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Old 10-17-2012, 01:16 PM
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Originally Posted by vinniekq2 View Post
AP72,you are correct"They aren't related directly"

most cars and trucks have multi gear transmissions,to say a car with a flat tappet hydraulic cam "needs" 4.30 or 4.56 gears?
Im trying not to correct or call out anyone,but,,,,,,,?lets think about gear choices and applications.I use 3.5 gears and my cam is 256/264@50 with valve lift over 600,is my gear choice wrong?
Not of you are running bonneville. Or have a very high horsepower to weight ratio.
On the street you will have sluggish initial acceleration with a big cam and no gear. ( assuming typical car wight and HP to weight ratio).
You will also be "on the converter" for a long time when you rug it.
Inefficient, creates converter heat. Long wait for the power band to hit.
Bad choice when a high stall converter is used (unless the power to weight ratio is very high)

Unless your car is very light weight or your don't care about acceleration.

Of course if you have no tires traction It won't matter much.

You average camaro malibu muscle car #3200-3600# with a 350 and a 256 cam and 28" tall tires wiill want a 4.30 to 4.56 gear It wil alos want 10:1 to 10.5:1 cr (for pump gas)( if you want strong acceleration.)
The motor will want to cruise at 60MPH at around 3200-3400rpm in Drive (1:1)

At the track you would be way under geared with 3.50:1 gears. Your ET will be 4 to 8 th's slower than what It could be with the right gears.

You can run what ever gear you want in your car. Its your car. But don't expect stong acceleration performance with a big cammed 350 and hiway gears in a typical weight car or even worse in a heavy truck) and a stock low stall converter. All the torque power will be at higher rpm ...very high vehicle speed. Initial Acceleration will be lame untill the rpm gets up to where
the cam makes power. 3000+++ 3500++rpm for a racey 256 cam.
Unless you got 5 or 6 transmission speeds (with a low 1st and 2nd ratio) to work with. Not the typical 3 forward gears and a 2.5:1 first gear as in most cars.
If you want to optimize it to break the land speed record thats a different thing.

Last edited by F-BIRD'88; 10-17-2012 at 01:44 PM.
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