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Thread: First post and an exhaust question for CA owners

  1. #1
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    First post and an exhaust question for CA owners

    Hello All,

    First time post, been a lurker for a few months reading build threads. I want to thank everyone for being such a great community. This is such a fantastic resource and is one of the reasons I am planning on a MK4 build with my son. The creativity, passion and willingness to share just blows me away. I am a total noob and will need all the help I can get. To me the Roadster combines so many things I love and am looking forward to sharing the journey with my 17 year old son. It’s a rare thing these days to have a kid who dreams about what he wants to build not buy and I definitely want to foster that.

    I am currently researching what I want on my build but one thing that is concerning me is the current change on how California law enforcement will now handle exhaust noise violations. With it no longer being a “fix-it” ticket (see AB 1824) but having a mandatory fine ($25-$1000 depending on who pulls you over) and possible referee inspection, I do not know how a Cobra replica with side pipes would be able to pass such an inspection without blowing the 95db limit. From what I have read the FFR side pipes are over 100db at idle.

    Have you CA owners being pulled over much in the past? How did you “fix-it” to get your ticket cleared? I am leery of spending 1-2 years on a build only to get a noise violation that cannot be cleared making the car unusable.

    I was thinking the Boig Quiet Pipes would be a good option combined with a healthy dose of awareness and mindful throttle control (always good idea anyway). Even so, these would not be quiet enough to pass a referee inspection if it ever came to that.

    Thoughts?

    Thanks!!!

  2. #2
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    Quote Originally Posted by Daddy O View Post

    I am currently researching what I want on my build but one thing that is concerning me is the current change on how California law enforcement will now handle exhaust noise violations. With it no longer being a “fix-it” ticket (see AB 1824) but having a mandatory fine ($25-$1000 depending on who pulls you over) and possible referee inspection, I do not know how a Cobra replica with side pipes would be able to pass such an inspection without blowing the 95db limit. From what I have read the FFR side pipes are over 100db at idle.

    I was thinking the Boig Quiet Pipes would be a good option combined with a healthy dose of awareness and mindful throttle control (always good idea anyway). Even so, these would not be quiet enough to pass a referee inspection if it ever came to that.
    Not a California resident, but spent a lot of quality time monitoring autocross cars for sound violations (if you need time to stall + research your own muffler problems / violations - take over the sound enforcement program - lol).

    Bottom line - It depends on how they measure it.

    California law appears to specify not to exceed 95db @ 50'.


    No typical sidepiped FFR roadster is going to exceed that at idle.

    Pretty much every 4 into 4 sidepipe roadster is going to exceed that when the following conditions are met: loaded engine + over 1/2 throttle + over 3500 rpm (typically 4000+rpm with heavy throttle = 95-100db, typically 5000+rpm with heavy throttle is headed for 100-105db).

    I seriously doubt a referee is going to go to that much trouble or know that much about it.


    Just for reference, your average "street tire squeal" is going to register 100-104db at 50 feet (braking or wheel spin).


    The only sound meter (totally) effective modifications I have found are augers in the sidepipes and or SuperTrapps.

    A good set of either will keep you real close to 95 at 5000+rpm / open throttle.

    Both combined will take it closer to 90 and below.


    I've seen a lot of people change sidepipe mufflers + still blow over 95 (in the above conditions).


    Again - it depends on how a referee measures it, but if you're below 3000rpm and below 1/2 throttle you should be golden with stock FFR sidepipes.


    Not to say it won't be rattling your neighbor's windows, but very safely below 95db measured at 50'...

  3. #3
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    I'm also in CA (SF bay area) so I share your concern somewhat. I say "somewhat" because (around here at least) it seems that the police's interest in you is directly related to how much of an a-hole you are in crowded places. My little town has a nice quaint downtown area with lots of restaurants and foot traffic. Lots of loud hotrods cruise all day during the summer. The only guys I see drawing any (negative) attention are the Harley guys that are revving their bikes while going 5mph down the strip. I would suspect that (around here at least) if you're not making a nuisance of yourself you'll largely be left alone.

    Now, all of that said, it's one of my goals once my roadster is finished to track it at least once or twice at Laguna Seca. They have VERY strict noise control there, with a 95db limit. Most folks end up having to ease up through the turn where the "sound police" are in order to not get black flagged. My plan is to run a set of GP Headers with built-in catalytic converters and Gas-N side pipes, and check my right foot (to the extent possible) and hope for the best.

