Transmission Upgrades
Transmission Upgrades
Ok so ive been digging through the DIY section and i notice this was posted there
http://www.importperformancetrans.co...structions.pdf
has anyone actually performed this mod?
http://www.importperformancetrans.co...structions.pdf
has anyone actually performed this mod?
Because you're supercharged, I'd recommend doing it. Yes, it doesn't shift like a Lexus but a supercharged GS400 doesnt drive like one either. It will extend your tranny life with your supercharger...notice I said "extend" not save 
I had Boost Logic rebuild my tranny to hold more hp and they upgraded the valvebody as well.
I had Boost Logic rebuild my tranny to hold more hp and they upgraded the valvebody as well.
Because you're supercharged, I'd recommend doing it. Yes, it doesn't shift like a Lexus but a supercharged GS400 doesnt drive like one either. It will extend your tranny life with your supercharger...notice I said "extend" not save I had Boost Logic rebuild my tranny to hold more hp and they upgraded the valvebody as well.
I had Boost Logic rebuild my tranny to hold more hp and they upgraded the valvebody as well.I had the VB upgrade and after a little while you get used to it. Funny thing is I went from a VB upgrade to a stock VB and I hate the soft, slow, stock shift changes.
Because you're supercharged, I'd recommend doing it. Yes, it doesn't shift like a Lexus but a supercharged GS400 doesnt drive like one either. It will extend your tranny life with your supercharger...notice I said "extend" not save I had Boost Logic rebuild my tranny to hold more hp and they upgraded the valvebody as well.
I had Boost Logic rebuild my tranny to hold more hp and they upgraded the valvebody as well.
removed it awhile ago after the accident.
but maybe ill look into this. Shifting is rather slow when the GS400 is boosted maybe itll be a "temp" fix to constant redlining on first and second gear.
Trending Topics
Since you have a GS4...can't you control it from hitting the redline at WOT by shifting manually via e-shift buttons?
ClubLexus Stories
Celebrating Lexus & Toyota from Around the Globe
Lexus NX 350h: A Fuel-Sipping Secret Hot Hatch???
Michael S. Palmer
5 Best & 5 Worst Lexus Daily Drivers
Joe Kucinski
Top 5 Hottest Lexus & Toyotas in 2026 (Hardest To Buy)
Brett Foote
2026 Lexus IS 350 F Sport Review: The Last of Its Kind Still Rocks
Michael S. Palmer
Top 10 Most Confusing Things Lexus Has Ever Done!
Joe Kucinski
2026 Lexus ES Review: Lexus Re-Embraces Founding Principles
Michael S. Palmer
10 Lexus Bargains That are Cheaper Than a New Toyota RAV4
Joe Kucinski
8 Weirdest Things Lexus Has Ever Built
Verdad Gallardo
10 Lexus Designs That Have Aged Like Fine Wine
Verdad Gallardo
Yes/No.
The gs4 still has a delay.. especially when the engine is to fast for the transmission. Ive tried to shift it perfectly at redline a few times but it wouldnt go into third gear right away so it would bounce for a bit before kicking in.. the "fix" would be to let go of the throttle a bit to let the tranny shift. n ive been debating if i should sell my SC lol... but iono >_<.. if i dont get a GS4 again then yea ill sell.
The gs4 still has a delay.. especially when the engine is to fast for the transmission. Ive tried to shift it perfectly at redline a few times but it wouldnt go into third gear right away so it would bounce for a bit before kicking in.. the "fix" would be to let go of the throttle a bit to let the tranny shift. n ive been debating if i should sell my SC lol... but iono >_<.. if i dont get a GS4 again then yea ill sell.
Yes/No.
The gs4 still has a delay.. especially when the engine is to fast for the transmission. Ive tried to shift it perfectly at redline a few times but it wouldnt go into third gear right away so it would bounce for a bit before kicking in.. the "fix" would be to let go of the throttle a bit to let the tranny shift. n ive been debating if i should sell my SC lol... but iono >_<.. if i dont get a GS4 again then yea ill sell.
The gs4 still has a delay.. especially when the engine is to fast for the transmission. Ive tried to shift it perfectly at redline a few times but it wouldnt go into third gear right away so it would bounce for a bit before kicking in.. the "fix" would be to let go of the throttle a bit to let the tranny shift. n ive been debating if i should sell my SC lol... but iono >_<.. if i dont get a GS4 again then yea ill sell.
Cool! BTW, I know this sounds stupid (question) but I am not all that familiar with different SC setups and how they work. I notice that yours looks more like a turbo (or is it an actual turbo?), where does the SC belt hook on to? I am use to seeing a small transmission looking type of unit with an extension where a pully resides to which the belt goes around it and all the other accessories. How does your kit work? What type of kit is it originally? SRT, LMS, RMM etc.
I notice that yours looks more like a turbo (or is it an actual turbo?)
where does the SC belt hook on to?
. BTW the SC belt is pretty much a regular drive belt.. as long as its 6 rib and of the correct size. I went to Kragen n bought a gator one for $20 or so... kepted skipping ribs so i replaced it with the cheapest belt they have which was like $5.. works like a charm!!
I am use to seeing a small transmission looking type of unit with an extension where a pully resides to which the belt goes around it and all the other accessories.
How does your kit work?
What type of kit is it originally? SRT, LMS, RMM etc
