Dyno HP #'s, 3.55's vs 3.07's

VIPERnXr4ti

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Re: Dyno HP #\'s, 3.55\'s vs 3.07\'s

i think the fact there is no difference in 1/4 times is because it is harder to stick a launch with the shorter gears...i know on my car if I were to step up to 3.73's right now I would probably cut a half a second off my 1/4 time...


Anthony
 

Snakester

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Re: Dyno HP #\'s, 3.55\'s vs 3.07\'s

It's definitely a trade-off with the downsides of shorter gearing being more shifts and lost traction. But the key is that the shorter gears essentially compress the acceleration, with torque multiplication helping matters.

I believe that with sticky tires to equalize the traction issue, that the shorter geared car would be quicker.

There are two points. One is if you are shifting at say 5800 RPM, the shorter geared car is going to put you at a higher RPM point when shifting into the next gear. And this happens in every gear but 1st.

Also if you have 3.07 gears and are essentially on the low end of your powerband, there is a long pull before you get on the power. Whereas with the shorter gears, you are closer most of the time to your power peak in each gear, when you take into account the longer span of acceleration in each gear.

For me, there was always a bit of a hole in my acceleration at the start of each gear. And that hole was filled with the gears. Of course you can drop down a gear with the 3.07s to get closer to your power peak. But with the shorter gears you are likely there already.

Personally I think that the power of a modded Viper is a bit much for 3.73 or shorter gears when using stock tires.
but 3.55s are a nice mid-point, having a noticable added pull in each gear (for me).

It's essentially the same as if you kept the 3.07s and just narrowed the ratios in each gear. And I can especially feel the difference in 5th and 6th gears on the freeway.

If you were driving at 70MPH in 6th, cruising along at around 1450RPM, and decide that you want to accelerate, you are out of luck. With the 3.55 gears you are turning around 1600RPM and it actually accelerates somewhat.
The difference is even better in 5th gear at freeway speeds.
 

joe117

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Re: Dyno HP #\'s, 3.55\'s vs 3.07\'s

When you had your 3.08 you could drive at 70mph at 1450rpm in sixth gear?
 

Big Medicine

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Re: Dyno HP #\'s, 3.55\'s vs 3.07\'s

Joe I've been with you for a while on this one, but I think you should just give up. Sometimes it's not worth it. You've been fairly unambiguous and illustrative.
 

ViperRichRT10

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Re: Dyno HP #\'s, 3.55\'s vs 3.07\'s

Well, I went and did it. I put in the 3.55 gears and they are allot of fun!

Rich
 

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