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    Thanks for the replies. Looks like the referee is supposed to use a microphone 20 inches from tailpipe at a 45 degree angle. At 3000 rpm the max allowed is 95db.

    Dug a little more and I could be totally wrong but it looks like there is an exception if the car was made after 1967 and the original exhaust system is unavailable. In that case an aftermarket solution can be used if it mimics the original factory setup. So, if the supplied FFR pipes are based on the originals you would think it is all good? Not sure how they would handle a roadster built in 2019 but registered as a 1965. Ridiculous, feel like you need a lawyer to decipher this.

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    Quote Originally Posted by Daddy O View Post

    Looks like the referee is supposed to use a microphone 20 inches from tailpipe at a 45 degree angle. At 3000 rpm the max allowed is 95db.

    Ohhh, now I see - new law (or at least new angle of enforcement)...

    Further research here www.bobsmuffler.com + here https://jalopnik.com


    Ok, I've never measured one from 20 inches, but I'm guessing I would be lucky to pass that with augers + SuperTrapps installed, and most of the disks removed from the SuperTrapps (removing disks makes it quieter, adding back pressure).


    Not sure how they can (legally) go from specifying 95db @ 50' in state law to a referee measuring for 95 @ 20" @ 3000rpm (under the same law) - pretty sketchy.


    I'm going to go out on a limb (not really far) and predict that no currently manufactured sidepipe is going to pass that (short of adding augers + SuperTrapps) - not even close...

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    Member Dewey McBride's Avatar
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    I'm also in the CA Bay Area and to be honest, I won't give it a second thought. I'm running CAT's and GasN side pipes. They have a deeper rumble and don't draw too much attention unless you really jump on it. Unless you're showboating, you'll be okay. I have heard some Cobra's that are crazy loud. It might be a problem for them.

    To be honest, every cop that I've run into just wanted to talk about the car. It's also followed by the question, "How fast have you gotten it up to?"

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    I agree with Dewey. I'm also in the Bay Area and a Cobra owner. I've never had any issues with excessive noise.

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    Thanks Dewey and Bitten,

    Good to know your setups are not getting unwanted attention. If you have any details you can share with me about what headers, cats, etc you used it would be great. I am looking at using the Blueprint 306 or 347 with efi.

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    I have a Coyote with Gas-n. I have driven past plenty of police officers and I’ve been on the gas more than a few times. Never raised an eyebrow. That being said, there is an area near me with switch-backs that attracts the super bike clubs. The neighbors complain so often about the noise that cops post a sign that says Zero Tollerance for Noise Violations. If I drive through at area I’m usually coasting in neutral. Drive smart and you should be OK. Do doughnuts in a school zone......

    -Steve
    Mk IV #8901 - Complete kit, Coyote, TKO-600, IRS. Ordered 5/23/16, Delivered 7/14/16, First Start 8/13/17, First Go-Kart 10/22/17, Registered and Completed 10/18/18. Build Thread: http://thefactoryfiveforum.com/showt...V-Coyote-Build Graduation Thread: https://thefactoryfiveforum.com/show...-Roadster-8901

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    Senior Member RickP's Avatar
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    Daddy -0

    welcome to the forum. Take a look at Boig Quiet Pipes

    https://thefactoryfiveforum.com/show...ide-Pipe-Kits!

    or as previously stated, Gas-N-Pipes. The supplied FFR side pipes are extremely loud and only get louder with time. If noise level is a concern for you and the law, the Boig's may be the way to go.

  12. #11
    Member Dewey McBride's Avatar
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    Quote Originally Posted by Daddy O View Post
    Thanks Dewey and Bitten,

    Good to know your setups are not getting unwanted attention. If you have any details you can share with me about what headers, cats, etc you used it would be great. I am looking at using the Blueprint 306 or 347 with efi.
    I'm running a 4.6L DOHC, Ceramic coated OEM manifolds, Smiley’s Custom Headers -Custom J-pipe mods and ceramic coating, and CAT/J-Pipes with GAS-N sidepipes. I'm not sure how it'll sound if I removed the CAT's and went to regular J pipes. From what I've read, the CAT's don't really rob you of too much HP. I'm making about 350hp at the crank which is plenty. Traction can be an issue if I'm having fun...

