[VWNate1]

These are dead simple to tune, I hope you have a dynamic timing light and a tach/dwell meter ? .

the carby has _two_ idle stop adjustments, one is electric and t'other is a stop screw .

First things first, open the spark plug gaps to .035" .

The initial timing is about 7 degrees with NO VACUUM SIGNAL, once it's running you can and should use the advance dial on the back of the timing light to set the full advance to 32 degrees, vacuum connected at 3,000 RPM .

Remember : it's critical to use the proper vacuum advance port on the carby so there's NO VACUUM SIGNAL at idle, and the vacuum comes in as soon as the throttle is opened .

If there are bolts/nuts at the very ends of the manifold, it's wrong and probably has an intake leak .

Easy enough to check, use starting fluid or other flammable aerosol when the engine is idling, don't forget to spray up from underneath as that's often where the minor leak is that causes poor idle .

If you're still running points, use the dwell meter to set the dwell to 33 degrees when cranking the engine with the plugs out and cap off, adjust the points as the engine is cranking, it'll be much more accurate .

Often a stock 1975 > HEI dist, from any junked i6 Chevy/GMC/Buick/etc. is under $50 and bolts right up ('75 ~ '77 uses a separate coil) and will *instantly* give you more power, better idle, faster starting cold or hot and increased fuel economy ~ no downside possible .

I used one on a worn out 250 that fouled the plugs every 250 miles, after adding the HEI it ran good as new again in spite of the oil use .

Tuning i6 engines isn't difficult but seems to be a lost art these days .