Megaphones, for track use |
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Megaphones, for track use |
Trekkor |
Jul 4 2006, 11:46 PM
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#1
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
I like really LOUD open exhaust. Who doesn't? (IMG:style_emoticons/default/cool_shades.gif)
with the exception of Laguna, the the Db limit is 103. My SIX goes to 7300 rpm's. How loud will it be? I'm planning on making a set. (IMG:style_emoticons/default/dry.gif) Any ideas? KT |
Heeltoe914 |
Jul 5 2006, 01:18 AM
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#2
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Senior Member Group: Members Posts: 1,135 Joined: 31-January 06 From: Tujunga Calif, Member No.: 5,506 |
I have a used two bolt set that worked great on my 3.2 with 1 3/4 headers. Its sounds like a race car should. LOUD as all get up. But at the same time so sweet.
will sale 50 for set. |
Trekkor |
Jul 5 2006, 07:59 AM
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#3
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
I want them...
Can I see a picture? KT |
Trekkor |
Jul 6 2006, 11:42 AM
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#4
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
I was wondering is there any danger to the engine, specifically the valves, when running an open exhaust? Cool air rushin back to the valves and warping, bending etc?
Thanks, KT |
redshift |
Jul 6 2006, 11:50 AM
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#5
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Bless the Hell out of you! Group: Members Posts: 10,926 Joined: 29-June 03 Member No.: 869 |
Not that I have ever heard of. Only time I know that is a problem, is with a leak at the head.
I got a set of phones with a /4 I bought once, and we put them on, and went driving around Miami for a day... and only got pulled over once. (IMG:style_emoticons/default/laugh.gif) M |
slivel |
Jul 6 2006, 11:54 AM
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#6
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Old car....... older driver Group: Members Posts: 510 Joined: 10-July 04 From: San Diego Member No.: 2,332 Region Association: Southern California |
I was wondering is there any danger to the engine, specifically the valves, when running an open exhaust? Cool air rushin back to the valves and warping, bending etc? Thanks, KT There is a fair chance that your mixture will need to be richened if you uncork the exhaust. I typically go up one jet size on my mains (Weber 46's) when I go from mufflers to open pipes. Steve |
Joe Bob |
Jul 6 2006, 01:23 PM
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#7
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
My seat of the pants dyno on my 2.0/6 S motor found a significant loss of bottom end power....
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grantsfo |
Jul 6 2006, 01:34 PM
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#8
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Arrrrhhhh! Group: Members Posts: 4,327 Joined: 16-March 03 Member No.: 433 Region Association: None |
Good! I need to be able to hear what you are doing if I ever get out on the track with my car. Note people will also hear your mistakes a little easier too.
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jgara962 |
Jul 6 2006, 01:36 PM
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#9
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Yo, this is how I roll Group: Members Posts: 823 Joined: 5-April 05 From: Napa, CA Member No.: 3,879 Region Association: Northern California |
My seat of the pants dyno on my 2.0/6 S motor found a significant loss of bottom end power.... (IMG:style_emoticons/default/agree.gif) I put on a GT style open exhaust on my car. Just driving around, I can tell a difference in a lack of low end power vs the Birsch. But man, does it sound bitchin'! (IMG:style_emoticons/default/aktion035.gif) |
Trekkor |
Jul 6 2006, 08:56 PM
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#10
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
Yes, the sound is important too. (IMG:style_emoticons/default/smile.gif)
I don't think low end will be an issue as I am at 4500 rpm's and above on track. ( am I wasting my time? ) KT |
J P Stein |
Jul 6 2006, 09:10 PM
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#11
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
You'll loose mid range power due to the loss of the ballance tube effect of a properly
engineered muffler. You want noise? Do a GT engine lid & remove your rear window....trust me. |
Randal |
Jul 6 2006, 09:16 PM
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#12
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Advanced Member Group: Members Posts: 4,446 Joined: 29-May 03 From: Los Altos, CA Member No.: 750 |
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campbellcj |
Jul 7 2006, 01:00 AM
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#13
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I can't Re Member Group: Members Posts: 4,550 Joined: 26-December 02 From: Agoura, CA Member No.: 21 Region Association: Southern California |
Yep the midrange can drop; however you might pick up significant power at the top-end. If you keep the revs in the meat of the powerband then there is no problem. For autocross it would be problem if you have to hold a particular gear to avoid a shift and need to pull cleanly from low revs but this is not typically an issue on the track. FWIW my car seems to pull much better up top with the megaphones than the Dansk sport muffler...
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Root_Werks |
Jul 7 2006, 07:31 AM
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#14
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Village Idiot Group: Members Posts: 8,338 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
Some have already said it, you'll loose the cross extraction you have now. Which means less torque. Unless you run above 6000rpms all the time, leave the muffler on.
If you want loud cross extraction, just put on a dual tip muffler. |
john rogers |
Jul 7 2006, 09:06 AM
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#15
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Senior Member Group: Members Posts: 1,525 Joined: 4-March 03 From: Chula Vista CA Member No.: 391 |
I run stingers on my 2L vintage race car and as Steve noted above the jetting has to be fattened up some when switching from a muffler. I have to go from 160 mains to 170 mains on the Weber tripple throats. Above 7K they make a very high pitched sound and I have started to wear ear plugs as my eard ring after a 30 minute race. If the car is dyno'd for the megaphone/stingers then you wull make more power as was shown on my dyno tests with 185HP at the rear wheels with stingers and 172HP with the muffler with dual outlets that makes exactly 92 DB. If you do change the exhaust, invest in some dyno time to get things set right because as Wayne Baker sez "an hour of dyno time is worth at least 4 hours of work at the track". My experience has shown this to be true.
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Joe Bob |
Jul 7 2006, 09:10 AM
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#16
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Retired admin, banned a few times Group: Members Posts: 17,427 Joined: 24-December 02 From: Boulder CO Member No.: 5 Region Association: None |
HUH....WHAT????
I LEFT MY EAR PLUGS AT HOME....I'M NOT SHOUTING...... |
Trekkor |
Jul 7 2006, 10:38 AM
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#17
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
Thanks for the replies.
Another "creation" I've been dreaming about is taking two "Cherry Bomb" glass packs , shortening them to 18" an welding a mounting flange to them for fun. Maybe I'm just bored (IMG:style_emoticons/default/idea.gif) KT |
Van914 |
Jul 7 2006, 12:23 PM
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#18
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Van914 Group: Members Posts: 698 Joined: 5-January 03 From: Cincinnati, Ohio Member No.: 90 Region Association: Upper MidWest |
trekkor,
Why go to all that trouble. Just buy race muflers from Jeg's or Summit. van914 |
Trekkor |
Jul 7 2006, 12:42 PM
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#19
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
I like a project... (IMG:style_emoticons/default/welder.gif) (IMG:style_emoticons/default/smash.gif)
Phase 9's would be nice though. (IMG:style_emoticons/default/idea.gif) KT |
TimT |
Jul 7 2006, 12:58 PM
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#20
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retired Group: Members Posts: 4,033 Joined: 18-February 03 From: Wantagh, NY Member No.: 313 |
here a project,
Pair of Coast mufflers, with a crossover I made. The mufflers are straight through. Plenty loud if thats what your after The systems really shrieks at 7500 RPM Burns stainless makes a similar muffler to the Coast. Both the Coast and Burn mufflers are available witht either glass packing, or stainless wool packing, and are rebuildable. werd up yo Attached image(s) |
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