Black_IS300

Just wanted to ask you guys about torque converters because I notice quite a few people have them on their GS's. From what I understand your car will rev up higher from a stop before it actually kicks in gear. Is this right? Ive also heard you can really launch hard off the line... what about when you want to drive normal. Can you still take off from a stop smoothly? Does it change the way your car shifts too or is it all about the launch? Any input would be great

thanks

RacingAristo

When I have RMM installed the TC, I immediately felt the difference when I first step on the gas pedal. The aftermarket TC allows the car to rev higher at the beginning. It took me awhile to get used to it and learn to drive it normally.

I haved this TC installed long time ago once I got this car so I forgot how it was driving on the freeway with bone-stock. Sorry I couldn't help you on that, whitediamond.

Black_IS300

but can you still take off smoothly? If a cop is next to me am I going to be able to not launch off the line?

RacingAristo

yes, you can.

JacobT

Black,

A converter is a converter. It transfers the torque from engine to drive shaft. The aftermarket TC has a higher stall speed and smaller diameter. so it light weight than the stock one. When you push it, the stock TC start moving the car at around 1k rpm while the aftermarket one do the same thing but at slowly ramp up, at around 3k rpm, you feel the thrust that push you all the way out.

Due to the higher slippage rate, it totally changes the gear shift point. At 70 mph highway spped in lockup mode, if you push down the padel, it will down shift 1 or 2 gears immediately depends on how hard you push it. Don't worry, you can drive it with TC in absolute normal way. But when you push it, you know it's there to make the difference. The TC will get you hooked, I took it out for about 4 months and put the stock one back in, I just couldn't justify for the way that the stock TC drives. So after 4 months of dog acceleration, I put the TC back in and the GS was back tio life again:eek:

Mean Gene

Guys - From what I've gathered in 25+ years of auto customizing & drag racing, the torque converter has got to be THE most misunderstood piece of equipment in a car! It's not that much of a mystery. It's simply a viscous coupling between the engine & transmission using the fluid ( under pressure ) in place of a mechanical clutch/pressure plate/flywheel assembly in a manual tranny. The stall speed is similar to slipping the clutch on a manual as well. A stall speed of 3000 rpm DOES NOT mean the car won't move until the engine is turning 3k. It is the approximate rpm at which the converter is fully engaged ( or "locked up" in the newer trannys ) - like a mechanical clutch. Imagine driving a standard tranny but w/o having to row the gears. The T/C will slip & allow the engine to reach it's powerband sooner. How much depends on the amount of throttle pressure U've applied. Floor it & it will "flash" to the stall speed it's designed for ( 3k, in our example ). This is right where the GS4 4.0 begins to make power so acceleration will be maxed out. Drive like my wife ( & her size 6 foot! ) & U'll barely notice it's there - drives almost like stock but with a SLIGHT bit of extra slippage which U'll get used to ( like RA said ). Don't worry about spinning the wheels unless U floor it from idle!! As far as gains elsewhere than off-line, once it hits it's stall speed ( 3k ), it's only advantage is that aftermarket T/C's R built stronger than factory ones & will handle more power ( like a S/C; nitrous or other performance mods ). Downsides - extra slippage generates extra heat ( the #1 enemy of ALL trannies! ). Fight this with a tranny cooler if U drive hard & live in a hot climate - it's not 100% necessary even there but will help. Lastly, U may notice a slight loss of highway mpg due to that aforementioned slippage. However, if U drive above the locked-up stall speed rpm, it will be minimal if at all noticeable. I pulled down 22 mpg cruising at 85-90 mph which was a cruising rpm of 3200 - only got 24 highway mpg before changing the T/C & rear gears ( which R responsible for most of the mpg loss, IMO ). Sorry this is such a long post but I hope it clears up a great deal of confusion about an excellent performance modification!

Gs400TRD

Dang Gene,
Almost as long as I have been alive Gramps hehehe
Seriously, I am concerned about screwing up the transmission. I really want to keep this car past 130k miles (at least for 4 more years. until I am out of grad school). Plus I have to purchase a new truck after the recent Flooding incident. (And the "It better be at least a 2 carat Diamond Solitaire" fund can’t be touched. )
Where can I get a transmission cooler for the GS and how do I install it? Is it easy? Expensive? Similar to the coolers on available on trucks? Downside? Thanks.
hope I didn’t question you to death.

JacobT,
Since you are nearby (Austin) where did you get your TC installed? I am going to probably go with the Sways first before the l-tuned so I can probably get both done. What was the cost of labor? Thanks.

JacobT

There're several shops here in town can do the TC install. The price range from $360 - $450. The cooler is easy, you need to find the place in front of the radiator to install the cooler then re-route the existing tranny cooling lines to this new unit. The factory cooling lines are connect to the radiator at the bottom. I got a quote for $160 installed, parts and labor.

Black_IS300

Thanks for all the info! So in other words this is something I should get for my car if I dont trade it in for the manual

Mean Gene

mG - What can I say? I'm a well-preserved fossil!! About the cooler - Mo can hook ya up with one as he sold me one when I got my T/C from him. Just any slim-line model will help out - think mine's from EZ Go. If U want to hide it from prying eyes ( service writers ), get some BBQ grill black paint & spray it before installation. Not only will that help it blend into the radiator, the black coloring will help dissipate heat. Like jacob said - run the auxillary cooler in addition to the factory setup. Hope the Houston flooding didn't getcha? I left our office on Dallas Street Wednesday ( in the company car, thank goodness! ) heading offshore so I missed it.

Gs400TRD

Thanks for the info.
Downtown Houston is still a mess, so is the Medical Center.
The flooding did not get my Lex, but wiped out my Tacoma that was left at "The Parking Spot" Still waiting for insurance. But I figure I am going to get a Tacoma 4x4 ext. or the new double cab...next.
We all still need to setup a meet for the SW. I might be in Louisiana some time next month. I have some work to do at the Convent Refinery, if you are nearby, I'll buy you a few beers Grandpa .

tinygs

I consider myself a rookie when it comes to the REAL tech side of these cars, although I do well on most installs. That was very helpful and informative, thanks Mean Gene. After talking to buddies who are big into car mods, and reading the postes on this site, I think the idea of SLIPPAGE is what is hardest for most people to vizualize. The idea that the TC does not cause the car to simply rev to the stall speed and all-at-once launch like dropping the clutch on a manual. The analogy of slipping the clutch on a manual is the best comparison Ive heard. Thanks again Gene.....Tiny