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Discussion Starter #1
We are running a 545, with a c-4, the car is 3200lbs on a real 28x10.5. The best we have run is a [email protected] Would a powerglide be faster than our current setup. I would like to know if you have made this swap and what the result was.
 

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Way out of my league.....

Y'all are way over my head here, and I hate to hijack.

But if you have a 2.45 1st gear ratio in the C4, and the glide has 1.76, would it be easier to adjust your rear gear ratio to make up the difference??


ie: 1.76 X 4.10 (rear gear ratio, I pulled it out of thin air) = 7.216 overall first gear ratio.

Divide 7.216 by 2.45 = 2.94:1 for a rear end ratio. If you wanted to round up to 3.00:1 or add roughly 10% for 3.30 or 3.25:1 to make up for any inherent parasitic losses from using the C4, would it all come out the same??

I constantly hear about a 'glide's ability to calm down a launch, but is it just a ratio thing or is there more involved?? I know a drag car with a 3 or 3.25:1 ratio sounds strange,(edit::: I forgot about those top fuelers) but the math is bugging me.

Sorry if I went off the deep end here, and I don't have any advice. Just brainstorming and looking at all options. Everyone feel free to tell me why the math is wrong or I'm just confused.

I can't even imagine the can of worms involved if we include the converter in the equation.

If nothing else, here's a bump to the top.
 

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Cletus66: I will give this one a shot :).

I 'think' the reason so many people talk about the glide is when they have the power to 'pull' through the gears and don't weigh too much. The two speed Powerglide has dramatically less reciprocating mass. This helps the car run quicker down the entire strip.

Am I on track with this reasoning guys?

Have a good day!
Michael
 

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Hey Phillip, I've been thinking about a glide too...

I know I'm not anywhere near the 5.00 second ballpark but I need to change converters, and thought about going on and switching to a glide now. Soon I hope to put together a little more horsepower.
 

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A couple of reasons (my speculations) why glides work well behing a 385 series Ford.

1) There is so much torque there that it doesn't need the multiplication that a lower first gear offers to get rolling.

2) The reciprocating mass is so much that the engine does not accellerate as quickly and can't take advantage of the lower 1st gear as well as a smaller lighter (internally) motor.

3) What good is the low 1st gear if you have to de-tune your launch power to keep from blowing the tires off ?
 

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I've often heard that a glide is good for a tenth or two, provided your car is under 3000 lbs. or so. We've got a pump gas 514 in a steel Ranger that runs 5.80's. It's a J.W. Glide and it wouldn't do that with a 3-speed. Race weight is 2700 lbs.
 

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Oh, yeah.........That Ranger scales 58% on the front axle, and it carries the front wheels over the 60 ft. timers. So much for the tame launch. 4.86 gears, 32X16 Goodyears.
 

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I DUNNO. Not too many BBF's need lower gears in their Glide for a decent launch........unless maybe the car is really heavy. Does your car stay hooked up all the way down track? Any wheelspin at the gear change? 466fox? Are you still there?
 

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I picked up a little over a tenth when I did the swap. I had a 560" C headed motor in a stock suspension mustang with 28 X 10.5 tires and a C4 with no transbrake. I switched to a powerglide with a transbrake and picked up about a tenth. It choked the car off the line to help with traction. When it did spin though, the powerglide would instantly blow the tires off where the C4 would spin and still go.
 

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Sounds loke a fairly heavy car with smallish tires. Your take makes sense to me. I have less weight, 32 X 16 Goodyears.....It hooks like crazy on launch, then kicks 'em loose at the gear change.
 

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Discussion Starter #14
60fts

Our car seems to do what joe is talking about, it spins the tires but still moves, Our 60fts will vary alot, we have been 1.27 when the track is good, but it will fall to 1.35 or worse when the track is'nt hooking. I would like it to stay in the 1.20's.
 

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glide

I went from a C-4 with trans brake to a 1.76 glide with a brake in my 532 mustang @2800 lbs. C-4 60' was 1.54, glide with no other changes was 1.38. Rear gear is 4.30 but changing to 3.73 and expect to gain et and mph due to lots of torque. Don't be afraid to use a glide but be careful about switching the low gear, heard they cause the tranny to be less reliable. My motor was about 800 hp last season. Chris
 
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