| mgarblik |
10-21-2022 07:29 PM |
Little update on new bathtub intake for street use. I now have the engine in the car and have driven it about 100 miles. The little issue between 35-50 MPH, light throttle was an eye opening experience. After 5-6 hours of tuning and tweaking the carbs, I could get it better but still didn't run and feel just right. What could be wrong with the carburetors and intake? NOTHING AT ALL as it turns out. In desperation I started thinking, "what was different in the car than on the dyno" Pulled out the timing light and started tracking the timing. At light throttle, high vacuum where the problem was happening, the timing was almost 50 degrees BTDC! I unhooked the vacuum hose, plugged it and went for a drive. Ran much better, but rich from all my carb changes. Took off the dist cap which was plenty difficult and found my vacuum limit tab I put on had come off and was laying in the dist body allowing a full 20 degrees of vac advance. I had it limited to 10. I brazed the tab back on and now total timing is right at 40 degrees BTDC with vacuum, mechanical and initial at 2000-2600 RPM light throttle. Now engine runs great after returning the jetting to the dyno best tune. This manifold runs great on the street, idles really smooth and has excellent throttle response. Now I just need some room under the hood to get some air into them! Hood scoop coming soon. BTW, this set-up won't win an economy run. I used 20 gallons of gas on the dyno and I doubt it's getting 10 MPG in the car. It is getting way more than 10 SMILES per gallon though.
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