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Hesitation re-visited

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With regards to my post last week about hesitation with an Edelbrock 2121 and 1406 carb on my 289, I contacted Edelbrock and they recommended changing the step up springs and metering rods to a silver(8in Hg.) spring and a .073X.042(#1455) rod.

I did this today and re-adjusted the idle mixture and took it out for a spin. When cold, there is still some hesitation but is is virtually gone once warm. However I noticed a significant increase in response which means it was probably running lean to begin with.

Now, I have not had the car to a track yet but from the way it runs I would guess it would be around 14 sec. in the 1/4 if I could get traction. I have been considering changing the rear end from the non-posi 2.79 to a posi 3.25. I have a C4.

Well while out for my test drive I stopped on a lonely country road and without holding the brake I nailed the throttle. The tires are 195/75/14 and I immediately had rubber squeal. Then it stopped and I thought the trani was slipping but the tires had began to spin and smoke. I kept the power on and wound up leaving over 200 feet of rubber and smoking up the whole street. About 1/2 or so of the rubber was twin tracks. I was amazed that I could do this just by nailing the throttle with 2.79 gears. How did I get twin strips without having a posi?

Obviously this would limit my acceleration in a race. If I up the rear end ratio to 3.25 even with a posi this would make the tire spin problem worse. So now I am re-considering. What do you think I should do? Would fatter tires help?


Steve D
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I'm not a drag racer, so I can't help you with the mechanical stuff but I can tell you that the key to fast starts with a street car is to get the car in motion then build speed. Forget the smoke, just get the car rolling before you punch it and then shift as close to the peak of the power curve as possible.

As for tires, the bigger the contact patch the more traction you'll have. You can't do better than slicks, which are all contact patch. If you need tires that can do double duty, look for a tread pattern that optimizes the contact patch while retaining the ability to channel water.

Our Ponies
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