JIBBBY Posted May 1, 2007 Posted May 1, 2007 I know you guys with the SC400's are just frusterated with the slow take offs... You hit the gas from a dead stop and the car takes forever to get going... Your probably thinking, hmmm why is a V8 motor so slow from a dead stop?.... Example: Ever been in the far right lane at a stop light and need the power to pass when the light turns green? I bet you have been there and backed off fully knowing the SC400's just aren't spunky enough out of the gates... So what do you do? You wait in displeasure for an opening rather then hit the gas and pass... That to me this is the worst aspect of these SC400's... It's a disgrace considering the car is a sports coupe...Right or wrong? Well, the reason for this is not because the car doesn't have enough engine power, but it is because of the design of the stock torque converter...The torque converter transfers the power from the motor to the transmission and wheels... It basically slips the engine power to engage the automatic transmission... The Lexus designers made the cars this way for elderly drivers in my opinion, so they won't spill coffee, get a neck jerk or have a heart attack at launch.... The SC400's actually possess the power to actually do a burnout at launch if you can believe that....You need to change out the stock torque converter to a 2200 stall rate torque converter..... I have had mine changed out for over four years and still think it is the best upgrade I ever did for the car... I installed a Precision Industries "dragon torque converter" and got those rears spinning from a dead stop immediately... This only applies to the automatic transmissions found in the SC300 and 400's.... I just thought I would share this bit of information with you guys, because with a torque converter upgrade it really changes the car around totally...Like driving a Camaro V8 or a Ford Mustang GT from a start rather then an SC400... The Dragon Torque converters are a bit pricy, so an alternative at Lextreme.com or maybe a local transmission shop may be your most cost effective choice... The great thing about it is that the driveability remains the same, it just really improves throttle response at launch... Something to think about if your tired of getting used off the line..... Oh, and any tranny shop should be able to install a torque converter for no more $350...
schott1984 Posted May 1, 2007 Posted May 1, 2007 I like this idea... I got burned by my friend's GTP this weekend. Mostly because of his speed off the line. It's embarrassing. I'm definitely considering this.
JIBBBY Posted May 1, 2007 Author Posted May 1, 2007 That was exactly my thoughts too... About 4 years ago when my SC4 was completely stock I just got so frusterated, I would race a Pinto and get used off the line for the first 50ft..... From a stop I would be nervous to race a big rig, or a bus...(just kidding of course) The takeoffs were pathetic and embarrassing and that is why I posted this thread... Also, I had previously owned a Camaro, Trans Am, Iroc before so I knew the takeoffs should be better with a 32 valve V8 motor... That is when I changed out the torque converter... Instant gratification.. 0-30mph was night and day..I was immediately able to hang with Mustangs, Camaro's, etc.. 1rst and 2nd gear became very fast in my SC400 with just the torque converter change.... I would floor the pedal from a dead stop and the rears would break loose... If I then eased into the throttle it drove just like stock... No head jerks, and I could still take grandma out for a drive... You guys really don't know what your missing... However, the downside once the torque converter change was made teased me and that is when I got hooked on making my car even faster on the topend...Becareful horsepower is addictive....
schott1984 Posted May 1, 2007 Posted May 1, 2007 Your sig says built tranny... Is that just the TC upgrade? What else is done tranny-wise?
JIBBBY Posted May 1, 2007 Author Posted May 1, 2007 No the tranny build is the upgraded parts switched to create a stronger transmission...Has nothing to do with the torque converter change... I was running a 150 horsepower nitrious shot and that combined with all my other mods actually killed my transmission in second gear... Gave up the ghost due to pushing to much horsepower... The torque converter does not create more horsepower, it just transfers the torque better from the engine to the transmission.... A torque converter change will not harm an Sc400 in anyway...
SuperCoupe400 Posted May 2, 2007 Posted May 2, 2007 Hey Jibby, will the Trac Control still functon properly with the new torque converter?
JIBBBY Posted May 2, 2007 Author Posted May 2, 2007 Traction control is completely seperate and has nothing to do with the torque converter... There will be NO ILL EFFECTS what so ever when upgrading the torque converter.... No worries about anything other then the price of the torque converter and installation costs... The cheapest way to upgrade your torque converter is too purchase a used one at the junk yards or on Ebay or something for maybe $100...Send it in to Lextreme or some torque converter shop and have it recalibrated for around $400...Then install it at a local tranny shop for around $300...That is what I would do... The expensive way is to pay $900 for a Precision Industries "Dragon Torque Converter" then another $300 for installation...Then maybe sell your stock one for $100 bucks on Ebay...That is what I did.... It is not a cheap mod by any means but it is oh so effective... It will bring a smile to your face guaranteed..
tooslow710 Posted May 2, 2007 Posted May 2, 2007 hey im just wonderin looking at buying a sc 3 or 4 want to mod it. would any of you sc4 guys have gone back on your decision or was it worth while to get the 400
coolbum_sc400 Posted May 2, 2007 Posted May 2, 2007 hey im just wonderin looking at buying a sc 3 or 4 want to mod it.would any of you sc4 guys have gone back on your decision or was it worth while to get the 400 iv only had my 400 for a little over week now but im so happy with it. my plans our to hook it up thats all i do anymore is look for parts and price's. i have not once wished that i had gone with the 300 though.
JIBBBY Posted May 2, 2007 Author Posted May 2, 2007 Alot of Lexus performance junkies like myself prefer an SC300 because of the manual transmissions option...The SC400 automatic transmissions are limited. THe SC300 are a bit easier to modify too.... I prefer my SC400... Plus I like the trunk wing...
