'92sc400

Ok, i was wondering if anyone on here has put a high stall converter into a stock sc400? and i wanted to know, if you guys in fact did put a higher stall converter in, what stall speed? I was thinkin about gettin a 3000 stall converter myself. I race the car so i want a higher stall but i wanted to see what you guys recommend. Do you guys think that would be enough to get me into the 14's at the track? or at least low 15's? right now, the cars best run was a 15.7. That was at a track that goes uphill 8 ft. though and it was a humid day.

any help's appreciated

thanks a lot,
jason

eddie187

i haven't put one in yet. there has been a few people on this site has put one in. if you use search you will find some information. most people use a 2800 stall I'm sure you can have a higher stall then that. for performance gain is about half a second faster in your 0-60mph times from a 2800 stall. you should look into a tranny cooler because your tranny will be working harder. one thing more you will lose top end speed from the information i got. i hope that helps.

Teflon Don

As previously mentioned, you really need an additional tranny cooler fitted. We have a place over here that actually modified the stock TC to high stall specs. On the 2.5 soarer it makes all the difference on a single conversion.

MJHSC400

Another tranny mod is as simple as tightening the pressure actuator-- It connects to the tb just under the TRAC cover-- I tightened mine all the way save 1/4" -- so I moved the adj about 3/8" -- My tranny was WAAAYY too smooth after test driving 350z's and Maximas for a year--

The actuator just tells the tranny where the throttle is for load and gear selection-- this will increase your line pressure (shift kit anyone?) and hold gears a little bit longer--

Exactly what I wanted --

Higher stall is the next mod on the list along with exhaust and intake-- poor man's budget--

http://www.dynamicmanufacturinginc.c...lrequests.html
Torque Converter Rebuild-- $200 or so--

'92sc400

wait, how will it hurt your top end performance? wouldnt it just be the same on top end but just a crap load faster on bottom end?

i'm not too worried about top end anyway though. i race at the drag strip and bottom end is everything there. I hate to say it, but those sc400's cant launch to save their lives. They're just not good at launching. They have an amazing top end though. my best 60' was 2.41 and my worst was like 2.63. even the 2.4 is pathetic.

Can i just send my current torque converter out and get it rebuilt rather than buying a new one for 750 bucks? If i got it rebuilt, would it cost a lot less than buying a brand new one? i dont plan on putting a stock converter back into that car anyway.

mkorsu

Well, it definately won't be a "crapload" faster, but it will quicken it up a bit. The 1/2 0-60 estimate quoted before is quite a bit optimistic! Maybe 2/10 of a second is more realistic. That could in turn equate to 3-4 tenths in the 1/4 mile. 15.7 down to 15.3 is very respectable for a single mod like this.


You won't lose any top-end. All the torque converter is doing is moving the rpm that the trans sees full load at up to a higher rpm. Effectively putting the engine more in its power band. It has NO effect on gearing. Perhaps the other person was confusing a higher ratio rear gear-set with the torque converter.

Now...on to your 60' time. Dont expect any huge gain here. The car just doesn't have the power. Even a converter set with a stall speed of 3000-3200 rpm's will not get you into the coveted sub 2 sec 60' times. From 2.4 to maybe 2.25-2.3. Get the car up over 300 hp and you'll start to see better dividends from that converter.

Blizzy

iTrader: (-1)

The increase in the stall speed will definitely get you off the line quicker.

One thing to consider: a rebuilt torque converter could end up being heavier than the stock unit from the build up. This would mean a decrease in throttle response. This is a consideration. The PI Dragon Torque Converter is not only lighter but also a couple inches smaller in diameter, which means an increase in throttle response in addition to the added kick off the line.

A high stall means nothing if you can't put the power to the road. No sense having a set up where you would roast your tires if you applied any aggressive accelerator pressure from a dig, right? This means an LSD is required to get the most out of your torque converter.

I agree with the man above: he knows his stuff. 0.3s is probably more like it. 260hp can only look so good on a drag strip.

RedPhoenix

iTrader: (10)

what do you think of the lextreme TC?

ScottURnot

iTrader: (33)

I'm with Blizzy and mkorsu on this one.
I have a PI Dragon, I cant say what it did on its own becuase I did several other mods at the same time but is does improve off the line performance. I did the LSD at the same time and it was like a new car. The true secret, More HP, I guess its no secret.