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    Thanks! I have looked at the Boig website and Bobs post on here, beautiful work! I live in a pretty densely packed housing track on a small cul de sac so taking measures to make it reasonably quiet plus mindful throttle use sounds like a good way to go. It is a gamble with the new law, if in the slight chance you got a violation I dont see how a side piped roadster could pass a refereed noise check to stay below 95db measured 20” from pipe at 3000 rpm.

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    Quote Originally Posted by Daddy O View Post

    It is a gamble with the new law, if in the slight chance you got a violation I dont see how a side piped roadster could pass a refereed noise check to stay below 95db measured 20” from pipe at 3000 rpm.
    I will do some further testing and report back as soon as the weather moderates (soon, hopefully).

    In the meantime I found this, not sure where exactly the sound meter was, but almost certainly beyond 20" + 45 degrees.

    https://www.youtube.com/watch?v=ZZJ1oi9jJxc

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    Quote Originally Posted by mike223 View Post

    I will do some further testing and report back as soon as the weather moderates (soon, hopefully).
    I got to do some testing today - some came out better than I expected, some worse.

    I have a lot of long term data on my car - ran autocross sound enforcement for an scca region for ~5 years.

    Took the program over on the basis of "you can't call us "good" at one event, not bother to run sound next event, and then DNF my runs on a third event because I'm (now) "too loud" - you can't convince people to modify their exhaust if you can't produce repeatable results.

    Turned out it's all about meter location, and you don't always have a perfect straight to catch people on in your average autocross - you need to catch people when they're "howling" (5k-6k rpm) past at high throttle - Different cars, different gearsets, different driver approaches - pretty challenging to produce repeatable results, but I did better than anyone ever had previously (or since).

    All my prior data was *only* concerned with measurements going past the meter "howling" @ 50' (back to "I never measured one at 20").



    393w, 10.5:1 compression, 4 into 4 headers, stock FFR sidepipes.

    At idle, I walked the (calibrated + double checked) meter around a 20-24" radius from the turnout - 83-87db. (better than I expected)

    Repeat at idle set to 3k - 99-101db. (again, better than I expected)


    Took stock turnouts off - installed custom turnouts with 4" SuperTrapps with 12 disks installed.

    Idle: 82-83db - 3k rpm: 99-100db. These are (supposedly) rated for 250hp each with 6 disks installed (maybe I'll test that another day, see below).


    Reinstalled stock turnouts and augers of my own design (which I probably ought to copyright, 5 years of design, research and all, sorry - no pictures are forthcoming, unless somebody wants to help make me a buck or three, lol).

    Idle: 82-83db - 3k rpm: 99-100db.


    Reinstalled SuperTrapps (12 disks) with the augers.

    Idle: 80-81db - 3k rpm - 98-99db.



    So here's the rub - I know for a fact that with this specific set of SuperTrapps + augers I can howl (50') past sound (open throttle, loaded) and never exceed 90db.

    More like 86-89db tops (sound guys get bored when you're under 90db).


    So I can state with a great deal of certainty that Kaliforna's enforcement program - a "referee" looking for 95db @ 20" @3k rpm...


    Has absolutely nothing to do with these cars and the current state law of 95db @ 50'.


    No currently manufactured sidepipe will pass this test - with the possible exceptions of catalytic converter and turbo equipped cars (very little experience with this).

    Good Luck - best be nice to the cop, and take care not to make a nuisance of yourself.


    Or find a lawyer (shark) who understands what I'm talking about...

    Because state law has nothing to do with their stated "referee" program.

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    I am also in California and will state what others have said. First, do not drive like a jerk or better said, do not drive to get the police attention. Leave that to Mustangs. I just bought catalytic converters for my car. Just to quite down the exhaust a bit and so that I do not have to smell untreated exhaust. Growing up, I liked that smell. Now that I am older and not used to it anymore, I just do not want to smell gas anymore.

    What scares me about AB 1824 is that noise not measured, but is up to the officer. If the car is tested by the referee, and found to be compliant, you still have to pay the fine.

