Drove her down the road a couple of miles and back and zero stumble or hesitation. I'm callin it fixed.
Manifold Vacuum Experiment
- Thread starter RustyRatRod
- Start date
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Even at a slow roll in third, I back out and then stabbed it and she started rippin up the right rear. It's never done that before because it never had a proper pump shot on the primary side. Not bad from a truck with an 8800 pound GVWR.
We took her into town, a little over 25 miles round trip. She runs fantastic. Stumble completely gone. Now with the vacuum advance on manifold vacuum and tuned for it, it runs cooler and better. Kitty's kinda mad though. I shifted into 2nd in downtown Gray and stabbed the gas and she smacked the back of her head into the back window. Whoops. lol
I want to come back to this and report on Vixen. We drove her to Milledgeville today to a small cruise in and to grab breakfast biscuits. Then, went to Harbor Freight to get a hand siphon and finally WalMart for cat food. All in all about 60-65 mile round trip. I can tell a bigger difference than I first thought. Much like Gladys, Vixen feels stronger with just the throttle "cracked" going down the road. It just took a little more distance for me to recognize it. She didn't miss a beat. Also, without a doubt, she's using less fuel and running cooler as well. I'd say this experiment was a double success.
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Another update. I haven't calculated mileage, mainly because I never have and there's really no point, because I wouldn't have a concrete base line to compare to. That said, I can tell there's been a big improvement in fuel mileage doing this mod. I did this back in February. Now, understand, we don't drive Vixen everyday. But, sometimes when there's a long stretch of good weather, we do. I have not filled up since February. She had a full tank when I did this mod. We've actually driven her a pretty good little bit between then and now. Sometimes daily. As before, the gas gauge would move "about" 1/4 tank from our house to Gray, drive around a little in Gray and back home. All that is probably about a 30-35 mile round trip. Now, the gas gauge moves "about" 1/16 of a tank, if that much. It's JUST enough to know it moved. I call that a good improvement. So if this is something you've thought about doing, give it a try. Record your settings before hand though, so you can return to them if you don't have the same results. What can it hurt, right?
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