Hi all.
I'm biting the bullet, in the process of ordering a new OEM Mid Pipe (front pipe) for my '08 GS 350, this includes two Cats', heat shields and the resonator. I'm also seriously considering removing the old and installing the new D.I.Y. in my garage up on ramps.
My question: has anyone tackled this project D.I.Y.? I've replaced exhausts in the past, this looks fairly easy and straight forward.

 

Are you catalytic's bad? Is it because the pipes are rusted that you want to replace the whole thing? Isnt OEM close to 2 grand?

Magnaflow has a system that may save you some money http://www.ebay.com/itm/Magnaflow-Ca...lVkFr2&vxp=mtr

 

Yes.. Pipe is rusted, many holes patched.. Exhaust smells of sulfur when I stuff my foot in it, no matter what fuel I run. No codes, but its time to replace.
Actually, the mid pipe (front pipe) is $1400.00/Shipped OEM/Factory includes two cats, pipe, heat shields and resonator to the axel back. I researched Borla, Tanabe, Magnaflow and Invidia, it seems most mid pipes if not all do not come equipped with cats or a resonator. I'm not really interested in changing the characteristic sound of my GS, its a 6 cyl. and no matter what its always going have that sound of a six. If it were an 8cyl, ports opened with a cam, then perhaps that would be the sound I would look for. Besides there are really no performance gains with an aftermarket exhaust unless there are modifications done to the intake and/or ECU (more air out means more air in and visa versa).
I can't not run without cats where I live, its unlawful and will not pass emissions test, then the real trouble begins. I'm not willing to take that risk.

 

http://www.ebay.com/itm/Magnaflow-Ca...lVkFr2&vxp=mtr
I believe thats for rear wheel drive, mine is AWD.. The front of the pipe would need fabricating..

 

Ill be very interested to see someone tackling this themselves for the 3GS AWD. Here up north, we have very leaky exhausts!

 

Actually, when done right, the 3.5L can sound really nice and clean. Some videos out there are almost GTR-like. Most of them are the 4GS with the Joe Z setup, but I'm sure the 3GS would be similar. But, I completely understand where you're coming from... I put an aftermarket exhaust on my GS460, then had it removed only a few hours later, haha. Either way, keep us posted when/if you decide to tackle this on your own.

 

I'm thinking to get that GTR sound their running without Cats and resonator. I would like to run clean pipes to the axel then some Borla or Magnaflow exhaust. I really need to stay legal, I have an emissions test coming up.
I pinged the ebay link above, they celarly stated that they do not have a direct fit front or mod pipe for the AWD.. Currently, I have no choice but to go the OEM route. I'm very comfortable with the Factory OEM pipe, I know its designed for the car. Not my first choice.
I'll let you all know if I tackle this on my own! Looks like I'm going to, so I look cool in front of my girlfriend, full of grease and debris.

 

pbxcomm - I'm in illinois and running with modified Invidia midpipe to fit AWD, CAI, and no issue on passing the emission test.

 

How much modification was needed to direct fit your AWD? Was it cost effective? I would be interested in your input in regards to he change in sound. Any performance gains without other modifications?

Thanks..

 

All the AWD cars have the rusting mid pipe. Its caused by the heat shields (Rust Catchers). There is no need to replace the entire $2000 Lexus mid pipe. Rockauto sells the repair parts for the AWD exhaust. Just $160 each side.

https://www.rockauto.com/en/moreinfo...434545&jsn=301

https://www.rockauto.com/en/moreinfo...434545&jsn=302

 

Are those all the actual peices of heat shields? Wow... How difficult was it to remove them all?

 

Good find.. But,, I've heard and read nothing but bad reiews about Davico's cats, fit, finish and they last less than a year if your lucky.. I also spoke with a local mechanic (of 30 years) and he stated the same, to stay away from Davico, thier warranty is also non-existant.
So, because my GS is AWD, my searching is narrowed to OEM. I've looked at other options and by the time I paid a shop to perform the correct modifications (welding and/or bending), installation, I'm up around $1000.00..
I can purchase an OEM front/mid pipe with cats and resonator specifically for the GS AWD for $1400.00 free shipping/no tax. I know if I keep the underside clean this should last at least 8 more years, although I don't plan on keeping the car that long (looking for a 2013 soon)! After which, I'll most likley go with the magnaflow/axel back.

Why didn't I buy a RWD!!!! Oh well..

 

You have a link to that part for 1400?? Thanks.

 

Yes, they are easy to remove. They just about fall off. Some genius engineer put fiberglass mat between the shield and the pipe, I guess to prevent rattles. Problem is it traps the moisture in there, and the road salt we use on roads up north in the winter. The pipes rust and get paper thin. Too thin to weld, my MIG welder just blew holes in the pipe. So now I'm looking at options to replace the mid pipe. Nobody makes an aftermarket mid pipe for AWD. List price from Lexus is $2,140 plus the gaskets, which are expensive. And its HUGE, doesn't look easy to ship.

 

ok should I be removing the heat shield in front of the o2 sensor where it snakes up into the engine?