Hello,
I am about to rebuild my JDM YS1 tranny and want to add a higher 5th gear from an LS tranny. However, my search on HT has left me confused as to what versions and years of LS trannys I can get the 5th gearset from. Some posts seemed to indicate that I must use a 5th gearset from a 90-93 LS but that there is a difference between the 90-91 and 92-93. If so, does a JDM YS1 require the 90-91 or 92-93 LS gearset, or will either fit?

Some other posts indicated that the LS gears from a hydraulic tranny can be used. Can just the 5th gears be swapped or does this require swapping the complete main and counter shafts assemblies?

Thanks

 

Hey man I did it in a j1 tranny and I had to use 90-91 ls 5th gearsets. & good luck finding them too
but it's totally worth it. i'm now in a dseries si tranny and i miss my 90mph 4krpm

 

you can use a YS1 LS 5th gear set, or a hydro LS 5th gear set. when i set a set, it means one gear from the countershaft and another gear from the mainshaft. there are two parts, to every gear in a honda transmission. from my experience, the hydro ls 5th gear, will give you the lowest rpms while cruseing on the highway. for the people with the y1/j1/s1 jdm transmissions, they need to source a 90 ls transmission to get the 5th gear from. the dealers don't sell those parts anymore, so you need to get a usdm s1 1990 integra ls transmission. good luck

 

Thank You.
It all makes sense to me now.