rdm20fan

The times for my car posted above are correct 13.1 @ 113, and the a 13.3 @ 116
I have a autometer D-pic which when my SC was running it's best said a 12.8 @ 125
You can get your TC rebuilt for around $150, which is what all the other manufactures are doing. Suprastore.com sells the supra torsen LSD for $200 i think, but this isn't going to help most SC400's since tire spin isn't a problem.
The trans is what sucks at getting these cars to launch. I'm currently in the attempting to fit the Getrag 6-speed into my SC400.
I've seen bone stock GS400's run the 1/4 14.1

verylost

Could you tell me where I can find a mint, less than 1000 mile stock SC400? Most 10 year old cars do tend to slow down over the years.

You need to read those numbers within context. My car is 10 years old. My stock times were run on a cool night. My modded times were run in the middle of a 90 degree summer day. Even with conditions against me, I managed to cut off 0.8 seconds. Take the numbers as you will, but my stock times are the norm. Dig around these forums and you will find that the pre-98's run between 15.4 and 16.

However, I will admit that a naturally asipirated sc400 is not fast.

b1ackhawk

Your right, the LSD alone will not help a nearly stock SC, but an LSD w/ a lower gear, ie. 4.27, would definately help those 1/4 mile times!

b1ackhawk

I understand that old cars slow down a bit, clogged cats etc. but that sounds like alot. My acura was 8 years old when I picked it up, but only lost a tenth or two in the 1/4. Although I see here you said you were sleeping at the tree, so maybe a 14.7 or 14.8 is doable with your current setup. Dont get me wrong here, im not bashing you or anything, I just would not be happy if my car is running that much slower. I just realized that pre 95 was a tad slower in the 1/4, so that may account for some of it. Maybe someone out there has a 95-96 with 1/4 mile times?
Ive found as of recently that nice 98-99 GS400s are attainable for under $15K, I'd like to get close to the 1/4 mile time of this car, if its not possible, maybe I will go to GS400, I love the SC so much though, I dunno, just venting.

cip

Please allow me to compare a 'new' SC400 & a 10 year old one.

I bought my 1st SC400 in '94. It was an off-lease certified car w/ 28K miles. At that time I also test drove a '90 LS400 with more than 95K miles and that LS helped my decision to lease the SC...it ran perfect, idled, took off, turned, stopped, etc, better than other American new cars at the time (I know that's apples to rotten apples, but still )

I put over 60K miles on that car before totalling it, I now have a '96 SC400 w/ 91K miles on it and I can feel the extra 10HP / 10lb-ft TQ difference. The '96 has had all service done at the dealer and was done based on age, not miles, so the 60K was done @ 48K, the 90K was done @ 78K, etc.

There is no question, NO QUESTION, that if you want your 5, 10, 14 year old SC to run as good as it ran new, you will need to maintain it!! If you can't verify what was done, tehn do the following before you hit it w/ NOS, exhaust, turbo, supercharged, or otherwise expect it to perform better than it did when new:

-change ALL fluids (diff, trans, oil, coolant, PS, brakes, etc, etc.)
-replace engine mounts
-replace trans mount
-replace plugs, wires, rotor (with OEM or better)
-make sure it's ground properly
-replace o2 sensors (all 4)
-repalce timeing belt
-do a compression and/or leakdown test
-make sure injectors are good
-finally reset the ECU

Then run your car & begin your mods

b1ackhawk

Good advise, I still have to do my diff, coolant and brake fluids, and next project is a grounding kit. My AC light is flashing so I have to replace the compressor or clutch, easier to do both.

JBrady

While the official rating difference is 10hp/10tq the actual difference is closer to 25hp. The original engines were overrated power wise and make closer to 230hp flywheel. The SC400s all have the same very restrictive single tube exhaust manifold that costs is around 10hp vs the 95-00 LS400 and probably 20hp vs the 98-00 GS400.

b1ackhawk

So your saying the exhaust on the 96-97 SC400 flows better than 92-95, resulting in the bump in HP/tq?

JBrady

Let's first talk about the LS400 which the SC400 used the same engine except for exhaust manifolds. The 90-94 LS400's 1UZFE has 10.0-to-1 compression and single tube exhaust manifolds and was rated 250hp/260tq and typically dynojet at 175rwhp. In 95 compression increased to 10.4-to-1, the exhaust cam gained a small amount of duration and dual tube exhaust manifolds were used. Dynos for these years are around 200rwhp. Consider that the 95 LS400 was a full second faster 0-60 and in the 1/4 than the 90-94 models and using 22% as the apx drivetrain loss... gives the earlier 1UZFE a more accurate rating of 225-230hp. I believe that Lexus initially overrated the engine due to early dyno testing without full exhaust or intake plumbin in place and the tuning may not have been finalized. For the 95 model year LS400 the ratings jumped only 10hp officially but MUCH more in reality.

Considering the above, and considering that the 92-94 SC400 had the same engine except the exhaust manifolds were slightly worse, and considering the same basic dyno numbers is evidence that these years SC400s are really 225hp cars.

The real question comes in what happened with the 95 SC400 which kept the 250hp/260tq rating. I can say that it has the same early exhaust manifolds. I have not confirmed its compression of cam specs. This means one of 2 things, either Lexus used up the remaining early 1UZFE in the SC400s .... OR.... the 95 SC400 got the improved engine but with the lousy manifolds was still 10hp under the LS400. If anyone has a chassis dyno from a STOCK 95 SC400 we may learn the answer.

The 96 and 97 SC400s had the same rating as the LS400 but this again could be political rather than factual.

The 98-00 LS400 got the 290hp/300tq VVTi 1UZFE and that is accurately rated. The 98-00 SC400 also has the same engine and rating but still has the same LOUSY single tube manifolds. I bet most stock 98-00 SC400s dyno around 10hp shy of the LS400s due to this.

BTW, the dual tube manifolds fit the SC400 chassis and I have no idea why Lexus did not use them. If any one is interested I have a set of the dual tubes for sale. PM me if you want info.

b1ackhawk

Lets see those 1/4 mile times!

We should be proud of our SC400's, even if they do run 15's...

rdm20fan

My 93 stock ran a 15.8 @ 87 MPH
after I took off the cats, and ran dual 3" exhaust i ran a 15.7 @ 89MPH
I had 150,000 something miles on it

DoubleWhoosh

How would verylost's reaction time make his ET any better???

This is puzzling

ant1k

my stock 92' SC ran 16.1 at like 77mph prolly my slow reactions more than the car haha

b1ackhawk

Well he seemed to think it would.

chitwnsazn

iTrader: (3)

reaction times dont get figured into the et does it? you could sit there as long as you want and the clock would start only when you leave right?