Will the stall converter Improve your cars performance? Yes
Will it limit your top end? No
Is this a good Mod?
"Another tranny mod is as simple as tightening the pressure actuator-- It connects to the tb just under the TRAC cover-- I tightened mine all the way save 1/4" -- so I moved the adj about 3/8" -- My tranny was WAAAYY too smooth after test driving 350z's and Maximas for a year--

The actuator just tells the tranny where the throttle is for load and gear selection-- this will increase your line pressure (shift kit anyone?) and hold gears a little bit longer--"
Makes me nervous!
Which Stall is best? PI Dragon, but if on a budget, do the stock modified.

Hope this helps.
All else fails, [B]supercharge it!/B]

'92sc400

ok, well every tenth in your 60' is equal to pretty close to 2 tenths in the quarter.(i've been racing since i was 13) i was hoping to see right around 2 sec. 60' with a 3000 stall converter. What is the stock stall speed? and what is the LSD you guys are talkin about? maybe a dumb question, but i'm bad at figuring out abbreviations. haha.

and one more thing. what are the rear-axle gears in the sc400's. I looked online but couldnt find anything through a google search. so, i found one link that had the final drive ratio and figured the rear gearing out on my own from there. The number i came up with was something like 4.829xxx. does that sound about right? that sounded extremely high to me. but i forgot, foreign cars are geared a lot higher than american because they dont make any kind of good low-end torque. like 4.10s would be perfect for my 65 buick. but that thing has 445(gross) foot lbs. / tq.

is the 250 hp and 260 tq. rating on these lexus's rated in gross or net? i'm hoping net. otherwise, if gross, then the net is actually like what, 190hp or so?

thanks for the help guys!

ScottURnot

iTrader: (33)

LSD Limited slip Differential Most of us install the Supra TT auto


Here are all the gear ratios for the SC and Supras.


92-97 SC300
6 cyl, AT (4.27 ratio)
6 cyl, MT (4.08 ratio)

98-00 SC300
6 cyl, AT (4.27 ratio)

92-97 SC400
8 cyl (3.92 ratio)

98-00 SC400
8 cyl (3.266 ratio)

92-96 MKIV Supra

w/o turbo; (4.27 ratio) Limited Slip
w/o turbo; (4.27 ratio)
w/turbo, MT (3.133 ratio) Limited Slip
w/turbo, AT (3.769 ratio) Limited Slip

97-98 MKIV Supra
w/o turbo; (4.08 ratio) Limited Slip
w/o turbo; (4.08 ratio)
w/turbo, MT (3.133 ratio) Limited Slip
w/turbo, AT (3.769 ratio)
w/turbo, AT (3.769 ratio) Limited Slip

'92sc400

oh ok. 3.92. the site i got the final drive ratio must have been wrong then. i know my formula for finding the rear gears was right because i've used it before on rear-ends that i already knew the gear ratio on before hand. to test and make sure it was right. the site that i got that info off of looked kinda crappy anyway.

thanks.

Blizzy

iTrader: (-1)

If you really want a drag car, source a differential from an SC300 AT (4.27) and drop a TRD LSD into it. You will roll through your gears quicker, and you should notice the extra whip off the line. This in conjunction with your 3000 stall converter could get you pushing your 14's.

ps. don't forget the tranny cooler to maintain reliability

'92sc400

yeah. so, now, on my parts list, i've got: 3000 stall converter, tranny cooler, and sc300 AT rear end.

That shouldnt be that hard to find. There is this junk yard where i am located called Harry's U Pull It. It has like everything you can imagine there. I'm sure there are over a thousand cars in that lot. So, when i go up i can check for sc300s. And if i get lucky and find a rear end on dollar day i can get the whole thing for a dollar. Maybe i should try to find a wrecked supra too and snag the engine on dollar day. ;-)

You guys have been a really great help. anything else you can think of, then just let me know.

MJHSC400

Increasing line pressure by tightening the actuator will only REDUCE trans heat-- It speeds gear changes and greatly reduces the smooth out flare-- greatly-- You have to remember that these Lex transmissions are programmed to slip the clutches in and out of gears during shifts to make them undectable-- This slippage GREATLY increases heat and wear-- Speeding up the shifts will do nothing but make your car faster, sportier, and make the trans last longer--

I'm so glad I did it--

Higher stall is very normal even in cars with MORE power, like a Maxima for example-- The new Maxima's and 350z's have a much higher stall than these SC's have--

I also think the GS has a lower rear end ratio indicating that lex was trying to make a heavy car faster -- just happens to be about the same weight of an SC4--

I would of course rather just install an R154 and be done with all this slushbox business-- I hate automatics--

I'm seriously leaning toward going IS300 -- or 540i --