manual vs automatic tranny

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Oct 24, 2007 | 05:15 PM

bigred66

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Tuned

Joined: Aug 2005

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manual vs automatic tranny

My friend has a 96 bronco, 5.0(140k miles), 5-speed manual, 3.55 gears, stock gears and 31in tires. I have a 95 5.0 bronco, e4od auto, 3.55 gears 31in tires and a newly rebuilt engine(2000 miles) with after market heads, intake manifold, roller rockers and E303 cam. He kicked my butt in a race. Is this because he has a manual tranny? I realize the E-cam isnt the best for a big vehicle but would it make that big of a difference. I'm going to look further into the matter because I feel something may not be right here. What do you think? By the way, we started from a stop light and did about three different trials and the speed didnt exceed the speed limit of 45mph. In some cases I even jumped the gun.

Oct 24, 2007 | 06:47 PM

Matt99362

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Your friend has 5 gears. His 1st gear (I believe) is lower than yours and he can shift more inside his "power band". Your auto is only a 4 speed, and will most likely get up to around 65 before it shifts into 3rd. This is not a transmission set up for quick races. However, in the long run, you'd most likely take him on the top end due to the modifications you made. Race him to 70 or 80 on the freeway and see who wins.

Oct 24, 2007 | 07:15 PM

ford_boy_1996

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Joined: Oct 2007

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From: Maine

I had a bronco and it had a GT 302 from jegs and a AOD with 3.55's and it was a slug untill I put a 4 speed std in it and then it had all kinds of power but no top end it would over rev at hight speeds. But like matt99362 said you would take you buddy in the long run with you E4OD

Oct 24, 2007 | 09:14 PM

blue beast

Posting Guru

Joined: Nov 2004

Posts: 2,155

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From: sunny fla sometimes windy

It takes horsepower to operate a torque convertor, So you automatically lose some
go go there. You could put a trans brake and then dump it and he wouldn't have a
chance off the line. The tires may both be 31 but all tires do not measure exactly
what they say kind of like a 2x4 actually measure them his may be smaller and give
him a bit of an edge too!! A bus motor has 100 more hp than the same motor in a
big rig with standard shift just to compensate for the power loss through the torque
convertor so if that figures to our trucks somebody good with math could figure out
the ratio of power lost or gained by switching trannies, It would probably be in the
30 to 60 hp range I guess!!

Oct 24, 2007 | 10:47 PM

abnormloffrd

Junior User

Joined: Dec 2006

Posts: 92

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From: washington the state

lower first gear in the tranny you would need 4.10:1 or 4.27:1 to equal the mechanical advantage of the manuals first gear and even 2 nd

Oct 24, 2007 | 10:50 PM

abnormloffrd

Junior User

Joined: Dec 2006

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From: washington the state

also did you reprogram the ecu for the new upgrades fancy parts do nothing if computer wont give the motor what it wants

Oct 25, 2007 | 12:33 AM

bigred66

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Tuned

Joined: Aug 2005

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Thanks for the reply's. I havent put a chip in it...yet, but its in the works. I also plan to put headers and a new y-pipe. I have yet to race him again and this time I'll do it on the outskirts of town so we can safely get up to speed. Whats the trans brake and how does it work? Where can I find one?