Looks great Tob!! :beer: For anyone who is following this thread, I'm going to be recording some before and after videos so others can do a sound comparison to the stock setup, will try to be somewhat scientific about it. After driving a 2012 Boss 302 a couple of months ago, I just couldn't get the thought of side pipes out of my head, so many thanks Tob for making them a reality!
Boss 302 Quad Pipes on a GT500
- Thread starter Tob
- Start date
Made it to my local welding shop to get another bottle of Argon. Big mistake. I've been itching for one of these so I laid my wallet on the counter and bought the best one they had (and my current one is no slouch).
I don't think I could ever go back to a FiberMetal non-auto darkening model that I used to use in the field. Having good gear really makes projects like this that much more enjoyable.:coolman:
I don't think I could ever go back to a FiberMetal non-auto darkening model that I used to use in the field. Having good gear really makes projects like this that much more enjoyable.:coolman:
So in my skimming of this long thread I believe you said the kit ford racing now offers has some kind of modification done already that you had to do yourself with the original kit?
Then what extra would I have to do to make it work on my exhaust?
Thats a pretty cool idea what you have done. The electronic cut outs would be a nice touch!
Heath, from a hardware perspective, you're right. I have the electric cutouts sitting in a box because even without the attenuation plates in place I don't think the car is obtrusive - at all. Just a mild, pleasant burble.
I've thought about this quite a bit lately. GT500 owners could add the modified Boss H section and add the cutouts, but not add the sidepipes. As I showed earlier, they contain a lawnmower size muffler inside them that really cuts down on the noise they emit from their polished tip. So by not adding the sidepipe and by utilizing a cutout such as that from QTP, you'd have blaring exhaust at your fingertips...:idea:
I've thought about this quite a bit lately. GT500 owners could add the modified Boss H section and add the cutouts, but not add the sidepipes. As I showed earlier, they contain a lawnmower size muffler inside them that really cuts down on the noise they emit from their polished tip. So by not adding the sidepipe and by utilizing a cutout such as that from QTP, you'd have blaring exhaust at your fingertips...:idea:
Ok, so time for my update to this thread! Tob did a great job of modifying my FRP Boss 302 H-pipe, turned it around right away, then Snoreastercane/Superstorm Sandy hit and ruined my plans to do the install (and did terrible damage elsewhere, not making light of that at all). Thankfully not much effect here in MD, so this past weekend I set to doing my install.. in a carport, in 40 degree weather. First time jacking up the car, so I put the front up on race ramps and jacked the pumpkin.
Safety First! and Second, and really anything else I could shove under the car to stop it from falling on me.
I followed the steps as previously listed in the thread - took the air deflectors off, tied up the pipes, loosened the exhaust clamps, slid pipes back, tied the modified H-pipe up into place. I measured once, measured again, rotated the piece, taped it up, measured again, bumped it, cursed, realigned and measured again, then finally made the cuts, getting a face full of stainless steel. I just had to fire the car up with no mufflers before I assembled everything. Listen to it here:
2012 GT500 no mufflers - YouTube
Tob's modified H-section slipped right up in place, no problems at all.
will continue in next post.
Safety First! and Second, and really anything else I could shove under the car to stop it from falling on me.
I followed the steps as previously listed in the thread - took the air deflectors off, tied up the pipes, loosened the exhaust clamps, slid pipes back, tied the modified H-pipe up into place. I measured once, measured again, rotated the piece, taped it up, measured again, bumped it, cursed, realigned and measured again, then finally made the cuts, getting a face full of stainless steel. I just had to fire the car up with no mufflers before I assembled everything. Listen to it here:
2012 GT500 no mufflers - YouTube
Tob's modified H-section slipped right up in place, no problems at all.
will continue in next post.
Got the side pipes bolted up - had to take the spacer out on the passenger side due to a length issue and a welded-on clamp on the sidepipe (this is a build issue with the sidepipe, not Tob's H-pipe). A couple more pictures of the system buttoned up. It's surprisingly hard to take good photos when your fingers, arms and back are practically frozen from being on a concrete floor for a few hours.
