I dont have a sc400 yet but im going to look at a 93 with a 130,000ish miles. I love the aesthetics of the car and ive read good things as far as reliability and stuff goes. My concern is that I can't seem to find much for aftermarket upgrades. I plan on just enjoying the car as is for awhile but eventually it would be nice to have the option to up its performance to the 300-400 hp range. Is this even realistic based off of performance part availability/cost? Ive read the stock internals can handle it. Any insight is greatly appreciated.

 

^^ Everything Sargon just said.

That 1UZ-FE engine is one of the most over-engineered and ultra-reliable (with reasonable regular maintenance and normal oil changes) V8 engines ever made. However that does not mean it is the most powerful or most tune-friendly V8's ever made.

The easiest way to have more fun with it would be to leave the V8 alone at its current level of power and do a W58 manual transmission swap, add an LSD, upgrade the front brakes, suspension, etc.

For a lot more money and custom work you could look into importing an Eaton M-series roots supercharger custom intake manifold, do a custom fuel system with an aftermarket ECU and full tune, etc., etc. Add even more money to the budget if you want to build totally custom for twin turbochargers.

...

Beyond that you can make that SC400 into a 300-400hp car (or much more) within a somewhat reasonable and predictable budget by removing the V8 and installing a 2JZ-GTE, 2JZ-GE set up for NA-T or a 1JZ-GTE. And with that you'd need to install the beefier A340E (30-40LE) with a "J" in the bellhousing casting 4-speed auto or one of several strong manual transmission choices.

Contrary to what most people think, it is the V8 SC that is the "economy" engine (though it's a very strong and respectably powerful one at that) and the I6 SC that has the much more performance oriented engine. Thankfully swapping and wiring is so well covered and parts support is so strong that this makes for a very easy option to make much more power if the stock 250hp is not enough even with a manual swap.

Another option, although far less traveled and with far less support on the aftermarket, is the tried and true LSx V8 swap. This is still getting into a lot of custom work but the basic mounting kits and some things used to adapt them to SC's are out there in the aftermarket.

At the end of the day though the easiest and most straightforward route to giving your SC400 far more horsepower is to swap in and install a turbocharged 2JZ or 1JZ engine. Like the 1UZ-FE the chassis and all surrounding hardware were engineered for it and all you need to do is assemble the right combination of parts to have a factory high performance engine and chassis combination that just fits and works because the platform was designed to accept it.

The other alternative of W58 manual swapping the stock 1UZ-FE will not give you any more horsepower than stock (and no, the bolt-ons won't add very much) but it will free up some power soaked up by the factory automatic transmission. The W58 is more than capable of handling the 256hp/260ft-lbs for years. Swap kits for this are available on the aftermarket.

 

A low-mileage '93 sounds nice, but if you think you're going to want a bit more power, a '98-00 SC400 will put you right at the doorstep of that 300-400 HP goal.

 

My older son was going the route of the eaton supercharger for his track '93 SC 400. His plan was to cut the hood to fit the supercharger. He had bought a KA24 five-speed from a guy who had wrecked 240SX. We still plan to put this in when I get time.

I have the '99, which has more HP with the five speed auto. I'm fine keeping that stock.

 

I doubt that tranny will last long behind a supercharged 1UZ.

 

We will see. When he was doing the work, he had told me that the KA24 was rated for up to 800HP. Also, he was using a '93 1UZ, which has the stronger internals than used on my '99.

 

You should know better than to trust family. Most people say either 300-400 HP or 500 HP max, but even the latter say 450 ft-lbs off the line is too much shock for it. The 1UZ is a torque mini-monster... Supercharged, you'll probably end up around the limit of the higher of the two estimates.

 

Well, we'll see what happens. At the moment, that SC is sitting at a friend's shop. Funny, I haven't looked at it in a few months. Those wheels are awful.

 

Man you guys bring up alot of good points...I have my eyes on an apparently abandoned sc300 maybe 400 haven't approached it yet... would love to jump off the cliff with it, since mine looks too nice to Mickey mouse...

 

The ka24 will be fine behind a stock 1uz, but not a supercharged one... would just be a waste of time, money and a transmission someone can use on something with lower torque.
Maybe if you do a turbo instead and keep the boost on the lower side it may survive cause the torque won't come on so fast (you know like a KA or SR which they are normally behind, forget HP and think torque).
I would turbo an early 1uz, getting a proper supercharger setup on that engine will cost more and make less power. If you have to have a supercharger then go for it but at least step up to an R series transmission.
If you don't want to splurge for an AR5 or R154 you can get a used 2wd R150 out of a tacoma for practically nothing and with an adapter or aftermarket bellhousing that would last better behind the v8, just needs a shifter extension or there is a bolt on housing you can get.

 

My W58 has made it almost a year with 450lbft of torque going through it... I think as long as you're not on super sticky/wide tires and you're not at the drag strip that trans would probably hold up just fine. I say this thinking that if you already have all the parts, why not? It costs a pretty penny to manual swap these cars no matter what transmission you use. I'd be tempted to get it in and give it a go!

 

Ultimate torque and sudden shock loading of torque over time is what eventually breaks the weaker transmissions with forced induction. A W58 surviving behind a turbo 2JZ or 1JZ totally depends on how that gearbox has been treated all its life, how much power is being put through it and how it is being treated.

I'd vote for an R150 conversion to do it right on a budget. Maybe an AR5 if it's affordable as R154's are starting to get costlier now.

Any manual conversion does add up for SC's and that's why I'd consider a stronger gearbox over a weaker one when more horsepower is desired. A stock 1992-1997 1UZ with no power adders is totally fine with a W58 but not with forced induction. Just as with a turbo JZ engine that transmission will be on borrowed time.

I second Ali SC3's notion: That the KA24 and W58 transmissions are only plentiful until they aren't. There are so many 300hp or less naturally aspirated projects out there for which those low torque transmissions are totally perfect and which will last all day long under the right amount of power.

 

I assume that's on your SC300, not the sold SC400? If so, that torque probably isn't coming on as early as it would with a 1UZ.

 

T2D2 - you're right I suppose... However, I think Craig nailed it... Drivetrain life (especially with upgrades/more power) is all about how you drive it. If you're going to flog it from a dig on sticky tires you're going to brake stuff, period. If you're going to do clutch dumps, burnouts, hard launches, rough gear changes, etc, it's all a matter of time. If you caress it and are gentler too it more often than not, then things tend to last a lot longer lol. Ask me how I know!

 

^ Agreed, but easier: a) said than done, and b) done when the torque curve isn't near-max at 1000 RPM like on the 1UZ. Also, it's tougher to drive a M/T gently off the line than it is an A/T, in my experience. If you feather the throttle at take-off, you're likely to either stall it or lurch. And who super/turbo's a car to not have fun with it off the line?

Add that all up, and I think you have to plan for the tough conditions of that much low-RPM torque in front of a transmission that will be straining to keep up, rather than hope for the best.