3.80 final drive
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Suzuka Master
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From: 633 Stag Trail Rd
3.80 final drive
Thanks to NvrDwn posting this info on the *other* forum, it appears 6MT owners are in luck!
http://tbmotorworx.com/tb-motorworx/final-drive/
Should be good for a 2-3/10 and a maybe 2-3 mph. Gas mileage will suffer a little, but it should make the car feel a little more torquey, which it needs.
http://tbmotorworx.com/tb-motorworx/final-drive/
Should be good for a 2-3/10 and a maybe 2-3 mph. Gas mileage will suffer a little, but it should make the car feel a little more torquey, which it needs.
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Suzuka Master
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From: 633 Stag Trail Rd
Yeah, I don't buy the half second. ESPECIALLY on a 9/10 second car. Guys go from 2.73-3.73 in their F-Bodies and are lucky to shave 5/10. Back in the day, I went from 3.23 or 3.42 (can't remember) to 4.10. Never got any slips, but it was noticeable for sure. Even though this is overpriced, the performance ratio per dollar has the potential to be relatively strong.
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It might be slightly off topic, but is it just me, or is it odd how different the transmission ratios are between the 6MT and the Auto. The auto's final drive is 4.31. I guess I always thought it odd of Honda to use such high numerical gears in the 6MT transmission and a relatively low final drive.
That is a huge loss of MPH in 4th too. It doesn't make much difference in cruise RPM in 6th, ~ 400 rpms, but to go from 125 in 4th to 108? No thanks.
anx - when I went from 2.73 to 3.42s in my camaro, I shaved a good 6/10ths off. A 2.73 auto is a giant turd on the track. It was much more fun on the highway, but an auto is boring to me in all regards.
That is a huge loss of MPH in 4th too. It doesn't make much difference in cruise RPM in 6th, ~ 400 rpms, but to go from 125 in 4th to 108? No thanks.
anx - when I went from 2.73 to 3.42s in my camaro, I shaved a good 6/10ths off. A 2.73 auto is a giant turd on the track. It was much more fun on the highway, but an auto is boring to me in all regards.
Traction should become an issue
The final drive that Honda has chosen to use over the years with the 6 speed tranny's has depended on the rim/tire size. It would make sense to go 18's. I'm guessing this will be a 3-4 MPH higher readings, top speed in certain gears will change, MPG will drop, and depends if this set up benefits the 3.2L, 3.5L, or the 3.2 with the 3.7 conversion. Lots of questions still in the air. Like how much will you be shifting xxxx rpms less to simulate a 1-2 redline shift? Could be 500-1300 in that range?
The final drive that Honda has chosen to use over the years with the 6 speed tranny's has depended on the rim/tire size. It would make sense to go 18's. I'm guessing this will be a 3-4 MPH higher readings, top speed in certain gears will change, MPG will drop, and depends if this set up benefits the 3.2L, 3.5L, or the 3.2 with the 3.7 conversion. Lots of questions still in the air. Like how much will you be shifting xxxx rpms less to simulate a 1-2 redline shift? Could be 500-1300 in that range?
Beware....do not read any further if you are bored by analytics: 
Stock 6800 Redline with 215/50/17 (almost identical to 235/45/17 for the TL)
Stock FD / TB-M 3.8
1st / 42 / 36
2nd / 63 / 55
3rd / 92 / 80
4th / 125 / 108
5th / 160 / 138
6th / 204 / 176
7200 w/Hondata
Stock FD / TB-M 3.8
1st / 45 / 38
2nd / 67 / 58
3rd / 98 / 84
4th / 133 / 115
5th / 169 / 146
6th / 216 / 186

For those of us looking to improve our 1/4 mile ET/traps, this is single-handedly the best mod out. Guaranteed a bone stock car with no mods other than this FD will run high 13s easy. I agree with ANX in terms of the 2-3 tenths & potentially 2-3mph in the 1/4. I even think full bolt on cars will see more like a 3-4 tenth difference.
Currently, most of us are at the bottom of 4th gear when crossing the traps, which is not ideal at all. With 4th ending near 108mph @6800 RPM, this is a perfect setup for the 1/4. And cruising at 65mph is @ 2500RPM whereas stock is 2200. Hondata is key here as well with an increased redline that would allow us to stretch the gears a bit further.
