Brendon

iTrader: (1)

Lately I've thought about turning my Lexus into a true SC400. I need some advise first (particularly from Scotturnot, since he supercharged his 97' as well). I'm looking to have an easy setup that requires minimal fabrication and modification, sort of like the bolt-on superchargers TRD sells for cars like the Corolla and Scion tC. I'm not looking to run a high boost. I would probably run only 5-6 psi. At 5 psi, my calculations estimate I'd be making about 340-350 HP (from 260) at the flywheel. At 6 psi, I'd be around 360-370 HP at the flywheel. That's more than enough power for me to give my daily driver some extra muscle. Here's my questions:

1) How much power/boost can the stock engine internals handle? A guy on youtube called kc95sc400 claims that "96 and up SC's have weaker rods" which makes them more difficult to supercharge.

2) How much can the stock 4-spd auto tranny handle?

3) At what point is an intercooler required, or is it neccessary for any boost level?

O. L. T.

iTrader: (17)

twizted

iTrader: (2)

1) How much power/boost can the stock engine internals handle? A guy on youtube called kc95sc400 claims that "96 and up SC's have weaker rods" which makes them more difficult to supercharge.

Stock can take 6psi with the aid of a riseing rate FPR after that you need acu upgrades and after 9-10psi you need to lower the compression and more fuel.

2) How much can the stock 4-spd auto tranny handle?

I dont know of anyone that has blown one up yet, ill let you know im going for 10-12 then later 15-18 psi so i will be blowing it at some point

3) At what point is an intercooler required, or is it neccessary for any boost level?

IMO its not needed if your pulling cool air a roots style atleast runs pretty cool. I Dont know how much sucking through a intercooler with a s/c would help. Water meth injection will help though

I am selling a m90 kit soon because i have a m112 im moving up to. I have a buyer but if he doesnt want ill let you know. You need to be mechanically inclined because no matter what you do you have to fabricate some parts. Extend throttle cables and be able to mess with the fuel system

Blizzy

iTrader: (-1)

The 96+ SC's do have smaller rods, but they are holding up in a number of supercharged GS400s that are running nearly 400 to the wheels. Anything north of 400, and you are playing with FIRE. But, for the levels you are proposing, even the OBD-II bottom end will hold up.

KC95SC400 is a forum member here. I am as familer with his car as anyone elses on the forum. He is running ~400hp/tq at the crank through the stock auto (with a PI Dragon stall converter) and the stock bottom end from the 9lbs of boost he is running through a Vortech V9 Centrifugal blower.

If you are looking to run ~300whp, an intercooler will not be necessary, although it is always added insurance. That being said, on a low boost application, boost response might be an issue, and non-intercooled is always the way to go in that regard since it keeps the intake plumbing most compact.

KC is running and I will be running a centrifugal supercharger (a belt driven snail - looks like a turbo). The centrifugal blowers are more efficient but take engine revolutions to build boost. When only running 4-5psi, you would be running a large pulley on the blower that would not build boost until late in the rev range.

Scott is running a positive displacement blower (mounts to the intake manifold directly - looks like the engine has a tumor). The PD blower are less efficient in most cases, but they build boost from idle to the redline. Throttle linearity feels like stock, you are just making gobs of torque that you didn't used to.

DasBach

iTrader: (7)

Its threads like these that make me want to trade in my SC300 for a 400 haha.

Brendon

iTrader: (1)

So would that mean the S/C wouldn't kick in until WOT? How late in the rev range would it be before the s/c kicks in? 3000+ RPM? What about if I ran a bit higher like 6 psi?

Yeah, quite honestly I bought the SC400 instead of a 300 just because the V8 sounded cooler (also because it was the first one that I found both 97+ and red). Unfortunately neither the SC400 nor the SC300 were really that fast. I don't need a car that's rediculously fast, just enough to compete with the new sports cars out today like the G37 or the 335. A 0-60 of high 4s to low 5s is enough for me.

There's a little competition me and my friend have about who has the faster car. A year ago, when I had the 98' Corolla, his car (manual 4 cyl 00' Eclipse) was much faster. Now that I got the SC400, I'm ahead, but he just graduated college and finally got a job. He's shopping around for a new car which is probably going to be faster than mine. I certainly don't want to sell my SC400; its the car I've wanted ever since I was a kid, but it's a bit embarassing that my 8 cyl engine makes signifantly less HP than most 6 cyls today and that its slower than some 4 bangers like the Civic Si.

twizted

iTrader: (2)

Its because of it being a heavy luxury car, it was never really suppose to be a sports car i dont think. You can upgrade it, most people love the body style then modify it from there. I love it because of how it looks so i wasnt worried about how fast it was to buy but was always going to modify. Why would you sell your own car just because you buddy might get a faster one anyway? Thats kind of dumb, dont worry about what you friends are driving, do what you like...

over40driv

As long as you have lots of time and money, along with extensive mechanical ability...... youre in.

