Borla No passenger side restrictor plate Vs medium plate

**Guerrillakilla13** · 02-03-2011, 06:57 PM

Hey everyone

I have a 02 WS6 with a Borla catback system. I like the sound of it, but i want it much louder. To be completely honest, the person before me (I just bought this thing less than a year ago) put on the Borla, so i have no idea what size restrictor plate is on the passenger side. I hear sound and feel air coming out of it though, so i know it isn't closed.

Does anybody know the difference of the volume for a open passenger side plate vs a medium to small sized one?

PS im new to the community, so hello

**INMY01TA** · 02-03-2011, 07:06 PM

Why not unbolt the flange and see for yourself? If there's a plate in there remove it.

**INMY01TA** · 02-03-2011, 07:13 PM

Ohh and I also have the Borla. There is a slight difference between open and the smaller plates but closing it up altogether makes the biggest difference (in the opposite way). Imo if you really want it louder than close it up altogether and put a cutout in the I pipe, this is what I run now. Much louder with an open cutout in front of the axle under the car. I have a DMH electric valve on it and can open/close it from inside the car. Ohh and welcome.

**Guerrillakilla13** · 02-03-2011, 07:15 PM

Originally Posted by INMY01TA

Why not unbolt the flange and see for yourself? If there's a plate in there remove it.

I want to, but i don't want to screw up the tips. the drivers side and passenger side are pretty even... thought i might kill off some time and stress by asking too.

**Guerrillakilla13** · 02-03-2011, 07:18 PM

Originally Posted by INMY01TA

Ohh and I also have the Borla. There is a slight difference between open and the smaller plates but closing it up altogether makes the biggest difference (in the opposite way). Imo if you really want it louder than close it up altogether and put a cutout in the I pipe, this is what I run now. Much louder with an open cutout in front of the axle under the car. I have a DMH electric valve on it and can open/close it from inside the car. Ohh and welcome.

hey Thanks man, and i was considering a electric cutout but i don't know where to get them for this specific borla system. Any tips?

Would an open cutout have the same volume as no restrictor plate?

**INMY01TA** · 02-04-2011, 04:39 AM

Unbolting the flange will not screw up the tips as it bolts back the exact same way. With the cutout I'm talking about putting it in the I pipe, before the axle, under the passenger seat. Doesn't need to be Borla specific there. Yes it will be louder there than an open Borla.

**Guerrillakilla13** · 02-04-2011, 09:51 AM

I just tried unbolting it.. whoever tightened it made it too tight, impossible to loosen. Couldn't do it. I might have to take it in to a shop to do it.

Sounds like a good idea man. Does it require you to cut part of the borla catback, or can it replace a certain part of the mid pipes?

Ps I appreciate the help

***Ed Blown Vert*** · 02-04-2011, 10:03 AM

This is what I run in my Borla

http://www.mccordcg.com/mpp/mpp.htm

**INMY01TA** · 02-04-2011, 06:21 PM

Originally Posted by Guerrillakilla13

I just tried unbolting it.. whoever tightened it made it too tight, impossible to loosen. Couldn't do it. I might have to take it in to a shop to do it.

Sounds like a good idea man. Does it require you to cut part of the borla catback, or can it replace a certain part of the mid pipes?

Ps I appreciate the help

It would go in the I pipe (part of the catback) that runs from the Y pipe to the muffler. Here's a pic from pajeff's car. Ohh and use a longer breaker bar and some PB Blaster on those bolts, they'll come out.

**peterlawl84** · 02-04-2011, 09:58 PM

I have a borla with an electric cut-out as well, but I put my cutout in place of the adjuster plates...I used to drive with the wide open plate, but it got too much unwanted attn after the H&C install, now I can have it closed for daily driving and then open it up when I want to have some fun.
I use the DMH cutout designed to replace the adjuster plates.
Also, the first time I tried swapping out the plates, it was a PITA to get the nuts and screws off, had to use some penetrating oil and a breaker bar

**sjsingle1** · 02-04-2011, 10:49 PM

i used no plate when i had stock exhaust manis on.......sounded perfect........when i got the long tubes it was to loud for me so i went back to the medium plate

**transam_00** · 02-05-2011, 09:02 AM

I dont know much about exhaust so maybe you guys can teach me a few things. Whats a restrictor plate? I dont plan on upgrading the exhaust until i do a engine swap in a year or 2 but what do you guys recommend?

