Gear ratios for drag cars

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64merc
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Joined: Sun Mar 31, 2013 12:27 pm

Re: Gear ratios for drag cars

Post by 64merc »

A lot of the small tire guys at our local track use a glide to help keep the launch less violent. With the old combination I would have trouble at the hit unless the track in good shape, that's why folks have told me to use a 'glide. I'm going to use my c4 and this is just an idea me and a bud was talking about.

64merc
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Joined: Sun Mar 31, 2013 12:27 pm

Re: Gear ratios for drag cars

Post by 64merc »

CALIFORNIA CALIENTE wrote:64merc;I would say stay with the C-4 you already have! A powerglide is OK if you build your engine combination,and set the car up to handle just two gears! Depending on what RPMs the new combo will make the best HP and Torque,you may need to change rear gears in order to keep the engine in its sweet spot! I would make some test hits just the way you have it setup now,see how it works!Pop can relax as I don't think there are any GM parts left in a race glide!!Of course I would go to a 5 speed Lenco or 5 speed Liberty stick,but that is just me!!! JMO , ROY.
Yep, I will have lots o testing when the new motor gets in. It would be sweet to have a Lenco or liberty, maybe some day!

b.guggenmos
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Location: Olympia, Washington

Re: Gear ratios for drag cars

Post by b.guggenmos »

Somehow I missed this thread. Like Roy I am a stick guy but since most of the people I know race auto's I have picked up a few things. The powerglide shines in a light weight high horsepower car. Typically a tube chassis car with alot of hp. The powerglide is pretty much bullet proof once you replace absolutely everything including the case and then spend a grand on a converter. Stick with your C4. They are good and a lot of fast Fords use them. They use much less HP than a C6 unless you get into the trick C6's that use Mopar internals but that is another story. Use a trans brake and a good converter and it will almost launch like a stick car.

Sometimes when I talk to guy's that race autos they talk about how expensive it would be to switch to a 4 speed. I don't think so. You can spend some serious coin on a auto trans and converter. Brian
1965 Comet Cyclone Drag Car Aquamarine, 351C, 4 speed, 5:14, ladder bars, 10.50@129mph
1965 Falcon Tube Chassis Drag Car, 347, Jerico, 4 Link 9.?
1970 Boss 302 Yellow, Deluxe Interior, Shaker, Slats, 4:30 Drag Pac
1932 Ford 5 Window Coupe

64merc
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Joined: Sun Mar 31, 2013 12:27 pm

Re: Gear ratios for drag cars

Post by 64merc »

Yep all the big hp cars at our local track use a two speed, and almost all the small tire guys too. I don't think I'll be one of the high hp cars but I am hoping for close to 800 and I only have a 275 tire. I just wonder what would it hurt to use a 3.00:1 rear gear and only first and second at the track.

pro64
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Joined: Fri Aug 05, 2011 12:29 pm

Re: Gear ratios for drag cars

Post by pro64 »

hey steve what r u planning for a rear setup. id say a set uv thirtyfive spline axles will be in order. would rather too much axle than not enough. 8)

64merc
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Re: Gear ratios for drag cars

Post by 64merc »

Harry I guess I'll just keep running the same setup I have now. I only have 31 spline moser axles in it now, so I'm gonna stress test them and maybe they'll hold up. After fixing the crash damage, new rear suspension, new brakes all the way around, new motor, and converter, I may not have enough in the budget for new third member and axles. I'm also getting away from the heavy steel wheels and getting some billet specialties street lights.

b.guggenmos
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Location: Olympia, Washington

Re: Gear ratios for drag cars

Post by b.guggenmos »

64merc wrote:Harry I guess I'll just keep running the same setup I have now. I only have 31 spline moser axles in it now, so I'm gonna stress test them and maybe they'll hold up. After fixing the crash damage, new rear suspension, new brakes all the way around, new motor, and converter, I may not have enough in the budget for new third member and axles. I'm also getting away from the heavy steel wheels and getting some billet specialties street lights.
Roy will chime in on this one about your axles. Get rid of them. I am surprised they made it this far. It can be really ugly when an axle breaks. I used to break 31 spline axles always in the spline area. Roy had one break out at the flange area. Not pretty at all. He can give you the details of why the axle failed. I understand budgets and all becuase there are many things I have and still do skimp on that I should not but one smart thing I did was invest in Mark Williams 35 spline axles and spool in the 80's. Brian
1965 Comet Cyclone Drag Car Aquamarine, 351C, 4 speed, 5:14, ladder bars, 10.50@129mph
1965 Falcon Tube Chassis Drag Car, 347, Jerico, 4 Link 9.?
1970 Boss 302 Yellow, Deluxe Interior, Shaker, Slats, 4:30 Drag Pac
1932 Ford 5 Window Coupe

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Boss/Cyclone
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Re: Gear ratios for drag cars

Post by Boss/Cyclone »

Yeah, you got to pay to play. I was at the track this summer when a guy in a 65 Mustang snapped and axle and then took a sharp left turn directly into the wall! The guy was taken to the hospital, but was fine. The Mustang did not fair as well.
1965 Mercury Cyclone former drag car, 1971 Boss 351 engine, 4 speed, ladder bars, etc. Now returned to a street car.
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Larry

CALIFORNIA CALIENTE
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Re: Gear ratios for drag cars

Post by CALIFORNIA CALIENTE »

Steve;I know your are tired of hearing this but get rid of those 31 spline axles!!! I broke a 31 spline Moser axle at the outside of the bearing running a mild 289,4-speed on a 10" M/T ET Street,flat tore up my Comet!!It sounds like you are planing some expensive up grades,I would suggest spending money on axles too!! JMO , ROY.
Real Racecars have 3 pedals
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vicegrip
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Re: Gear ratios for drag cars

Post by vicegrip »

The low gear and loose converter will put a lot more pressure on the tranny on the 1-2 deal you're thinking about.Even the best prepped C4 won't take that kind of power in that situation for very long or without a lot of maintenance.IMO

64merc
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Re: Gear ratios for drag cars

Post by 64merc »

Yea Roy your right, i need to price a new spool and axles and see what I can come up with or maybe find a used spool. Vicegrip I think you may be right about putting to much stress on the trans with what I was talking about. I do have a well built trans but it probably wouldn't hold up very long.

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