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Thread: B15 Vs SR16VE Vs SER Gear Box Comparison For NA

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Posts: 61-70 of 77
2011-02-11 20:58:18
Originally Posted by THOR
What effect will changing ur 4.1 fd to 4.38 have on ones 1/4 mile time.... and will this box still finish the #uarter in 3rd gear...?

use the mfactory gear calculator and work out what speed you will be doing in 3rd, then you'll know

as regarding the 5.0 final drive, the casing will have to be shaven to to fit it in thus weakening the case

i was onto vahur about gettin one but because i could get enough people to fill the order it didnt happen but ended up gettin the 4.785 mfactory one instead for my sr16ve box

if was doing it again i would just get custom gears cut coz the gears in the sr16ve arent meant for 1/4 mile
2011-02-16 04:14:49
Miko, Wouldn't an SR16 box w/ 4.176 FD and a P12 6th gear replacing the 5th gear be the best for those with a DD big bore VE? It would look like this:

1st 3.333
2nd 1.955
3rd 1.333
4th 0.975
5th 0.673

This way, the SR16 is made taller in the lower gears to prevent wheelspin while also maximizing economy in 5th gear. 3rd and 4th would still be pretty quick but wheelspin shouldn't be a problem by then. My only question is, can a P12 6th gear replace an SR16 5th gear? If it can, I calculate that @ 70mph in 5th gear, you would be below 2900rpm. Is this right? If not, can we use a b15 6th gear?

In your "hardcore VE" thread you mention that youre going with an SE-R gear box with the 4.058 G20 FD on a 2.3L VE, but wouldn't the acceleration be less than optimal? Economy would be phenomenal but I feel 2nd and 3rd wouldn't be quick enough, unless this is just a chill DD. VVL wouldn't stay open when shifting at redline would it? IDK, I'm still a noob at this. Maybe you can't just throw gears here and there. Very interesting tho.

2011-02-16 14:45:37
Whats the point of making more power and then lowerig power with longer gears?
2011-02-16 18:56:43
You want to cross the 1/4 mile in third gear I think.
2011-02-16 23:59:49
Plus more power introduces more wheelspin, especially in 1st. I would think 1st gear would be useless on street slicks on a big bore VE unless the gear is longer.
2011-02-17 00:36:20
You want to cross the 1/4 mile at your peak power. Idealy it would be 4th or 5th but sometimes our gears are to long and we just aim for the top of 3rd instead.

My car for example is running the de box (because the gear spacing is better then sr16) with the 4.785 fd and shorter slicks to cross at almost peak power at 4th gear at 116.

Just go in the calculator and play with slick size and final drives. Either run a taller slick and hit the top of 3rd or or make more power run a shorter slick and get into 4th.
2011-02-17 02:38:36
^^^^^ ugh all possibilities look awful for a 103-106mph car I hate nissan's gearing
2011-02-17 02:53:49
std de gear box with 23.5in slicks... but as long as your making good power up high. Hold 3rd
2011-02-17 04:01:24
I'm making 196 -147tq 3" exhaust is going in tomorrow probably so I expect close to 200whp. full weight car with 260lbs driver I have an sr16 box and its reading 95-96mph on the dyno @ 8500-8600rpm I expect at least 102mph

I'm looking at that 4.78 fd with doubt
Last edited by morris on 2011-02-17 at 04-06-06.
2011-02-17 09:15:18
Or custom 4th gear and smaller tires.
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