5th Gear in YS1 Transmission

ASSISTANCE Stock Engine-Bay Components
1

Hi,

I hope I am not beating a dead horse here with this post. I did do some searching on this site for my specific questions but ran into quite a few dead links.

I have a 1992 Acura Integra GSR with the YS1 Trans out of the car. I know it’s 5th gear ratio is 0.875. I am looking to put a longer gear in for highway cruising. (Currently out of car)

I also have another transmission that I believe to be a S1/YS1 US 90-93 Integra RS/LS/GS with a 5th gear ratio of 0.742. I don’t know exactly what trans this is but this is my guess. (Currently in car)
I tried using some online calculators to find out what transmission is in my car but my math skills seem to be off. haha

My car still has the original B17A1 and I am running 195/45/r16 tires on a 16x8 Wheel. Right now on the highway at 80mph I am at 4100/4200 @RPMS estimated.
Trying to figure out if the trans in my car currently would be a GSR or LS trans with this gearing.

I want to put a 5th gear (main & countershaft gears) in my original YS1 trans. I was wondering can I use an S80 US 94+ LS/GS/ with a 5th gear ratio of 0.714 in it, or will only a S1/YS1 US 90-93 Integra RS/LS/GS 5th gear work because it is a cable trans?

I found a post where someone said “Acura 94-01 LS counterhaft 5th gear. Acura 94-01 LS mainshaft 5th gear. Fits right in 94-01 hydro and 92-93 YS1 cable transmissions.”
I’d just like to confirm before I make this purchase.
I understand that the YS1 has a 4.4 final drive and this will not solve everything but I would like to drop the RPM’s some for highway driving and keep my original trans in the car.

Thanks in advance

Reference Links
http://honda-tech.com/honda-crx-ef-civic-1988-1991-3/faq-how-ls-5th-gear-install-guide-jdm-b16-s1-555929/
http://www.ff-squad.com/tech/temp/Bgears.htm
http://honda-tech.com/transmission-drivetrain-127/ls-5th-gear-b16-transmission-2879988/
http://www.summitracing.com/expertadviceandnews/calcsandtools/gear-ratio-calculator
https://tiresize.com/calculator/

2

The YS1 essentially has hydro internals. I run a DC2 GSR 5th in my YS1. It’s not as long as the LS 5th but still a huge improvement over the stock YS1 5th ratio.

3

I posted the same question here. 5th Gear in YS1 Transmission - Honda-Tech - Honda Forum Discussion

I actually found a DC2 GSR 5th on Ebay purchased it and then it turned out to be a LS. Still on the lookout for some 5th gears if anyone on here has some to sell, particularly (.787 or .742) may do .714 though.

4

Good discussion on HT. I am very happy with the DC Gsr 5th, I was driving a lot of highway when I put that trans together and it made cruising a lot nicer. I wasn’t concerned about lack of torque as I have an LS/Vtec in my DB2 and it is now boosted as well.

5

I am looking for a 0.875 B17 5th gear like the one that you do not want, and would be willing to send you a 5th gearset in exchange for yours. I sent you a PM on Honda-Tech.