Transmission Question (LS vs GSR)
 

can someone explain the difference between an LS and a GS-R tranny? what are the benefits to going with a GS-R tranny over an LS tranny on lets say an LS-vtec swap. I know the gear ratios are different but what does that allow for? faster revving? smoother shifts at higher RPM? will an LS tranny handle shifts at 9000 rpm? is it worth the difference of lets say an extra 500-600 bucks to upgrade from an LS to GSR tranny? thanks in advanced for the help.

gsr tranny has shorter gears. quicker acceleration.

GSR trans as stated above has shorter gearing, and keeps you in "optimum" power band range in between shifts!

LS tranny was designed to keep b18a/b engines in there "optimum" power band range as well (non-vtec lower reving engines)

SIR/GSR/Type R transmissions were designed with shorter gear ratio's to stay within Vtec optimum Power Band Ranges.

I've seen time and time again, ppl switching to LS transmissions on high reving DOHC engines and regreting it.......... from slower acceleration, to falling out of VTEC between shifts.

Its almost like Honda Accord Transmission gearing, my brother previous h22a swap in His accord, he used his Accord Transmission on a h22 longblock, gearing was horrible, would fall out of VTEC in every gear!


Hope that provides a little bit of insight for you, all in all it really depends on what kind of power band your looking to have. LS transmissions are well suited for doing "High speed" hwy runs, but who really does that anymore? GSR transmission is really well suited for street/strip applications..good for everyday driving. Nothing against SIR/Type R transmission, as I daily drive with a Type R tranny. (if you dont mind shifting through 3 sometimes 4 gears between traffic lights that is :P ) lol


Travis

thanks a lot for the insight, so do you guys think it would be worth the extra 500 or 600 bucks to upgrade to the GSR/SIR/Type R tranny. the motor is gonna be a high revving vtec motor? shifts of up to 9000 at times.

I deffinately think so, if you can find one with LSD it would be even better! LSD trannies should be readily available if you can find at around $1000-1400 depending on who is selling. SIR/GSR/Type R LSD

SIR/Type R or bust

ok, so now that we've established that for my application LS is out of the question. Im left with 1 last question. What are the differences between a GSR and SIR transmission? and what should i go with, ideally i want to be able to rev faster, but at the same time i dont want to skip through my vtec like its non-existing. let me know what you guys think

Having 1st hand experience with both transmission (GSR vs SIR/Type R) The SIR/Type R transmission deffinately has shorter gearing and will allow you to accelerate faster, that being said, the con of having these short gear transmissions will also have you constantly shifting gears (atleast 3 gears stoplight to stoplight)

GSR transmission shares the same 1st gear as type R/SIR, has a slightly longer 2nd, 3rd 4th and 5th. ALL GSR SIR/Type R share 4.4 Final Drive. (unless your comparing JDM 4.7 FD Type R transmission)

GSR Transmission in 5th gear cruising on the Hwy at around 120km/h your RPM's are at roughly 3900/4000RPM.

SIR/Type R transmission same cruising speed 120 km/h your at 4500RPM. This is from my own personal experiences.

Personally, a GSR LSD transmission is a perfect Street Tranny to get! Sometimes driving around on the hwy with your car buzzing in every gear due to having a short gear ratio transmission is not always tollerable! LOL me I LOVE it, some passengers on the other hand........

again Trin, i thank you for your knowledge and your insight to my situation. i come away knowing a hell of a lot more than i did before..
respect for that

I personally really like the long gears of the LS tranny for a daily driver. (especially on the Hwy where 120km/h is only 3500rpm) With a nice N/A build-up or turbo it should match up really well and rev alot faster. If your Vtec is set at 5Krpm I don't see any problems with dropping out of Vtec.

But back to the original posters question "will an LS tranny handle shifts at 9000 rpm?" I'd like to know as well

my b16 tranny is at 4100 rpm in 5th at 120km/hr according to both crome and neptune datalogs, i don't trust what the tach says b/c there not always accurate. This is with SIR rims with 195/55/15's.
Setting vtec so low that you don't fall out of vtec w/a LS tranny isn't a good idea IMO...vtec too low with gears too long sucks.

I would rather set the Vtec point at the best spot for the engine and tune to make the most power. Nearly all N/A setups making over 200whp are set for 4800-5500rpm engagement.

and if ur using big cams making 200whp chances are your revving that to 8500-9500rpms so ur not gunna drop down to 5000rpms when u shift anyways.
My b16 with stage 2 cams had the smoothest torque curve and vtec crossover with vtec set to 6000rpm, but i wasn't making 200whp.

I agree with Zman, even on my turbo set up, my vtec is set to come in at 5800 RPM, torque curve is very smooth!

ok, well what im looking at is 230-245 WHP on a N/A built vtec motor will i have any problems with the LS? also its built to take shifts of up to 9000 rpm, i just want to know if the LS tranny will be able to handle that

i'd suggest installing a OEM, or aftermarket LSD into the LS tranny if that is what you want. cheaper LSD will cost around 3-$400, Quaffe will cost $1000 alone, plus install.

So you might be better off just getting a OEM LSD tranny, which would only cost around $1200 or less.

check out:

www.gearspeedinc.com

They can rebuild your transmission with carbon coated synchro's and install OEM or aftermarket LSD for a fairly good price

man i learned alot reading on this topic! great post! thx for hte info guys!

btw what is a gs-r hydro tranny? i hear it often also

its a transmission out of a GS-R integra 94 and up that had the hydrolic clutch. older modle GSRs had the cable clutch if im not mistaken

Thats gonna cost you at least 5K to get that much power N/A (probably more since a 1.8L would have to rev to 9500 rpm to make that much, so you're looking at a 2.0L+ block) so unless you specifically want to keep the LS tranny for some reason, I would just upgrade it. Or just ask your engine builder for their proffessional opinion ... :dunno:

Quickshift, my advice is go with a GSR/SIR with LSD or Type R tranny. If you're putting down the kind of power you say you will, you'll demolish non-LSD trannies over and over again real fast. You also asked the question about revving to 9 grand on an LS tranny. It all depends on how much hp you're putting down. LS trannies have been known to have really weak synchros, and high RPM's doesnt help that. I have had an LS tranny and an SIR tranny on the same VTEC motor, difference in acceleration is like night and day. Do yourself a favour, spend the extra couple bucks and grab a good tranny.

You won't get any motor below 2.0L to 245whp N/A and keeping the LS tranny with any N/A setup is stupid, cause guys with way less horsepower will be able to keep up with you easily.

Anyone know where in TO you can pick up a Quaife LSD for a fairly decent price?

Cheaper LSD's? anyone have any recomendations on a good one or any brands to completely stay away from?