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Hesitation re-visited

600 Views 5 Replies 5 Participants Last post by  white66coupe1
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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· Gone but never forgotten
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Thanks for the update on the Edlebrock. I have the 1406 on my '66 and the 1405 on my '69. I had switched the carbs, and the '69 also had a bad hesitation using the 1406, so I swapped back ... I think mine was the same problem ... running lean (1405 is jetted a litte bigger out of the box).

I'm curious to hear other responses about your "2 track" mark with an open rear. I, too, have an open rear in my '66 and can also lay down two marks. Also, like you, I didn't think this was possible with an open rear, so I'm as confused as you *LOL*.

Fatter tires will help your traction problem, but won't make it go away /forums/images/icons/smile.gif. I have a serious traction problem as well with my 3.00 open rear running 225/60x15's in back.

If you always do what you've always done,
You'll always get what you've always got
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