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    Senior Member Avalanche325's Avatar
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    How loud your car is has a huge amount to do with the engine. High HP and especially a radical cam is going to crank up the volume. You can start by not having the loudest engine in the first place. Then go from there.

    The Boig Quiet pipes or under car exhaust are apparently the quietest options.

    I have wondered about a shorty race muffler in the straight part of the 4 into 4 headers. I quess that is pretty much what running cats is doing. Even with Flowmasters (no longer made), my car is very loud. Flowmasters were the best quiet it down without robbing HP option.

    Augers and inserts are an option to take an existing system down a bit. Again, typically a hit on HP.

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    Turbo it and call it a day lol. Although turbos quiet down exhaust noise levels a lot till the waste gate opens. As others have said noise is partially dependent on the motor. Also as stated you can get quiet pipes if needed but they kill hp. My recommendation is to run the car as a go kart with the FFR pipes that come with all the kits and have it checked, then go from there if there is a issue.
    Mk4, Moser M88 rear end, Eaton truetrak, Craft Racing 461 Windsor, MMR pro trans, Glenn’s 1,000 hp cobra fuel system and lots of other parts.

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    Lots of great info here, really appreciate all the feedback!

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    Senior Member KDubU's Avatar
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    Interesting read about the new noise law in CA. Not sure who it targets but around my way it’s the Harley’s that are the issue. First they almost always are in a group, multiple bikes with straight pipes are multipliers in noise. Then whenever they get to a light or stop sign they have to revved their bikes, not really needed but they do it anyways. Don’t get wrong, I like bikes and used to ride but there are ways of doing it so you don’t bring attention to oneself and the same is for the roadster. It’s already a head turner just sitting there, driving aggressively will get a lot more attention and the type you don’t need.
    Kyle

    Complete Kit pickup 09/05/2015, 351w, QF680, 3.55, 3-Link, 15" Halibrands with MT's, Painted Viking blue with Wimbledon white stripes on 03/15/2017. Sold in 08/2018 and totally regret it.

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  23. #20
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    I have not heard of any issues from the 95 db law. I notice not one "let me tell you about my ticket" post yet. Please add it if you have! It looks like the big deal is it forces a fine (cal needs the money). Will this help the police to start pulling over people?? I hope it ends up being one of the "you were being an idiot and besides the other tickets, go get the exaust checked!"

    I say do not worry about it, they wont, because in a few years cal will not have gas powered cars anyway! I wonder what they will think up to get extra cash out of tesla owners???
    Honestly, any one pulled over for noise? Please post.

    https://www.sacbee.com/news/politics...223367915.html
    This is the newspaper from the ca capitol. Read this if you want to feel better about your state!
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    LOL, Ok I’m sorry but I think it’s time for California to break away from the continental USA, drift out into the ocean and start there own country. Im all for reasonable regulations like noise limits at late hours. It’s when people make laws just to make them or because they just don’t like or understand some thing that it becomes out of control. I lost the last bit of any respect for California when they put noise limits and a check booth at Laguna race way. It’s a RACE TRACK let people enjoy there sport race event or not in a safe environment. Even though they finally repealed it last year I still shake my head.. This is like when people put homes near a existing sporting club or private airport then complain about noise and want them to shut down. Pretty soon you’ll be ticketed just because your presence offends some one. Unless that’s already a California law.
    Last edited by GFX2043mtu; 02-01-2019 at 07:29 PM.
    Mk4, Moser M88 rear end, Eaton truetrak, Craft Racing 461 Windsor, MMR pro trans, Glenn’s 1,000 hp cobra fuel system and lots of other parts.

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  26. #22
    25th Anniversary #9772 toadster's Avatar
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    has anyone sound tested a coyote with FFR pipes with the built in cats?
    Todd
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    17 years of driving and not a single complaint from anyone, not even the law. Usually it is along the lines of "It sounds good". I got radared once and the CHP said "We heard you before we saw you." with a smile.

    The real issue is your own hearing. I put Car Chemistry Inserts in mine even though I have catalytic converters. It was just too loud for daily driving. It's still loud, but it only sets off alarms from 50 feet now instead of 150 yards.

