account2x

iTrader: (5)

Why swap the transmission and the differential when you could just swap the differential? More than a few GS400 owners have swapped in the Supra Turbo auto differential. It is a direct swap, better case casting and most importantly LIMITED SLIP.

A650E/3.77
1st 12.66
2nd 8.22
3rd 5.37

1st gear will be slightly taller - less chance of wheel spin from a stop.
2nd and 3rd gear will be shorter - faster.
You'll be putting power down to both wheels - a HUGE upgrade.

BartleDoo

iTrader: (1)

Well the whole purpose of the manual swap is not to be automatic lol. I understand if you like automatics, but for some drivers it just isn't the way. As for the auto with an auto TT diff being faster, you can't say that with 100% confidence. You can't be so sure it will be faster with a little shorter 2nd and 3rd. I don't think you have seen just how much drive-train loss really exists through these autos.The TT diffs aren't cheap either. They are definitely a prime upgrade for either scenario though. However, whether either is faster by a small margin is not the point. If somebody really wants to be fast with this engine it needs boost which would typically be accompanied by reducing overall gear ratio anyways. Regardless, It's about fun for people who enjoy this. Most people on this site are more worried about numbers and wheel fitment it seems, but there are some of us who live life differently in all aspects. I rock climb, surf, and drive my car hard, all as much as possible. An automatic V8 coupe just doesn't fit into my lifestyle. As long as my car runs 14's and under I can't be too sad about its straight line performance, but we will always crave more.

account2x

iTrader: (5)

Putting power to both wheels (LSD) outweighs any drivetrain loss.

Cheaper than a transmission swap. In other words better bang for your buck.

I'm curious did you buy your vehicle before or after learning about all the performance Lexus SC modifications?

BartleDoo

iTrader: (1)

I bought it after. I didn't even drive it until it was manual lol. The LSD only outweighs the drive-train loss if you're putting out so much torque that you're losing traction in multiple gears which is not the case with a stock 1UZ of any trim (1st gear only but not so much on a sticky track even)...unless of course you're running heller-flush fitment with baby tires or some cheap *** suspension which affords you no traction (which many people are doing both of). That is only straight line of course, but the LSD will make the car much better and more fun on some back roads or a track. So I support either/both mods. It comes down to what a person desires. You can argue numbers to win all day but what are you truly winning? I say it is completely subjective and you say it is a cut/dry answer.

scfou

iTrader: (3)

I think v8's can handle 400rwhp, but that to me is pushing it on stock internals. But I also believe I've heard v8 superchargers producing those numbers without issues. However, my goal is just to hit 400hp at the crank only.

And yes I only want to go manual. I'm sick of auto and even if I were to keep the auto I can easily up the hp while retaining the stock box. The a650e holds about 400whp before you need a valve body upgrade. I'm quite certain that even if I retain the rear end for the a650e, the 5spd swap would still be on top. And when I do eventually swap in a different pumpkin that's more suitable for the w58, it'll be even quicker.

scfou

iTrader: (3)

Forgot to mention also, I currently have the bfi mod done with modified exhaust but I still don't believe that gave me any where near a 30hp increase.

BartleDoo

iTrader: (1)

Those engines respond very well to those two mods. I too have seen the dynos of 270whp with just intake and exhaust.

JustChill

iTrader: (9)

Bringing this back from the dead. Did anyone ever do the 98+ vvti manual swap yet? Did u get the cells fixed?