If any of you could help me with some tips on my exhaust.

leostunts · Lexus Owner Joined: Apr 15, 2005 Posts: 4

If any of you could help me with some tips on my exhaust.

Lexus1993 SC400 with 132000 miles.
I left the 2 cats that are bolted to the factory headers and installed 2 straight pipes at 2.25 to the rear factory exhaust mufflers and thats all, pretty loud.
I removed the mid section cat and the 2 resignators.
K&N replacement air filter.

I went to the dragstrip last night and ran 10.355 in the 1/8th mile at 800ft above sea level 70.88 mph and my best in the 1/4 was 16.178 at 81.72 mph at a different track the next day at a very high altitude 2640ft. above sea level, even with the corrections maybe 15.80 or 15.70 .
and average 2.4 60ft.
I even removed the spare tire and 1/4 tank of gas 91 octane.
This car stock claims 15.2 or 15.4 in the 1/4 mile.
My max stall was I think 2000 rpm couldn't even burn rubber if I tried. I did do nice burnouts in the water box.
I believe I lost some bottom end torque from the exhaust setup?
I didn't get to test the car out in stock form.

Butt do you think because of the straight pipe and no cross over pipe would be the cause of this?

I do think theirs better mid and top end range.

And I did order a cross pipe 2.25 inch.

SICKIS300 · Posted: Tue Apr 26, 2005 10:12 am Post subject:

Well I'm no mechanic but it seems you have plenty of mid and high end torque to get you through a decent 1/4mi time. Maybe your just slow off the line like every other Lexus. But I don't think those exhaust mods will have that much of an effect on your 1/4mi time. I think you would need new under drive pulleys and a high end intake (or ECU), and headers to get a little more HP out of your SC. The only thing that would drastically help would be forced induction, yet its quite costly. I'm no SC expert so hopefully someone with a mod'd SC will come along and share some good insight.

~Chris

leostunts · Lexus Owner Joined: Apr 15, 2005 Posts: 4

Thanks for your opinion.
Forced induction is what I'm use too -
02 Subaru WRX 350 crank HP and a 04 Dodge SRT4 250 WHP.

I'll probably end up installing a turbo on this also, because NA mods still won't make me happy. Not enough hp levels if I did all the NA mods.

Are there any type of chip or reprogrammed ecu?
or possibly a turbo package?

leostunts · Lexus Owner Joined: Apr 15, 2005 Posts: 4

I found my answer.

Check this out to see the benifit of the crossover.

http://www.timskelton.com/valkyrie/tech/images/h_pipes.pdf