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    Senior Member SJDave's Avatar
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    Quote Originally Posted by JohnK View Post
    I'm also in CA (SF bay area) so I share your concern somewhat. I say "somewhat" because (around here at least) it seems that the police's interest in you is directly related to how much of an a-hole you are in crowded places. My little town has a nice quaint downtown area with lots of restaurants and foot traffic. Lots of loud hotrods cruise all day during the summer. The only guys I see drawing any (negative) attention are the Harley guys that are revving their bikes while going 5mph down the strip. I would suspect that (around here at least) if you're not making a nuisance of yourself you'll largely be left alone.

    Now, all of that said, it's one of my goals once my roadster is finished to track it at least once or twice at Laguna Seca. They have VERY strict noise control there, with a 95db limit. Most folks end up having to ease up through the turn where the "sound police" are in order to not get black flagged. My plan is to run a set of GP Headers with built-in catalytic converters and Gas-N side pipes, and check my right foot (to the extent possible) and hope for the best.
    Laguna is now 90 db limit....very tough to make under throttle. My 2005 BMW M3 with stock exhaust winding up in 3rd past the microphone booth hits about 93 db. So I have to short shift to 4th and lug past the microphone. I just did a track day at Sonoma Raceway with the Shelby Club, 95db limit. Microphone is on the right going up the long front straight just before the kink. I was able to give it almost full throttle past the microphone but my buddy got black flagged with stock FF sidepipes. My FF side pipes are heavily modified. I cut them just before the neck down to 3" for the tip, welded in Vibrant band clamp flanges so I can take them apart and modify easily. I removed the 2" diameter FF perforated inner tube and replaced it with a 3" perforated tube. I used woven stainless steel gauze around the baffle then 1/2" of ceramic wool packing. For Sonoma I installed one Dynatek Auger insert, I can install two. Each insert probably robs 20 HP above 4500 rpm, no free lunch....but I can run at both tracks with a little bit of backing off at the microphone positions.

    I tried Car Chemistry inserts in the header tubes, it really killed any power of the engine...not practical.

    If I was to start over, I would just get regular steel FF sidepipes, modify like I did, then get them black or silver ceramic coated. Stainless are a pain to keep looking nice if you track the car and get them really hot all the time. I get a Xmas card from Mothers Aluminum Polish after 9 years of using a ton of it.

    I am thinking about making some new tips that reduce to a 2" pipe and orient them to point under the car. Get some custom pipes made to route them under the car along the 4" frame rails, under the IRS, to a muffler attached to the rear bumper. Maybe I'll get to it this winter when I'm not enjoying the car so much!
    Attached Images Attached Images

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    Senior Member BEAR-AvHistory's Avatar
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    Quote Originally Posted by Daddy O View Post
    Hello All,

    First time post, been a lurker for a few months reading build threads. I want to thank everyone for being such a great community. This is such a fantastic resource and is one of the reasons I am planning on a MK4 build with my son. The creativity, passion and willingness to share just blows me away. I am a total noob and will need all the help I can get. To me the Roadster combines so many things I love and am looking forward to sharing the journey with my 17 year old son. It’s a rare thing these days to have a kid who dreams about what he wants to build not buy and I definitely want to foster that.

    I am currently researching what I want on my build but one thing that is concerning me is the current change on how California law enforcement will now handle exhaust noise violations. With it no longer being a “fix-it” ticket (see AB 1824) but having a mandatory fine ($25-$1000 depending on who pulls you over) and possible referee inspection, I do not know how a Cobra replica with side pipes would be able to pass such an inspection without blowing the 95db limit. From what I have read the FFR side pipes are over 100db at idle.

    Have you CA owners being pulled over much in the past? How did you “fix-it” to get your ticket cleared? I am leery of spending 1-2 years on a build only to get a noise violation that cannot be cleared making the car unusable.

    I was thinking the Boig Quiet Pipes would be a good option combined with a healthy dose of awareness and mindful throttle control (always good idea anyway). Even so, these would not be quiet enough to pass a referee inspection if it ever came to that.

    Thoughts?

    Thanks!!!
    Also depends on the engine. I have FFR pipes on the Coyote & they are pretty quite unless you are under load. Then they are very sharp & will set off car alarms. I believe its because of the variable cam timing.

