• From: San Diego, CA
  • Registered: 2011-11-26
  • Posts: 596

Re: Noise: or, put a muffler on that thing, buddy.

Cool thanks guys

The cherry bomb type is a bit longer 24" total.  We have an idea of where we are going to put it and the turbo muffler is 16" total  and should fit better.

We have been running the car pretty much on strait pipes with just a wide resonator tip.. but he muffler wont hurt us in anyway.. we cause enough of our own problems that if there is any hp loss it wont matter..

Plus - if  it is still alive I want to run it in the local SCCA Solo2s for fun next year and they are pretty tight on noise regulations.

5x loser - and just all around not very good
My Crappy Blog
Former Sex Pistons Craptain
And it feels so funny, like bathing in honey...

socal.colin's Website

  • From: Westfield Ma
  • Registered: 2012-10-29
  • Posts: 1,148

Re: Noise: or, put a muffler on that thing, buddy.

Harmonics of straight six's and fours cause the excessive noise and it's tough to muffle the noise vs a quiet v8's. 

I have trouble with my E30 M3 meeting exhaust and intake dB levels while on the track.

  • Dave
  • Dave
  • Effluent
  • Offline
  • From: PGH PA
  • Registered: 2009-10-09
  • Posts: 993

Re: Noise: or, put a muffler on that thing, buddy.

http://i1006.photobucket.com/albums/af184/zz4350supra/mufflers.jpg

OK, it is done. I put these stupid ass mufflers on to quiet down the Gremlin, So instead of hearing the Gremlin scream now it will only growl. I still don't know how it will sound FLAT OUT, because I can only run it FLAT OUT on the race track. big_smile

It Ain't My Fault

Dave's Website

  • Mulry
  • Mulry
  • Ayatollah of Rock-n-Rollah
  • Offline
  • From: Dallas, TX
  • Registered: 2009-05-01
  • Posts: 4,607

Re: Noise: or, put a muffler on that thing, buddy.

For what it's worth, I know of one car -- not mine -- that uses a bolt-on turn-down exhaust tip. Can't meet the exhaust dB level? Just clock the turndown 90 degrees. Wash, rinse, repeat.

Pat Mulry, TARP Racing #67

Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.
  • Dave
  • Dave
  • Effluent
  • Offline
  • From: PGH PA
  • Registered: 2009-10-09
  • Posts: 993

Re: Noise: or, put a muffler on that thing, buddy.

http://i1006.photobucket.com/albums/af184/zz4350supra/zoomies.jpg

But that would loose the cool factor

It Ain't My Fault

Dave's Website

56 Reply by Mulry (edited by Mulry 2013-10-25 09:46 AM)

  • Mulry
  • Mulry
  • Ayatollah of Rock-n-Rollah
  • Offline
  • From: Dallas, TX
  • Registered: 2009-05-01
  • Posts: 4,607

Re: Noise: or, put a muffler on that thing, buddy.

Dave wrote:

But that would loose the cool factor

I completely agree with you. We had some cool Monza resonator dual-tips on the end of our exhaust at Houston. They said it was too loud. We lost an hour on track cutting them off and welding together a replacment with a Supertrapp on the end. And the cool factor too. #sadtrombone

Pat Mulry, TARP Racing #67

Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.

57 Reply by TeamLemon-aid (edited by TeamLemon-aid 2013-10-25 11:14 AM)

  • From: Iowa
  • Registered: 2010-04-20
  • Posts: 2,660

Re: Noise: or, put a muffler on that thing, buddy.

I guarantee our 325es is more quiet than your car...

Spinnetti wrote:
dculberson wrote:

Yeah, a good rule of thumb is: if it's loud, put a real muffler on it.  It's not that hard to do.

Another rule of thumb is, if its a BMW with typical BMW drivers, its gonna be too loud (excepting Bucksnort wink

LemonAid - Changing kids lives one lap at a time.
  • From: San Diego, CA
  • Registered: 2011-11-26
  • Posts: 596

Re: Noise: or, put a muffler on that thing, buddy.

So... was this actually being enforced at Arese-Freeze Sonoma?   Because there were some really loud cars..  some to the point I could not hear my own motor over them till they were multiple corners away.

