I’ve bought a 1975 1.8l that the previous owner rebuilt the engine to 1.9l but it hasn’t run yet.

New NPR 96mm pistons and cylinders
Web cam and lifters from Pelican. (Carb engine cam)
009 distributor ( advance curves to go with cam and carbs)
Twin Weber 40 IDF carbs

Getting ready to reinstall the engine after doing hell hole surgery and repair. The main jets are labeled 115.
Questions :
1)Is that a good jet starting point for tuning this engine configuration?
2) Should I weld in bungs for O2 sensors in the exhaust for tuning?
3). Recommendations on what break-in oil to use?

Thanks
Tim

you will need 28mm main venturis.

I'd start with 130 mains, 200 air correction, stock F11 emulsion tubes and 50 idles.

Pierce manifolds is the best source for stuff IMO.

Yes to WB02!

Agree with techninja except the main. I'd start with 115 and work up from there.

@technicalninja and @nditiz1

Thanks
I’ll do some more digging and figure out what’s in these carbs for the other components.

Tim

The PO seems to have the right setup for starters
115 main
28 mm venturis
50 idle
F11 emulsion tubes
200 air correction

Will add the WB02 and figure out if I need to change something.

Thanks
Tim

You got LUCKY!

I still think the mains need to be fatter, but the WB readings will show which way to go for sure.

One problem I've seen a bunch recently is shaft bearings getting rough.
They didn't have enough lubricant when they were new, and most are old now.

Turn throttle shafts by hand. Should be perfectly smooth/no sticky spots!

Almost all of the 4 sets I have now need new bearings and throttle shafts.
Out of 8 Carbs only 3 are OK...

Thanks, the shafts turn smoothly, not sure how much use these carbs have gotten. I lubed them with light oil.