I ran it to start with without the exhaust disc, took a test run and had the passenger's side pipe tapping the floor on the underside, so I fixed that the next morning by rotating the pipe, and thought I'd put in the restrictor disc to start, but I drilled it out to 7/8". I found in my 3 minute test drive that with no disc in place the sidepipes were overwhelming the rear pipes, and making it tough to hear the supercharger whine.
Took me about 4 hours from start to finish - but there was a lot of time spent being extraordinarily slow and careful about jacking the car up, then measuring what felt like 20 times before taking the sawzall to the pipes. I'm no mechanic by any stretch of the imagination, so this is a weekend warrior-friendly mod. What's particularly interesting about the finished product is you can't see it unless you're down on the ground.
For anyone wondering how this sounds compared to stock - I've put together a video comparing stock, sidepipes with no restrictor, then sidepipes with a 7/8" restrictor.
Boss 302 Sidepipes on GT500 - YouTube
I have some more video also, but need to edit it a bit to allow for comparison. It's definitely a big difference from stock, and the best way I could describe it is the sound of the GT500 from the rear, with the sound of the Boss 302 from the side, the combination results in a very different and aggressive note that seems to wrap around the car. It feels like more also - there's more exhaust vibration through the floor, but in a good way, not an annoying way.
I do need to experiment with the restrictor disc opening size though - around 2000rpm is giving me a bit of a booming/droning noise, and at times it can sound a bit like an old truck on decelleration - from what I've heard on Bosses on youtube running different diameters, the size makes a big difference. I could see the QTP cutouts being an interesting option - run stock GT500 exhaust for regular driving, then open the sidepipes all the way. I should note my GT500 is a daily driver (3 hrs a day back and forth to work), with my 5 yr old son in the car 1/3 of that time, so I'm perhaps more sensitive to quality of sound rather than sheer volume.
Many thanks to Tob for making this happen, I am a huge fan of this type of experimentation :thumbsup::thumbsup:
I ran it to start with without the exhaust disc, took a test run and had the passenger's side pipe tapping the floor on the underside, so I fixed that the next morning by rotating the pipe, and thought I'd put in the restrictor disc to start, but I drilled it out to 7/8". I found in my 3 minute test drive that with no disc in place the sidepipes were overwhelming the rear pipes, and making it tough to hear the supercharger whine.
Took me about 4 hours from start to finish - but there was a lot of time spent being extraordinarily slow and careful about jacking the car up, then measuring what felt like 20 times before taking the sawzall to the pipes. I'm no mechanic by any stretch of the imagination, so this is a weekend warrior-friendly mod. What's particularly interesting about the finished product is you can't see it unless you're down on the ground.
For anyone wondering how this sounds compared to stock - I've put together a video comparing stock, sidepipes with no restrictor, then sidepipes with a 7/8" restrictor.
Boss 302 Sidepipes on GT500 - YouTube
I have some more video also, but need to edit it a bit to allow for comparison. It's definitely a big difference from stock, and the best way I could describe it is the sound of the GT500 from the rear, with the sound of the Boss 302 from the side, the combination results in a very different and aggressive note that seems to wrap around the car. It feels like more also - there's more exhaust vibration through the floor, but in a good way, not an annoying way.
I do need to experiment with the restrictor disc opening size though - around 2000rpm is giving me a bit of a booming/droning noise, and at times it can sound a bit like an old truck on decelleration - from what I've heard on Bosses on youtube running different diameters, the size makes a big difference. I could see the QTP cutouts being an interesting option - run stock GT500 exhaust for regular driving, then open the sidepipes all the way. I should note my GT500 is a daily driver (3 hrs a day back and forth to work), with my 5 yr old son in the car 1/3 of that time, so I'm perhaps more sensitive to quality of sound rather than sheer volume.