I don't care either way.. let us be loud or make us be quiet.. but we made our car quiet and others were rattling my brain like at any other race. 

Would like to make our car loud enough so i can hear it...  not to be loud just for the sake of it.

I noticed a lot of cars that i remembered being loud before that were nice and quiet as well...  so it was nice to know people were trying to follow the rules.

5x loser - and just all around not very good
My Crappy Blog
Former Sex Pistons Craptain
And it feels so funny, like bathing in honey...

socal.colin's Website

  • Registered: 2013-12-29
  • Posts: 79

Re: Noise: or, put a muffler on that thing, buddy.

Thrush 17655 works well.   I get mine @ Discount for about 30$
  It slows it down a touch as all mufflers do but sounds good and seem  to not change over time.

Add about 1 ft of tailpipe  behind the muffler.  Without the tail pipe the sound will be about 6-10DB higher for some reason.   And boom inside the car. The little section of pipe transforms the sound for some reason.
MM

Mike Ogren, Racing in Florida, GA. 
352 4288-983
.
  • Mr.Yuck
  • Mr.Yuck
  • Lemons Staff Stalker
  • Offline
  • From: Brookeville, Md.
  • Registered: 2013-12-09
  • Posts: 1,014

Re: Noise: or, put a muffler on that thing, buddy.

I'll chime in from a drag racers point of view, anything that dumps under the car is going to be loud. I drove a car for about 1/2 season w/ 3" dynomax's and dumps. It about killed me on a short 20 minute drive. Added tail pipes and it was wonderful. Compression also has something to do w/ the noise level. Cars w/ high compression are going to be louder, just how it is. My 70 440-6 Charger is about 11.25:1 w/ complete 3" exhaust and Summit welded mufflers, it is uncomfortable to drive in for more than a quick trip to the beer store. I had to wear ear plugs for a 110 mile round trip race I did last Oct. I'll be swapping mufflers or adding resonators soon. So if you are thinking about the Summit Brand welded muffler and have some power it's not going to be quiet. As for out Gen III F-bird build It will have complete exhaust all the way out back w/ a cheap turbo muffler. That should be good enough and isn't going to cost us much power because a 305 doesn't make much to begain with.

"get up and get your grandma outta here"
  • From: Westfield Ma
  • Registered: 2012-10-29
  • Posts: 1,148

Re: Noise: or, put a muffler on that thing, buddy.

90 degree turns facing the ground help but at some tracks these will contact the ground on our car due to location basically being at mid wheel base

  • From: KSAV
  • Registered: 2011-12-19
  • Posts: 180

Re: Noise: or, put a muffler on that thing, buddy.

Not sure how you all feel about Flowmasters, but my partner had the revelation one day that just about every clapped-out donk in the junkyard will have a set of them under it.  We got two almost-new 2 1/2" single chambers for $20.  We run 90 deg. turns that dump out each side in front of the rear wheels, and the 289 sounds pretty good, IMO.

Team Fairlylame
HumidiTT '14 IOE Winner
  • Baron
  • Baron
  • Lemons Staff Stalker
  • Offline
  • From: DFW
  • Registered: 2009-05-01
  • Posts: 2,408

Re: Noise: or, put a muffler on that thing, buddy.

A good article for those that are concened about half a horespower on a $500 car.

http://www.superchevy.com/technical/eng … 05phr_exh/

Team Lost in the Dark
Winner " I got screwed" and "Jay's dream car"
2012 Gulf region champs
  • From: Colorado Springs Co.
  • Registered: 2013-09-24
  • Posts: 807

Re: Noise: or, put a muffler on that thing, buddy.

Can say for sure that my 4" exhaust tip that exits in front of the passenger side rear tire on the Marlin WILL drag a smidge in hard dips at HPR.
You totally don't want the exhaust turning down 90 deg. in front of the axle. For one, the rules forbid it. Secondly, our rear axle temps went from off the 300 deg scale on the temp gauge and smoking the the lube out under great pressure to just staying at ~300 deg. with no smoke or issues after we dumped it out the side. Sounds better too.