I witnessed 1st hand the difference between the 4.3 FD and 4.7 FD on the RSX. On the street from 40-130 the difference was about 3-4 cars. Both cars had near identical mods, the same tuner and made within 2hp/tq of each other on the same dyno. Both cars with good drivers. This is a HUGE step in the right direction for the J series!

Stock 6800 Redline with 215/50/17 (almost identical to 235/45/17 for the TL)
Stock FD / TB-M 3.8
1st / 42 / 36
2nd / 63 / 55
3rd / 92 / 80
4th / 125 / 108
5th / 160 / 138
6th / 204 / 176
7200 w/Hondata
Stock FD / TB-M 3.8
1st / 45 / 38
2nd / 67 / 58
3rd / 98 / 84
4th / 133 / 115
5th / 169 / 146
6th / 216 / 186
For those of us looking to improve our 1/4 mile ET/traps, this is single-handedly the best mod out. Guaranteed a bone stock car with no mods other than this FD will run high 13s easy. I agree with ANX in terms of the 2-3 tenths & potentially 2-3mph in the 1/4. I even think full bolt on cars will see more like a 3-4 tenth difference.
Currently, most of us are at the bottom of 4th gear when crossing the traps, which is not ideal at all. With 4th ending near 108mph @6800 RPM, this is a perfect setup for the 1/4. And cruising at 65mph is @ 2500RPM whereas stock is 2200. Hondata is key here as well with an increased redline that would allow us to stretch the gears a bit further.
I witnessed 1st hand the difference between the 4.3 FD and 4.7 FD on the RSX. On the street from 40-130 the difference was about 3-4 cars. Both cars had near identical mods, the same tuner and made within 2hp/tq of each other on the same dyno. Both cars with good drivers. This is a HUGE step in the right direction for the J series!
Thread Starter
Suzuka Master
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From: 633 Stag Trail Rd
Do it Sonnick. As long as you're already in there, what's another 1200? (not sure what starting at $1199 means though. 1200 is still cheaper than cams and head work. Between the gears and the FP, you should be able to sling that bitch down the track at 12.90-13.00 @ 108-109.
So now all you need is head work, cams and injectors. I forsee 320+
If jiga21 can hit 305 on the stock intake manifold, you can easily get that 320+
Then take some extra weight out and you'll run mid 12's 110+ all day everyday.
I have the SI with the FD2 final drive and the RSX 5th gear... this dramatically changed the course of the trap, yes. But if you had a K24/20, it would not be of any benefit... why that mod was only for the 2.0L. Why the question sits to those with the 3.2/3.7 mod. The added torque added to the torqueless SI, gave the car a good punch in the lower gear because of the new teeths added.
If I have the cash right now, I'd be testing along side... but I will just be disspointed.
If I have the cash right now, I'd be testing along side... but I will just be disspointed.
I've had it for a few weeks. I didn't want to say anything until I had it installed, but I saw the perfect opportunity when Adam said that lol. And I SUCK at keeping my own car 'secrets' hidden lmao.
I just need to find a trusted place to install it. Preferably a transmission shop that's done this sort of thing.
I just need to find a trusted place to install it. Preferably a transmission shop that's done this sort of thing.
Thread Starter
Suzuka Master
iTrader: (2)
Joined: Feb 2008
Posts: 5,020
Likes: 933
From: 633 Stag Trail Rd
I've had it for a few weeks. I didn't want to say anything until I had it installed, but I saw the perfect opportunity when Adam said that lol. And I SUCK at keeping my own car 'secrets' hidden lmao.
I just need to find a trusted place to install it. Preferably a transmission shop that's done this sort of thing.
I just need to find a trusted place to install it. Preferably a transmission shop that's done this sort of thing.
It makes them shorter. The Rev limiter was Sonnick saying what it would look like with the limiter raised using hondata. It does throw the speedo off
Yea it's $1199 plus shipping. I first saw it on their website/FB before it was posted on the forums.
I got a quote from a shop about 3 hours away (sigh) for $250, which isn't bad at all. Also TB Motorworx said they would do it for $250, but they're in Cali ha. I believe King Motorsports charges $200 labor, which it says on their website.
Bouncer: What do you mean 4-4.5k @ 60-65mph? Our cars are nowhere near that, even with the 3.8. Cruising @65 is 2500 and 80 is 3000.
