors are NOT the same thread pitch as the needle and seats found in the SU carbs, or at least the Datsun version. All my lids are 6x1 mm. The gross jets appear to be 1/4"x28 or something. Either way, it explains why I snapped off the one trying to install. They're really really close, but just not close enough. The new gross jet is .010" larger and the thread pitch appears to both fit 1.0 pitch, but trust me it doesn't work. Off to go get a 6x1 die and I'm going to try to fix up the gross jets so they'll work. We shall see.

Failure of test drive two weeks ago has come down to a needle and seat not tightened in the forward carb. For Pete's sake. That really got me down. At least it was something simple. Off to fix and re-test.

I changed my mind. Carbs were a bad idea. Put the EFI back on.

HOLY MOTHER FUCKER!!! I figured it out. Fucking balls! So on a Weber 32/36 which we all know and love, the needle and seat is a brass piece with a viton-tipped needle in the middle that hangs down to be actuated by the float. In the SU which I currently have, that needle and seat style is instead two pieces for the needle. It's a viton-tippod piece of brass, and a spring, and another piece of brass, and the float actuates against that.

I had correctly set the float level 1/8" from the top lid, as indicated. What I didn't realize is unlike the weber, because that spring is in there, there's about 1/4" of travel in the spring where as soon as the float even BREATHES on that needle, it's shut off, and the float can still travel upwards another 1/4" before reaching dead stop.

So what's been happening is at idle it has enough to run barely, and when WOT, it has enough because the float is sunk. But because I adjusted the tab for the top of that swing, the float sits way the fuck too low and consequently shorts the bowl for fuel!

Fuck fuck fuck fuck FUCK!! Now that I've figured that out, I'm going to go get the proper tap and try to re-tap two of the bowl lids for the SAE thread pitch of the gross valves and use them instead. That should sort things out. If not, I'll have the other two and I'll get new needles and seats and adjust accordingly. Just when you think carburetor bits are similar enough, right?

Alright, re-cut the Grose jets to 6mm x 1.00 thread pitch. The stock Grose jets are 1/4 - 24, yes, not 20, not 28, but 24. A goofy fuck size if there ever was one. Good luck finding a tap for that on a Saturday! Bought a fresh die, just enough material to re-thread perfectly. So Grose jets are in. Similar issues to original. Idles, but at 1100 rpm, if you go WOT, then let it drop, it dips down to 7-800 and then back up to 1400 before settling at 1100 again. If you have the idle set at 900 rpm, it will die as it comes down.

Re-adjusted the float bowls quite a bit farther down after a run high and shutoff indicated the fuel level was too high in the needles. Basically, they are "incorrectly" adjusted so the floats are level with the top plate (like a Weber) when turned upside down. Previously they were canted so the front edge was 1/8" from the lid, which is technically the spec from what I've read.

Re-checked timing. 13 degrees. Vacuum advance works, and it's connected to the little port behind the bell which has no vacuum at idle. Once you open it up, it advances.

To make matters more annoying, I have a chee chee chee bird in the rear carb. A squeak whistle something that sounds like an intermittent chickadee. I've sprayed brake cleaner all over, no luck. Vacuum gauge holds steady. I can't find leak one, yet it's there.

Fuel pump is back where the original EFI pump was, it's a 9 psi unit, regulated down to 3.5 psi roughly with that cheesy dial Mr. Gasket fuel pressure regulator. It's not great, but the pressure gauge does indicate it works.

Still have decent performance, but the car should idle a lot better. Tempted to put the more worn out 4 screw SUs on to see if the noise goes away. I've eliminated all the vacuum sources besides vacuum advance for testing. Maybe I should make an adapter to the SU manifold for dual Weber 32/36s? Help me out here guys, I'm losing the battle. What am I not thinking of?

Does manifold vacuum hold steady on a gauge? If there's (gauge) needle flutter you might have a valvetrain issue causing audible backflow. Just spitballin'.