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sc400 swapping rear end : gears 4.10 vs. LSD

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Old 10-23-10, 05:58 PM
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snowfox444
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Question sc400 swapping rear end : gears 4.10 vs. LSD

I been debating this issue with a few buddies of mine. They are saying I should do change the rear end gears to 4.10 ratio, but I been saying that most of you prefer to do the LSD swap. I want to have more low end power (from a stop taking off full throttle, I would like to be able to burn my tires off without doing a brake stand) They want to lower my 8th mile times and be able to burn out the same way. My friends are more into drifting, spectator drag races... SO what do you guys think abnnd or prefer? I was talking to them about installing a torque converter,but they say that it wont do snap for it unless the car is supercharged or has monster hp gains. They are more partial to the stall converters; saying I will get more gains out of it. I want to race my buddys '01 Bullit mustang 307hp stock and my other friends 3000GT. I wanna get some gains by spring. so I need some advice please? the boys think I dont know what I am talking about because I am a girl.
Old 10-23-10, 06:08 PM
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TLDriver
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the LSD we tend to use are from the auto TT supra... so the 4.10 would get you up and moving faster but your top speed would be lower. With the LSD well you will get off the line slower but faster top speed. Do you know what your current gears are at?
Old 10-23-10, 06:19 PM
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lev00221
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Hello snowfox444,
Good to see a lady that takes a genuine interest in her car. What year is your SC400?
If you have a 92-97 you likely have a 3.92 rear end and thus the difference between that and a 4.10 won't be that substantial off the line. What it will do is raise the RPM's when cruising on the highway. Depending on how loud your exhaust is this may or may not bother you. The LSD won't really help you accelerate faster but it will make the car feel better (more stable) when accelerating and in general. You can swap the LSD into your existing rear pumpkin fairly easily. If you purchase a Supra TT LSD it will come with a 3.77 rear end which would actually make you slower off the line (not what you want).

Check this thread out post #3:
https://www.clublexus.com/forums/per...eed-trans.html
Old 10-25-10, 03:46 PM
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snowfox444
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yeah I was reading on the rear end gears mine is a 95 sc400 so the 3.92 is correct. In a perfect world i would love to have HP gains, good top speed adn faster quarter mile times with plenty of torque from the starting line. But I highly doubt all that will be affected by swapping out rear end gears or with the tt supra lsd rear end. They think swapping out the rear end gears with 4.10 would only cost about 80$ where I found the lsd from the supra to be around 900$. Also, online I couldn't find nothing for gears for this car. lol But I have made my friend jealous with the minimal mods I have done to my car where his Bullitt Mustang is completely OEM. But I would like to race him again and beat him this time. We did a quarter mile race in the back roads some months ago my automatic had managed to keep up with him until he reached 3rd gear then he took me. yeah thats what happens when you grow up with close uncles who rebuilt muscle cars like 60's chevelles and chargers and a younger brother who races bikes. I tend to hang with the boys rather than the girls. Id rather have fun playing with big boy toys than playing drama queen lol.

as for the link provided, that 4.27 or 4.30 seems way more like my taste

Last edited by snowfox444; 10-25-10 at 04:01 PM.
Old 10-25-10, 05:26 PM
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Swapping rearend gears will not cost 80$ unless you do it your self and some one sells you the ring and pinion on the cheap. A LSD will run you around $1000 for a TRD one in parts. 4.1 will run $150 for the ring and pinion. now you will need to drain the diff fluid, drop it, change the gears and make sure it is shimmed the correct way. swappung to the 4.3 would be worth it. It will give you the seat of the pants feel to the car. but IMO if you dont have the basic mods first like intake and exhaust, Id start there. Converter wont get you anywere. Id get an intake and exhaust THEN 4.3 rear gears. A Lsd will only give you better traction and will do nothing if you race from a roll. Itll help for about the first 10 feet racing from a dig (stop)

Also you dont have to choose between a LSD and Gears. You can have both!
Old 10-25-10, 07:16 PM
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RED95sc
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you could probably just put a sc300 diff in, that seems to be the cheapest way unless you really want LSD. just be warned, this will take a negative effect on your gas mileage. at 80mph, im cruising at 3k rpm, with ur 400 diff, ur prolly at 2.5krpm. but if you wanna the stang, why not just do engine modifications instead of messing with the diff.
Old 10-25-10, 07:25 PM
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1JZPWRD
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Do a BFI mod, delete the cats and resonators and then try to rerace him. These are simply mods that have been noticeable better throttle response and a tad bit of torque. You may also want to play with your TPS or unplugging your MAF sensor. It will be a trial and error, but these are simply to do. JMO. Good luck with whatever you choose.
Old 10-25-10, 07:39 PM
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Originally Posted by 1992Lexus
Do a BFI mod, delete the cats and resonators and then try to rerace him. These are simply mods that have been noticeable better throttle response and a tad bit of torque. You may also want to play with your TPS or unplugging your MAF sensor. It will be a trial and error, but these are simply to do. JMO. Good luck with whatever you choose.
I'll have too look that last one up, that dosent make sense.
Old 10-25-10, 08:26 PM
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RED95sc
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if you unplug your MAF sensor, you will accelerate nowhere
Old 10-25-10, 09:06 PM
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Originally Posted by RED95sc
if you unplug your MAF sensor, you will accelerate nowhere
this is apparently not the case in 92-94s. I have not tried it yet myself, but some have...

https://www.clublexus.com/forums/per...n-92-94-a.html

EDIT* and I see she has a 95...
Old 10-25-10, 10:31 PM
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Originally Posted by keskipper
this is apparently not the case in 92-94s. I have not tried it yet myself, but some have...

https://www.clublexus.com/forums/per...n-92-94-a.html

EDIT* and I see she has a 95...
hmmm, news to me, i thought all MAF worked the same way, it reads the air coming in so the ecu can make adjustments. however, why would it work on 92-94, but not 95 when the 95 is obd1
Old 10-26-10, 06:28 AM
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I have a welded 4.27 rear end. Its fun
Old 10-29-10, 05:40 PM
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snowfox444
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Originally Posted by TheRonTom3
I have a welded 4.27 rear end. Its fun
did that make it posy? I am thinking 4.55
Old 10-29-10, 07:38 PM
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I think it funny when people say posi. It's like hemi. Any ways welded diffs are awsome. 4.27 is that from a sc? Aristo?
Old 10-29-10, 08:13 PM
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You will need a heck lot more than LSD/Gearing to keep up with that Mustang.

Mind you going with shorter gearing will gain you low end but you can fall off at the top end really quick. You're not always going to be quicker with the 4.10 vs the 3.92


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