I got a quote from a shop about 3 hours away (sigh) for $250, which isn't bad at all. Also TB Motorworx said they would do it for $250, but they're in Cali ha. I believe King Motorsports charges $200 labor, which it says on their website.
Bouncer: What do you mean 4-4.5k @ 60-65mph? Our cars are nowhere near that, even with the 3.8. Cruising @65 is 2500 and 80 is 3000.
Last edited by Sonnick; May 16, 2014 at 10:09 AM.
Thread Starter
Suzuka Master
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From: 633 Stag Trail Rd
Those prices are with the transmission out of the car though. Probably looking at closer to 700-800 drive in/drive out. Then factor in new shims, seals and pinion bearings and you're over two grand total.
Looking at those Honda gear set prices on King's website made me cry. They're like half the price of this one.
Looking at those Honda gear set prices on King's website made me cry. They're like half the price of this one.
Video of a before and after or document would be good info for us. I'm sure we'll be seeing more videos from either way.
The integra with a J-series shaved .5 on the light chassis with slicks... This questions the chassis with Accord swaps, Prelude swaps, and TL chassis. How much will it shave on a heavier body? See if anyone on this forum will bite.
I've had it for a few weeks. I didn't want to say anything until I had it installed, but I saw the perfect opportunity when Adam said that lol. And I SUCK at keeping my own car 'secrets' hidden lmao.
I just need to find a trusted place to install it. Preferably a transmission shop that's done this sort of thing.
I just need to find a trusted place to install it. Preferably a transmission shop that's done this sort of thing.
Wait what... you kept this secret from me... But then again you will get to the 12s before i do.
Thank you Sonnick for taking the plunge on this one! Very interested to see the results in the J-Series.
What is up with all the holes in the ring gear? I know my integra's ring gear does not look like that.
What is up with all the holes in the ring gear? I know my integra's ring gear does not look like that.
This is an awesome mod.
For those saying it will hurt mpg, it shouldn't make a difference in the city, none at all. On the freeway it might make a small difference.
It will make all gear ratios effectively lower and closer together. This would be good for both drag racing and most road racing and on the street too. It's even possible to get longer clutch life.
Just to clarify, gears will be shorter or lower, not taller or higher. It's no use comparing this mod to a domestic V8 with gears. The lower torque/higher revving Honda engines are more sensitive to gear ratio. My turbo car actually slows down when you go from stock 3.42s to 3.73s unless you go with larger tires to retain the same overall ratio.
I think a gear that allows up to 108mph traps near peak power is perfect for 90% of the TLs out there. There would be less worry of falling out of vtec not that falling out if vtec is the end of the world as long as the crossover point is setup right. This is a really optimized setup for what most TLs trap at.
This mod can be more beneficial on our heavier, lower power cars than a light high power car.
I will say that this probably won't work as well with turbo TLs. The turbo engines like the higher load of longer gears. It allows quicker spool and the additional torque will have no issue pulling the longer gears.
For those saying it will hurt mpg, it shouldn't make a difference in the city, none at all. On the freeway it might make a small difference.
It will make all gear ratios effectively lower and closer together. This would be good for both drag racing and most road racing and on the street too. It's even possible to get longer clutch life.
Just to clarify, gears will be shorter or lower, not taller or higher. It's no use comparing this mod to a domestic V8 with gears. The lower torque/higher revving Honda engines are more sensitive to gear ratio. My turbo car actually slows down when you go from stock 3.42s to 3.73s unless you go with larger tires to retain the same overall ratio.
I think a gear that allows up to 108mph traps near peak power is perfect for 90% of the TLs out there. There would be less worry of falling out of vtec not that falling out if vtec is the end of the world as long as the crossover point is setup right. This is a really optimized setup for what most TLs trap at.
This mod can be more beneficial on our heavier, lower power cars than a light high power car.
I will say that this probably won't work as well with turbo TLs. The turbo engines like the higher load of longer gears. It allows quicker spool and the additional torque will have no issue pulling the longer gears.
Not sure what they usually look like, but from what I heard they modify the stock pinion to come up with the 3.80. Not sure how because I don't know what it involves, but I would trust it. They send them out to Liberty Gears to be modified as far as I know, considering that's the name that was on the box it came in.







