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Discussion Starter #1
Ok, today was a pretty good day of working on the stang. Here is all that we did.
I have 2 intakes and 2 carbs for the cleveland...Today we tried every combo of the 4 to get the best street power (mostly idle to around 3000 RPM). The manifolds are a street dominator single plane and a preformer 2 plane. The carbs are a street avenger 670 by holley and a 600 CFM by edelbrock. After trying all of the combos, the best is the performer intake with the edelbrock carb! The holley has no low end power...It only has the power when the secondaries open. I have had it re-jetted and run on a flow bench and a dyno motor, and it should have killer power over the edelbrock. But when I put it on my car, it just plain sucks. I have had it with that thing. Maybe I just got a bad carb. I dunno. I am thinking about getting a 800 CFM edelbrock, maybe then I will be set. I think the 600 is a bit too small for the 351. Anyway, after we got done with that we went to check what my rear-end rato is. There is no tag left and I cannot see the # stamped on the top of the case. So we jacked up the rear, wedged the toolbox under one of the wheels so when one tire spun the drive shaft would spin also. I marked the DS, and counted how many times it spun with 10 rotations of the rear tire. The ratio I got is 15 revolutions of the DS to 10 roations of the tire, or a 1.5:1 ratio. We tried different spins and came up with 1.50:1 every time. I knew my ratio was bad, but not that bad!! I didn't even think they went that high!! I thought that We did not do it right, but we did! This is probable the answer to the poor low end/take off's!! Has anyone heard of a 1.5:1 9 inch? Well now I know my next project! 3:5:1 Posi, if I can find one!

Well, I am rambling...Please post if you have any info on the topics above.
Thanks!!
Matt
Oh, one more thing....Why did I get shocked when I touched the insolated spark plug wire when it was ideling? If it zapped me because i am a ground, wouldn't sparks ark from the wires to all of the metal gound on the motor? I don't get it. For thoes of you who have never been shocked with a spark plug, it is not a plesent experience!
 

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You need to re-do your axle ratio test.
Try turning the tire only one revolution, not 10 or 15. Then note how many times the DS spun during the one tire revolution.

There are no 1.5:1 ratio's available for a 9inch rear (that I know of anyway)...the highest ratio is 2.75:1.

The easiest way to tell what the car came equipped with is using the code off the VIN tag on the door (if its still there).
 

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Discussion Starter #3
yes, I would have done that, but the door tag is gone. Also it had a cleveland 4V that someone took and probably took the rear-end too. I will go out and turn the tire once and see how many times the DS turns. BRB...
 

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Turned the passengers side tire one complete turn, while holding the divers side locked in place, and the DS turned exactly 1 and one half times, which equals 1:5:1 ratio. I don't get it!!!
 

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I wouldn't use the tire to turn the driveshaft, use the driveshaft to turn the tires. Make sure your drums aren't dragging, which would cause one tire to lag behind the other, and throw off your count. You can do it by yourself if you mark the inside of both tires with a piece of tape. Spin the driveshaft with your hands and count the revolutions. If the tires go out of sync, you can stop one with your foot and continue turning the d/s until they sync up again. Pretty easy to do this way. BTW, by stopping one tire, you were factoring in the gear ratio of the differential gears as well. I believe you have a 3.00: 1 gear, considering the even numbers you were coming up with.
 

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Your spider gears are fouling you up. When checking your rear gear ratio that way the spider gears will knock the revolutions of the driveshaft in half. To put it another way. To properly count your driveshaft revolutions to establish gear ratio, you can turn both tires one full turn, or turn one tire two full turns. That equals one tire revolution. You have a 3.00 gear ratio in your car.
 

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Yes this is true if you hold one wheel you get half of the ratio so you have 3.00 to 1 gears.This isn't a bad way to do it because its hard to get both wheels to turn equally sometimes.

<font size=-1>[ This Message was edited by: frdnut on 3/18/02 12:24pm ]</font>
 
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