Captain of the Speedholes Wrenching #365 1965 Rambler Marlin and owner of the "Cockroach 454 Chevy Bigblock". Collector Emeritus of awful crapcans.
Earned every finish with Blood, Sweat, Tears,  Smoked brakes,dead wheelbearings, two blower explosions, and a never-ending thirst for more fuel. Finished em all! Currently hiding in a secret base in the shadow of the "Race to the Clouds".
  • gunn
  • Lemons Staff Stalker
  • Offline
  • From: SF, CA
  • Registered: 2010-12-18
  • Posts: 1,011

Re: Noise: or, put a muffler on that thing, buddy.

I redid my exhaust on my tbird with a 5.0/302 after the last race to remove (and sell) the cats.
2.25" downpipes to a Y to a single 3" pipe out the rear. My original design had a single 13" cherry bomb in the 3" diameter section. With this resonator and two more 90 degree bends in the 3" pipe section, I was hoping it would be enough.

It sounded pretty good but IMO, it was too loud. If you stood directly behind it, the off throttle popping would almost hurt your ears. While it might have skated by TEO, I didn't want to push it. More importantly, my garage is aimed straight at the living room of my neighbor aka my-friend-who-lets-me-borrow-his-truck-as-a-tow-vehicle. I had to fix it.

The solution was to add a SECOND (no reason to remove the first one since I couldn't place the new muffler in its position) muffler: this time I added a baffled, multi-chamber muffler from flowmaster (the shortest one I could find with 3" center in-center out).
http://static.summitracing.com/global/images/prod/large/EDL-55721_HH.jpg

It doesn't sound as wicked anymore but I think I can get away with revving it in the garage in need be. The sound is much more of a growl and all the high pitched sounds are absorbed/cancelled out.

Knowing what i know now, with my size engine, the size of the pipe I installed, and no cats, I would have skipped the cherry bomb and gone straight to the flowmaster/equivalent.

With the single cherry bomb -- the camera squelches the audio.
https://www.youtube.com/watch?feature=p … 2b7cQfzfJE

With both mufflers
https://www.youtube.com/watch?feature=p … EkrtupOKjI

Myopic Motorsport's #888 Ceci n'est pas une Citron Thunderbird ("This is not a lemon" but a 1995 tbird w/ 93 V8 swap + shopping cart rear wing + engine mounted frito maker)
2017 Sears Pointless Organizer’s Choice
Frito Making Tbird from 2018 Sears Pointless Engine Heat BBQ - http://goo.gl/csaet4
  • Registered: 2013-05-08
  • Posts: 26

Re: Noise: or, put a muffler on that thing, buddy.

socal.colin wrote:

So... was this actually being enforced at Arese-Freeze Sonoma?   Because there were some really loud cars..  some to the point I could not hear my own motor over them till they were multiple corners away.

One of those cars may have been the 484 Luv.  On Saturday we had our exhaust crack just behind the headers, and split wide open.  We never got flagged for the noise, but we did get directed to the penalty box for dragging scraps of header wrap.  Once in the penalty box, the judges came down on us for the open header.  We fixed it overnight and were quiet again for Sunday.


To everyone planning to use a cheap "turbo" style muffler:  DON'T!

The ends of most turbo style mufflers are crimped onto the body, not welded.  It only takes one good backfire to open up a crimped seam and start directing exhaust gasses where they really shouldn't go.  It was one of these mufflers that caused our truck to be flagged for fire twice at Buttonwillow (one end blew out, we quickly welded it together, then the other end blew out). 

The bodies of most chambered (flowmaster-style) mufflers are welded, not crimped, and are much safer.  Autozone sells the "Thrush Welded", a decently quiet chambered muffler with a welded body, with 3" models starting around $40 - not much more than a cheap universal turbo muffler.  There are literally dozens of similar cheap knockoffs, all with welded bodies, that should all work fine and not blow out.  Remember, exhaust counts as safety equipment, there's no reason to cheap out on the muffler.

If you can get away with a cherry-bomb type muffler, more power to you.  We use a glasspack on the #282 4-cylinder and ended up having to add a baffle to the exhaust exit after getting flagged for noise in 2013 at T-hill.