Will a S9B gearbox fit a b16a2


YUNUS coventry

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Hi I got. Gear box of a civic vtis I want to now is it just a straight swop and what gains will I get accept the LSD Thanx
 


Jimbo

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Yes it's a straight bolt on, as are all B series gearboxes! I wouldn't recommend using the S9B as the gear ratio is very long, with the B16 not having much torque out the box you want a S80 with a 4.7FD to optimise what you have.

You will notice a big difference with an LSD although the LSD is not as track orientated as the S80 and S4C diffs!

My advice would be save your money and get one of the previous mentioned boxes ;)
 

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Darragh

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Yes it's a straight bolt on, as are all B series gearboxes! I wouldn't recommend using the S9B as the gear ratio is very long, with the B16 not having much torque out the box you want a S80 with a 4.7FD to optimise what you have.
What this man said especially if its a 96spec s80 or S4C with a 4.785/4.928 Final Drive

The s9b box has really long overall ratios so torque to the ground numbers will be less than your own box .
 




Kozy

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S9B is a torsion LSD and the S80/S4C use a helical LSD.
Torsen/Helical are the same thing aren't they? Torsen is a brand, helical is the type of diff. I'm not 100% certain but the S9B might be viscous?

Even the S80 box might not be best for the B16, the 3/4/5 ratios are longer and you'll dropping out of the power band, despite the overall ratios being lower.

Get an EK9 S4C, it's the best suited out of-the-box er, box for the B16.
 

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dhdavectr

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Torsen = TORque SENsitive

the viscous unit you are on about is really rare and it's definately not in the s9b box.

S4c is a great choice as it's the same ratios as the vti anyway.
 


Darragh

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Helical uses the same principle of the torsen except it uses different gearing hence the name Helical , both are TORque-SENsitive tho.
 


Kozy

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Yes, techincally true, but Torsen is a brand, not a type of diff.

The ONLY Official TORSEN Home Page!

Whereas helical is a type of diff, not a brand.

Only semantics, but one that should be cleared up non the less. :D
 

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Darragh

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Yes, techincally true, but Torsen is a brand, not a type of diff.

The ONLY Official TORSEN Home Page!

Whereas helical is a type of diff, not a brand.

Only semantics, but one that should be cleared up non the less. :D
Yeah totally true i dont disagree :nice: , like the helical (TORSEN type) is designed and patented by Quaife I believe. Just the name sticks sometimes like ''bendix gear'' on a starter should be a pinion drive gear and a ''hoover'' should be a vacuum cleaner lol :)
 


Kozy

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Yes guess so.

So what is the difference between the Type R diffs and the one in the S9B then? Just not as aggressive?
 


Darragh

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I guess its down to the torque bias , whether its higher or lower than the helical I dont know
 


Kozy

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Hang on I thought they were all helicals? I'm confuzzled now.
 


lance

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what about a s4c into a b18c4? would that be better than having an s80?
 


Darragh

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From what ive read they have the torsen non-helical type? I may be wrong , ive no first hand experience with the s9b box.
 


Darragh

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Just checked the part number for the s9b box and it turns out its the same helical lsd !

41200-P80-003
 


Kozy

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Same as the S4C/S80 then? Maybe the reason people think they are weaker is that fact that by virtue of them being torque sensing, and the S9B having longer gearing (so less torque at the wheels) they feel less agressive than the S4C/S80 boxes?

From what ive read they have the torsen non-helical type?
But isn't this back to whole Torsen=helical thing? I.e. 'Torsens' (the brand) are helicals, but not all helicals are Torsens? :nono:
 


Darragh

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Yeah same as the ek9/dc2 helical lsd. The gear ratios should not effect the operation of it , because the torque bias ratio is the same , you should still see the same effects .

Ok ok call them Automatic Torque Biasing differentials :D
 


Kozy

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Yeah same as the ek9/dc2 helical lsd. The gear ratios should not effect the operation of it , because the torque bias ratio is the same , you should still see the same effects .
My Quaife feels more aggressive at 7k than it does at 3k, I was always assuming this was because more torque at the wheels (say 120lbft at 7k vs 100lbft at 3k) got a bigger reaction out of the diff, so the gear ratios should have the same effect...

Assume the bias ratio is 5:1...

100lbft though a 2.105 x 4.4 ratio (S4C second gear) is 926lbft at the wheels, which is then 771:154 or 617lbft split.

120lbft though a 2.105 x 4.4 ratio (S4C second gear) is 1111lbft at the wheels, which is then 925:185 or 740lbft split.

vs

120lbft through 1.90 x 4.266 ratio (S9B second gear) is 972lbft at the wheels, which is 810:162 or 648lbft split.

Same diff will feel more aggressive though the S4C no?
 


Darragh

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No your totally right Kozy ! I misread your post , I was referring to its operation , the split would still be the same ratio but engine torque output and gearbox torque multiplication will effect its torque .

But theres obvious limitations like axle speed and wheel traction will effect it. I really need to dig up my old notes on this :blinx:
 


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