Many thanks to Tob for making this happen, I am a huge fan of this type of experimentation :thumbsup::thumbsup:
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I've yet to hear/see video footage that captured the utter greatness of the Boss pipes when the car wasn't moving. The unique growl they emit under load is completely different than when the vehicle isn't moving. Would you agree Tas?
Yea could we have a video of the car when its driving from both inside and outside the cabin? Also from the video there seems to be zero difference between having cut outs and not having cut outs. But yea there is a unique growl I guess added with the boss side exhaust. But then the drone you are talking about makes me cautious about this. I hate drone.
Totally agree, sound under load and at idle is very different. Took the car for a run at lunchtime today, got into it a bit - I wish I could rev the thing to 9000rpm instead of 6250, it sounds glorious under full throttle at higher revs.
http://www.youtube.com/watch?v=SnuVMEeGruc
http://www.youtube.com/watch?v=psub7nNS0r4
Drone may not be the right word, it's a little boomier than I'd want at constant throttle in 5th gear right around 2000 rpm with the windows up. I noted it more for observation than anything else, if it was annoying you better believe I'd be under the car again making changes, but I'm leaving it for a while to get used to the overall change. I've had drone before in a Vette, and that was awful and made my want to tear out my ears - this is not at all like that. It may be a side effect of the 7/8" opening, or it may be clean new exhaust piping, maybe I'm being overly sensitive, who knows. Not a big deal at all in my book.
The Boss guys seemed to see some difference between 7/8" and fully open, but I agree it's not evident at all under idle. I'm interested in playing with some other diameters and trying it with no cutout again to see what changes. That's the part I like about this, I can experiment to see what I like the sound of.
Feel free to ask for any requests for video - I'll see if I can grab some video from an outside flyby. I'd like to document the sound as best I can for anyone who might be considering this. I think just having the flexibility of the H-pipe is worth doing it - I could run the Boss sidepipes, or close them off again for rear only, or run the QTP cutouts with turndowns, or with different custom side pipes - seems like endless possibilites once the H-pipe is replaced, and with it being a factory piece with Tob's super-clean modification everything mates up properly, doesn't feel hacked together.
http://www.youtube.com/watch?v=SnuVMEeGruc
http://www.youtube.com/watch?v=psub7nNS0r4
Drone may not be the right word, it's a little boomier than I'd want at constant throttle in 5th gear right around 2000 rpm with the windows up. I noted it more for observation than anything else, if it was annoying you better believe I'd be under the car again making changes, but I'm leaving it for a while to get used to the overall change. I've had drone before in a Vette, and that was awful and made my want to tear out my ears - this is not at all like that. It may be a side effect of the 7/8" opening, or it may be clean new exhaust piping, maybe I'm being overly sensitive, who knows. Not a big deal at all in my book.
The Boss guys seemed to see some difference between 7/8" and fully open, but I agree it's not evident at all under idle. I'm interested in playing with some other diameters and trying it with no cutout again to see what changes. That's the part I like about this, I can experiment to see what I like the sound of.
Feel free to ask for any requests for video - I'll see if I can grab some video from an outside flyby. I'd like to document the sound as best I can for anyone who might be considering this. I think just having the flexibility of the H-pipe is worth doing it - I could run the Boss sidepipes, or close them off again for rear only, or run the QTP cutouts with turndowns, or with different custom side pipes - seems like endless possibilites once the H-pipe is replaced, and with it being a factory piece with Tob's super-clean modification everything mates up properly, doesn't feel hacked together.
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Wait so let me try and understand this correctly. If we have the cut outs in then that means the side exhausts are not working? And if we take the cut outs out then the side exhaust is having air flow through it? I thought they were electric cut outs meaning under low RPM they stay closed and high RPM they open up or am I not understanding this correctly? Or do the cut outs just block some of the opening hence the 7/8" thing being that 1/8" is left open for the air to go through.
I'm thinking I need to drive 15 miles to the only ford dealer near me with a boss LS to hear this stuff in person since I am very interested in doing this and the x brace.
