Tuning Dells

[Ron Roberts]

I switched my Kadrons for a pair of Dell 45s. The improvement has been fun. Much better trottle responce, and all around smoother operation. I also gained 2MPG (so far). My only concern is that I am running about 10* hotter on the oil temps and was getting some detonation around 1500 -2000 rpm if I load it. So, I retarded to timing a few which pretty well took care of it. BUT that caused it to cough on decelleration (only when moving not sitting and revving the engine) I am guessing this is beacause of unburned fuel igniting after the cumbustion. I am pretty sure the coughing is from the exhaust and not the carbs. Should I go up a notch on the idle jets and put the timing back where it was? Any recomendations?
2017
8.5 CR
009 now set to 25* full advance was at 29
34 vents
55 idles
150 mains
200 airs

Thanks
Ron

P.S. Next day now. I pulled all the idle jets and cleaned them. Each one seemed to have a slight resistance to passing a jet drill through it (drill had been through before) as if there was some gunk lining the jet. I put them back in and no more coughing. Next time I started up it backfired right at startup and now its coughing again on decelleration. I use the stock fuel filter, and it is new.