    Guys complain they can't hear a radio at road speeds. AS long as the engine is not loaded & I am crusising I am good to 60-65MPH. What kills the radio is wind noise not the side pipes.

    https://youtu.be/_fJysY168Zk

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  30. #26
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    Quote Originally Posted by SJDave View Post
    Laguna is now 90 db limit....very tough to make under throttle.

    For Sonoma I installed one Dynatek Auger insert, I can install two. Each insert probably robs 20 HP above 4500 rpm, no free lunch....but I can run at both tracks with a little bit of backing off at the microphone positions.

    I am thinking about making some new tips that reduce to a 2" pipe and orient them to point under the car. Get some custom pipes made to route them under the car along the 4" frame rails, under the IRS, to a muffler attached to the rear bumper. Maybe I'll get to it this winter when I'm not enjoying the car so much!
    You are close.

    I never saw any significant observed reduction from clocking the turnouts (under the car, or any other direction - it's been tried).

    But if you made yourself a pair of turnouts with 4" SuperTrapps in the ends...

    You'll almost certainly stay under 92 - probably under 90 with the augers additionally - at 50' / 5000rpm / heavy throttle.

    4" Supertrapps are *supposed* to support 250hp "each" - I run mine with 12 disks, rather than the standard 6 (remove disks to quiet it down if necessary).


    Here's what gave me the inspiration:

    nick rescino2.jpg

  31. #27
    Senior Member weendoggy's Avatar
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    Quote Originally Posted by SJDave View Post
    Laguna is now 90 db limit....very tough to make under throttle. My 2005 BMW M3 with stock exhaust winding up in 3rd past the microphone booth hits about 93 db. So I have to short shift to 4th and lug past the microphone. I just did a track day at Sonoma Raceway with the Shelby Club, 95db limit. Microphone is on the right going up the long front straight just before the kink. ...but my buddy got black flagged with stock FF sidepipes. My FF side pipes are heavily modified. I cut them just before the neck down to 3" for the tip, welded in Vibrant band clamp flanges so I can take them apart and modify easily. I removed the 2" diameter FF perforated inner tube and replaced it with a 3" perforated tube. I used woven stainless steel gauze around the baffle then 1/2" of ceramic wool packing. For Sonoma I installed one Dynatek Auger insert, I can install two. Each insert probably robs 20 HP above 4500 rpm, no free lunch....but I can run at both tracks with a little bit of backing off at the microphone positions.
    That sound at Sonoma was 103, not 95. I run my Cobra there and it blows a 96. This time it was the Mustang and it blows a 95 and I didn't get flagged. I know a friend who did get flagged at 107 because he forgot to close off his "flapper". Laguna is 90, 92, 95 or more depending on day, event, etc. We've been there together. Trying a set of pipes I made this year even though we'll have a 103db day on Black Friday. I just want to see what they are so I know. Hoping for a 92db with them.
    I'm just a victim of a thousand physic wars!
    www.weendoggy.com/cobra.htm

  32. #28
    Senior Member SJDave's Avatar
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    Quote Originally Posted by weendoggy View Post
    That sound at Sonoma was 103, not 95. I run my Cobra there and it blows a 96. This time it was the Mustang and it blows a 95 and I didn't get flagged. I know a friend who did get flagged at 107 because he forgot to close off his "flapper". Laguna is 90, 92, 95 or more depending on day, event, etc. We've been there together. Trying a set of pipes I made this year even though we'll have a 103db day on Black Friday. I just want to see what they are so I know. Hoping for a 92db with them.
    Hey Glenn,

    I thought it was 95!! Heck I could have gone full throttle past the microphone! Wow, I surprised Freddie got black flagged if it was 103....his packing must be gone in his sidepipes by now.
    I didn't know Laguna had different levels except for special race days...every group I go with HOD, NCRC, Speed SF...is 90 db now. I know that the Shelby club gets a higher limit for the Turkey shoot, but that's their only event at Laguna...and it can be very cold that day after Thanksgiving!!

    What did you try with the new pipes?

  33. #29
    Senior Member weendoggy's Avatar
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    Haven't tried the pipes yet. May take them to Laguna if I take the Cobra. Might have the Mustang though because brother and daughter want rides. Last time I took the Cobra it was 36deg at 1st session but I was totally comfortable with heater and heated seats! Car ran great!
    I'm just a victim of a thousand physic wars!
    www.weendoggy.com/cobra.htm

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