Brendon

iTrader: (1)

When I talk about making my car faster to my friends at work they tell me "if you want a faster car, just buy one". It annoys me; there isn't a single car I would want more than my SC400. I think its the most beautifully designed car; it deserves to be much faster (I think it looks fast). Yeah 3600 lbs is heavy, but not really compared to the other high performance sports cars out there today:

Infiniti G37 = 3616-3668 lbs
BMW 335i coupe = 3759-3770 lbs
Audi S4/RS4 = 3869-3957 lbs
Audi S5 = 3593 lbs
Lexus IS-F = 3780 lbs

twizted

iTrader: (2)

If your going to do it just run the roots. You will pleased, I make good boost through out the torque range you get really good boost and start to feel the pull at about 2000rpm. I can sit and brake torque it and it shoots out of the hole like you wouldnt believe with only 6psi. The first time i drove it i was like damn this is how it should have been from factory!

over40driv

Twisted, im guessing you have an aftermarket torque converter and LSD to go with your blower.

twizted

iTrader: (2)

Nope not yet, thats the next one my list. Im able to keep traction with a bit of chirp do to my 275/30/20's i believe...

Blizzy

iTrader: (-1)

The centrifugal blower needs rpms to make boost. It looks just like a turbo (and acts similarly). You should see some boost at 3000rpm if you are running a pulley to make 6-9psi.

KC is running a V9 blower at ~9psi. He sees boost almost immediately off the line with a little brake boosting to launch. The V9 is the smallest of Vortech's blowers, so it makes it boost rather quickly.

A larger blower like a V2 or a Novi2000 would be 5-800rpm behind in boost production, but the power numbers would be significantly higher. That being said, a V2 or Novi2000 could outblow the bottom end very easily.

In my opinion, the set up KC is running at the moment should be in your consideration with an M90 (Roots, Positive Displacement) set up.

I have personally helped KC to crop some of his videos to record 0-60 times from the speedometer. He can run 4.6s when he hooks up, which is pretty damn fast for the set up that only ran him ~$4k.

I am going to be running a Powerdyne blower, which is damn near impossible to find in reverse rotation, a bit more powerful than the V9, but quite a bit more tempermental as well. Ultimately, I would love to run times similar to KC. He has set the standard for we centrifugal SC400 guys (he is the only one at the moment...I should be #2 in a month or so).

--------------------

If I were you, I would consider the M90 kits that are available from Australia. Richwood and Rush both make nice kits that include quite a lot of what you would need. An M90 would make more torque and less power, giving you a "big block" powerband. I know of one guy in Australia running 12psi on a positive displacement blower making 350whp and 650wtq!! His car has to be one kick in the pants to drive.

I would also consider using the Fish bracket from Lextreme to utilize a centrifugal blower. This route will likely entail more research, but I think you can save more money and make more power, more easily...albeit with much less torque than a positive displacement blower like an M90. That being said, KC builds boost almost instantaneously when he launches, and has a very fast car that is within the reasonable limits of the bottom end and the transmission both. His car is daily driven, so he has had the longevity of the car in the back of his mind the entire time.

As a final vote of confidence for the 1UZ, KC has well over 100k miles on his motor and it is going strong. Neil, the guy making 650wtq with a positive displacement blower, has over 200k miles on his motor and it is completely unaltered. A simple set up to run 5.0s in a 0-60 run will not blow up the motor.

Either way, you will get your goal. Research the centrifugal and positive displacement blowers to get a feel. I would also not hesitate to PM "Scotturnot" and "KC95SC400". For that matter, don't hesitate to PM me. I have a home-made supercharger kit sitting in my garage right now waiting for the five speed to be up and running before it gets installed.

Regardless, I really love your enthusiasm for the SC400. It is a great car, and the modifying the V8 is definitely the way to make a very special car that sounds good enough to make the American V8 owners jealous and goes fast enough to leave 99% of cars in the dust.

Punky

iTrader: (4)

You're comparing the SC400 to brand new cars. If you compare it to cars in the years of production as it was you'd notice it was a fairly quick car running with CLK430s, M3s, GTs and so on. Newer car, new technology to make it go faster. Build what you have since youre happy with it. I bet once you get some BPU upgrades in there it will make you love it more every time you go WOT let alone once you Supercharge it

morris

iTrader: (2)

As someone that ran a centrifugal blower on a stock 1uz from 7-12 psi, I am going to have to throw the Bovine Scat flag on this.

At least in my experience and the others I know that ran a similar setup on their 1uz's the car will pull like a freight train from idle all the way on up. In fact I was able to smoke the tires from a standstill with no problme, in fact I had to learn how to meter the throttle to prevent this from occuring, particularly when powering our of a corner even at lower rpms