**Cutlass** · 02-05-2011, 10:34 AM

The Borla Adjustable cat back system has a single 3 inch pipe coming from the y-pipe. That pipe goes up over the axle and then tees off so you can have dual outlets. One pipe exit each on the drivers and passenger side.
The drivers exit goes through a muffler. The passenger side is straight trough (no muffler). There's a joint there that you can install a resistor plate to adjust how much exhaust and sound comes out the passenger side. If you completely block it off, all the exhaust goes through the muffler and out the driver's side exit. There's also a plate with like a 1 inch hole and a 2 inch hole and there's the option to not run a plate at all (wide open noise and flow.)

**Guerrillakilla13** · 02-05-2011, 02:20 PM

Originally Posted by INMY01TA

It would go in the I pipe (part of the catback) that runs from the Y pipe to the muffler. Here's a pic from pajeff's car. Ohh and use a longer breaker bar and some PB Blaster on those bolts, they'll come out.

Thank you man, but i dont have that stuff i'll just have my muffler shop do it. And thanks for the pic, i thought about putting it in the I pipe but I think it would be better just to put it where the passenger restrictor plate is. Putting it in the "I" would just add a third tip, and on the right side only. I don't think it would work right nor make it as loud all around the car as i would want it to be..nor even look right haha.

Originally Posted by sjsingle1

i used no plate when i had stock exhaust manis on.......sounded perfect........when i got the long tubes it was to loud for me so i went back to the medium plate

I'm going in to the shop on tuesday or wednesday and i'm gonna have him help me out with the plates and perhaps some advice on where the cutout should go for maximum sound (his idea, not mine). What kind of headers do you have? I was seriously thinking about doing what you did, but the labor for headers are freakin expensive. If i can find good LT headers for a good price, i might do it.

Originally Posted by peterlawl84

I have a borla with an electric cut-out as well, but I put my cutout in place of the adjuster plates...I used to drive with the wide open plate, but it got too much unwanted attn after the H&C install, now I can have it closed for daily driving and then open it up when I want to have some fun.
I use the DMH cutout designed to replace the adjuster plates.
Also, the first time I tried swapping out the plates, it was a PITA to get the nuts and screws off, had to use some penetrating oil and a breaker bar

How do you like it putting the cutout there? Before the Heads and cam? Would you say its worth it? Damn your car must sound like a beast

**INMY01TA** · 02-06-2011, 05:43 PM

It's louder underneath (closer to the engine) shakes the whole car. Don't see it under there either. When you get a bigger cam it lopes harder from there, sounds more stockish coming out the back.

**peterlawl84** · 02-07-2011, 07:15 AM

Originally Posted by Guerrillakilla13

How do you like it putting the cutout there? Before the Heads and cam? Would you say its worth it? Damn your car must sound like a beast

I like the ability to adjust it from the driver's seat at will now rather than having to get under the car with wrenches. When it was stock, the wide open plate sounded great. After LT, it still sounded great, but was alittle loud and I would have to watch out for cops. After H&C, it was definitely too loud...had cops turning around in traffic to try and follow me.

I got the cut-out after the H&C, but in hindsight, I would of definitely liked it prior so that I could quiet it down if it was late at night or whenever.

While I'm sure the cutout in the I pipe might be a tad bit louder, it is definitely loud enough where I have my cutout, plus I have the option of running it with everything going through the muffler (which you can not do if it is in the I pipe).

Also for those that are curious, I ran the car on the dyno with the cutout open and closed, picked up 6 rwhp and 33 ft/lb torque with it open vs closed.

**Guerrillakilla13** · 02-08-2011, 08:22 AM

INMY01TA, I like the sound of that! But im gonna probably have to do what peterlawl84 said... just put the cutout where my restrictor plate is. It might not be as loud as i want stock, but i do get more control over how much air goes through the muffler (instead of through the passenger side tip) and how much doesn't.

Alright gentlemen, based on all of your help, i've made a decision. For now, i'm just going to get the restrictor plate removed once I'm due for an oil change (Which'll be pretty soon). During the summer time, when my work gives out tons of hours, i'm going to save up some cash and buy Pacesetter Longtubes with Pacesetter midpipes. Than MAYBE if its too loud, i'll get the cutout.

Thanks everyone for the help! Great community we got here.