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Discussion Starter · #1 ·
Decatted the car tonight...made a DRAMATIC improvment in power delivery....is very healthy up top and i even gains some more midrange torque via the butt dyno. There arent any emmissions laws here and it was only the one cat anyway. No O2 sensors behind it either 8) i love Toyota

Sorry i didnt get any pix of the piping with the cat in place but i left the camera in the car and we were already taking the pipe off, after we got the mid pipe off we lowered the car to get the camera.






The BLitz...the supposedly engine enamel burnt off so its back to its dull stainless self...staying that way.


Pipe being tacked into place


Tacking the other side


Took it down off the car to finish off the welds


Finished product


Again
 

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Discussion Starter · #7 ·
bgwillyBadassIS31 said:
there arent any O2 sensors behind the singly cat that the Altezza's do have.
 

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Discussion Starter · #9 ·
youre most welcome 8)
 

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RE:

Hmmm, what kind of setup are you running? Was your car stock or what? Reason asking is because I'm assuming you removed the catalytic converter and by running an open setup like that you might have lost HP.
Unless your running in the 350 RWHP range it won't benefit you. I lost alot of back pressure running with no cat which in turn lost some low end torque. At least that's how it was on my mustang.???


-Yamaha Dave
 

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Discussion Starter · #11 ·
you never want back pressure, it doesnt give you any low down torque....common misconception. You want high exhaust gas velocity. The smaller the pipe the sooner in the rpm range the "optimum" velocity is reached, hence why different exhaust sizes cater to different power bands. I havent lost any power that i can feel....the car is alot smoother now. It used to only pull really hard from 5500rpm now it pulls hard as hell between 4500 and 5000rpm, and pulls harder that it did before from 5000-7750.
 

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I thought the cat was on the y pipe. I might be looking at it wrong. Oh you got the alttezza and I got the IS300. Thats y.
 

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nice shit you pimp :chill:
 

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- thats illegal over here.. good luck finding an exhaust shop to do it :pissed:
 

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wdskuk said:
I thought the cat was on the y pipe. I might be looking at it wrong. Oh you got the alttezza and I got the IS300. Thats y.
altezza is a 4cylinder......4>>1?

is300 is a inline six.......6>2>1.

if it's 4>2>1...the y-pipe might be farther before the cat...
 
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