SuperCoupe400 Posted May 2, 2007 Posted May 2, 2007 I prefer my SC400... Plus I like the trunk wing... OHHHHHHHH YEAHHHHH! :D (as the Macho Man Randy Savage would say) Gotta have the (1st gen) wing. The car is simply naked without it. Had I gone with the 300, I'd have bought a wing for it before even taking delivery of the car itself.
cody4488 Posted May 3, 2007 Posted May 3, 2007 In and of itself, will this have any effect on gas milage?
JIBBBY Posted May 3, 2007 Author Posted May 3, 2007 Probably you will get slightly better gas mileage, because there will be less slipage and more engine to tranny lockup with a better stall rate torque converter... The engine will have to rev less to engage the wheels which should make for better gas mileage...
sc300tt Posted May 8, 2007 Posted May 8, 2007 so you upgraded to a stall of 2200? isnt that what auto TT supra are stock? im actually thinking of going to 3200 on my car. PI qouted $735 plus shipping, i doubt shipping could be another 150 bucks. not bashing :chairshot: your thread i think its a great idea to get one. i found a used 3800 but not sure if i want to go that high.
TeamTorq Posted May 10, 2007 Posted May 10, 2007 Is there any difference if I sent one in to a company to be re done rather than buying the dragon TC? Is one better than the other or is it just price difference?
JIBBBY Posted May 10, 2007 Author Posted May 10, 2007 Is there any difference if I sent one in to a company to be re done rather than buying the dragon TC? Is one better than the other or is it just price difference? No difference....The difference is in the stall rate set inside the torque converter... You can either have your stock torque converter re-calibrated to a newly desired stall rate or you can purchase a new one that is preset like the Dragon....It really doesn't matter...
pingpong Posted May 11, 2007 Posted May 11, 2007 hmm i never had a problem taking off =] mine would spin tires easily heh. my car (92 sc400) left a LONG tire treat marks at my school's parking lot hehe =] i raced a mercedes c230 (i think thats it.. supercharged) off the line it was like 3-4 feet ahead of me.. after a second or so i smoked it.
eddie187 Posted May 11, 2007 Posted May 11, 2007 the stock stall speed is 2100 on the sc400 most people i see is getting 2800.i raced a mercedes c230 the other day i had a jump on him never look back. i thing the performace of this car is not bad for 93.
schott1984 Posted May 11, 2007 Posted May 11, 2007 bah. I disagree. Mine's slow as fvck off the line. Got smoked by my friend's GTP, and that *BLEEP*ed me off haha. Considering the numbers between the two cars are so close, I was mad about this.
JIBBBY Posted May 11, 2007 Author Posted May 11, 2007 They are all painfully slow at stock... I use to deal these cars 92-96's and they were all slugs off the line unless you brake torque...Even brake torqueing they were still slow... Pingpong if your SC4 spins off the line then you do not have the stock torque converter in your SC.. I also highly dought a stock 93 SC4 can beat out a new Merc 280....
SuperCoupe400 Posted May 11, 2007 Posted May 11, 2007 Pingpong if your SC4 spins off the line then you do not have the stock torque converter in your SC... Question is - how much spin (off the line) constitutes a 'spin'? Because my '93 SC4 rutinely yanks a good 1 to 1 1/2 seconds of dry pavement with the traction control shut off - which I'm certain is not the result of a moded TC. if the TC were moded, the wheels would spin practically all the way through first (or at least I would imagine).
schott1984 Posted May 11, 2007 Posted May 11, 2007 Yeah, I can get a good squerk in here and there with mine. It seems more prevalent if I shove the pedal quickly to about 3/4 throttle instead of full throttle. What's the proper brake torquing method btw?
JIBBBY Posted May 11, 2007 Author Posted May 11, 2007 Yeah, I can get a good squerk in here and there with mine. It seems more prevalent if I shove the pedal quickly to about 3/4 throttle instead of full throttle. What's the proper brake torquing method btw? Brake torqueing - Press the brake down hard, then you rev the motor up while still in place and then suddenly release the brake and then off you go..... Not recommended.... First off - If you get a spinout in your stock SC your tires are bald and the road is wet, and it is only one rear wheel spinning and not both... No seriously, first off you are only getting power to one rear wheel via the open end stock differential, the stock tires are skinny, maybe the ground or your tires are slick. That is the only way I can see an SC400 breaking loose out of the gates... From a dead stop, when you floor the SC4's they simply do not jump out of the gates... That is fact... I would be very suprised if I ever saw a stock SC do a wheel spin from a dead stop "both wheels"...Not going to happen, sorry fellas... With my torque converter and Supra Limited slip different (traction to both rear wheels) and my fat rear tires from launch, both rears skreetch out of the gates, the front end lifts a bit and I get thrust back into the seat...No nitrous either... That is what the Dragon Torque Converter did for me.. With the 100whp Nitrous system activated and from a dead stop I can peal out for half a block, and that is thru both 1rst and 2nd gears then in third I cherp and finally grip.... That is major wheel spin not to brag... With that being said I never hit the NOS in first gear because the torque converter is sufficient enough to take care of my 1rst gear speed and take offs...
eddie187 Posted May 13, 2007 Posted May 13, 2007 They are all painfully slow at stock... I use to deal these cars 92-96's and they were all slugs off the line unless you brake torque...Even brake torqueing they were still slow...Pingpong if your SC4 spins off the line then you do not have the stock torque converter in your SC.. I also highly dought a stock 93 SC4 can beat out a new Merc 280.... i sure did bet a new merc 230 there not that fast and a few other cars. i know this car is not the fastest on today's road but surely its not the slowest
option00002 Posted May 13, 2007 Posted May 13, 2007 If you think a stock SC4 is quick off the line then you obviously have had little experience with truly fast cars. They are all dogs off the line without the conversion and will not lay rubber no matter how you decide to beat on it. Sure a chirp, but not anything like it could be. my .02
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now