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Thread: P11/B15 Gears

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Posts: 141-150 of 214
2014-10-03 19:19:04
Have you guys figured out what ratio you would like to see? This is stock with a 24.5" Tire

RS5F70V (2.0L) 4.1 FD

3rd Gear 1.286 118MPH
4th Gear 0.926 155MPH

MFactory® Competition Products - Gear Calculator
2014-10-03 19:23:34
From MFactory. I'm all for the most expensive steel and straight cut since I've dumped so much damn money into the car. Don't want to be held back by a tranny
Originally Posted by MFactory
650hp+ would need SAE9310 steel, which is the most expensive.

For the tooth profile, depending on the ratio, this will determine the maximum root width of each tooth, and which would be the stronger profile to use (straight cut or semi-helical).

If you could post up on the thread and see what the general consensus would be on the ratios. You can use our gear calculator to help: [url]www.teammfactory.com/gear-calculator[/url]


Originally Posted by Dave_SR20
To cover a wider range I would go for 650HP +. If we can get a little more MPH out of our 3rd and 4 th that would be great. In terms or straight but or slanted thats up to you based on your expertise
Last edited by Dave_SR20 on 2014-10-03 at 19-24-38.
2014-10-03 21:21:31
I'm with Dave on the steel option.
2014-10-04 11:18:49
Bump. LMK if we're going for a longer 3rd and 4th. If so what ratio
2014-10-04 12:17:19
I am no expert at gearing but a longer 3rd and 4th would be optimal.
2014-10-04 12:25:08
Neither am I. @MFactory can you recommend ratio for a drag application? See below for our factory ratio. Base it on a 24.5" Tire

RS5F70V (2.0L) FD 4.176
3.333 1st
1.955 2nd
1.286 3rd
0.926 4th
0.733 5th
2014-10-04 13:38:54
Whats the max rpm, and what sort of trap speed you guys after?
2014-10-04 16:35:26
Here is a side by side on a 32V vs a 70V. I would love to see 150mph trap speed. @MFactory maybe you can answer this question. Why with the stock circulations we don't see close to those numbers on 4th but it seems that we're redlining it?

2014-10-04 18:35:51
Believe it or not, the stock 70V ratios with 4.176 are actually the perfect ratios, with a 151mph top speed in 4th gear. 3rd Gear tops out at 109mph. Once the tires heat up and expand, this will increase by a few mph.

The figures show the maximum potential in each gear, however, it does not take into consideration drag coefficient, power, traction nor driver skill. These factors combined will determine what you will eventually max out at. If you are not currently able to reach these speeds (but you do have sufficient traction), then making the gears longer will only make you accelerate slower.
2014-10-04 18:54:24
Based on that i'm ok with stock ratio. Everyone else?
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