I'm thinking I need to drive 15 miles to the only ford dealer near me with a boss LS to hear this stuff in person since I am very interested in doing this and the x brace.
The dedicated QTP Boss cutouts utilize a butterfly valve that can be completely open, shut, or somewhere in between. They don't vary (on their own) with rpm. The hole diameters that Tas is talking about are the diameter of the drilled hole on the factory attenuation plates.
If you go back a few pages and read it through you may get a better understanding. I have videos of the QTP valves in operation as well.
If you go back a few pages and read it through you may get a better understanding. I have videos of the QTP valves in operation as well.
The Boss H-pipe sends exhaust output to the rear and the sides all the time, it's like an H shape with an extra pipe out each side. The optional part is what you put between the sides of the H-pipe and each side pipe. The normal Boss setup has a flat metal plate between the H-pipe and the side pipe with a little teeny hole in it, allowing only a small amount of exhaust gas out the sides.
Some folks keep it stock, some remove the plate and run it open (Tob), some (me) make the hole larger (it's now a 7/8" sized hole instead of 5/16"), and some replace the plate with electric butterfly valves from QTP as Tob said, so they can open them up or close them off from the cabin with a switch. There's nothing that changes with RPMs, although theoretically that would be a cool idea to automatically open a butterfly valve fully at WOT.
Some folks keep it stock, some remove the plate and run it open (Tob), some (me) make the hole larger (it's now a 7/8" sized hole instead of 5/16"), and some replace the plate with electric butterfly valves from QTP as Tob said, so they can open them up or close them off from the cabin with a switch. There's nothing that changes with RPMs, although theoretically that would be a cool idea to automatically open a butterfly valve fully at WOT.
The Boss H-pipe sends exhaust output to the rear and the sides all the time, it's like an H shape with an extra pipe out each side. The optional part is what you put between the sides of the H-pipe and each side pipe. The normal Boss setup has a flat metal plate between the H-pipe and the side pipe with a little teeny hole in it, allowing only a small amount of exhaust gas out the sides.
Some folks keep it stock, some remove the plate and run it open (Tob), some (me) make the hole larger (it's now a 7/8" sized hole instead of 5/16"), and some replace the plate with electric butterfly valves from QTP as Tob said, so they can open them up or close them off from the cabin with a switch. There's nothing that changes with RPMs, although theoretically that would be a cool idea to automatically open a butterfly valve fully at WOT.
Isn't that what the zl1 and corvettes do? Or other tech advanced cars? When they say they have electronic exhaust?
So now I am wondering if the side exhaust only has the tiny hole for the air to flow through how does it sound? Also your 7/8" sized hole is how much bigger than the hole in that picture? Is it a little bit bigger or a lot bigger? Since that would effect the sound drastically I assume. Same as just letting it be open all the way. But maybe I'm thinking the QTP cut outs would be best and probably just put the switch underneath the dash to hide it.
He showed this on the previous page.
He's now at 14/16" and was originally at 5/16"...
He showed this on the previous page.
He's now at 14/16" and was originally at 5/16"...
Ah I see I didn't catch that picture. So I'm curious now why the boss has even side pipes if that cut out hole is so tiny. Do they just assume track people are going to remove them completely when on the track?
I provided the following link earlier in this thread. It explains the origin of the system and its intent...
Donald Farr's book.
Car and Driver goes into detail about the plates here.
5.0 Mustangs and Super Fords did a writeup on the QTP electric cutouts here.
And here's a short clip that kind of gives you a 'hands on feel' as to the factory hardware on a '13 Boss 302
http://www.youtube.com/watch?v=nlZUjfKK41M&feature=related
Donald Farr's book.
Car and Driver goes into detail about the plates here.
5.0 Mustangs and Super Fords did a writeup on the QTP electric cutouts here.
And here's a short clip that kind of gives you a 'hands on feel' as to the factory hardware on a '13 Boss 302
http://www.youtube.com/watch?v=nlZUjfKK41M&feature=related
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