Exhaust whistle
09-04-2007, 12:08 PM
#1
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JOURNEYMAN
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Location: Letellier MB, Canada
Posts: 31
Exhaust whistle
I was in Brainerd at the national event and noticed a lot of the cars had a whistle at idle. Almost sounded like an old VW bug. Just yesterday my buddy fired up his 598 for me and the wistle was really loud at idle. Has anyone els noticed this? If so, do you know the cause? :?:
09-05-2007, 04:53 AM
#3
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JOURNEYMAN
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Location: Letellier MB, Canada
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My buddies 598 is a 10.5-1 motor that runs on pump gas. I'm not sure if compression is the cause. One of the theory's he had is its the D shaped exhaust ports creating a negative pressure or something at the header as the exhaust flow exits the head and enters the header. Personaly I don't care for the whistling sound, and would like to avoid it when I build my headers.
09-05-2007, 10:41 AM
#4
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I started a very long thread about this on SpeedTalk.; Many different of the top engine and cylinder head professionals in the industry chimmed in about this subject. People heavily involved in Pro Stock racing posted.
Bottom line is that no one really knows.
10 identical pro stock engines. all engines had equal power to within a few hundreths of a second with each other in the same car. 5 identical sets of headers. Engines that had the Chirp/Whistle/TGweety Bird, Lost it by changing headers. Engines receiving the headers that were Chirping on other engines that did not chirp before still did not chirp when receiving the headeres that chirped on the chirping engines. Engines that chirped quite chirping with head chenaces.
Brad and David Morgan and their creww spent much time in R&D just to pin point what was causing the strange sounds. Notta!. No conclusions.
So I guess we will all keep guessing indefinetly.
Ed
Bottom line is that no one really knows.
10 identical pro stock engines. all engines had equal power to within a few hundreths of a second with each other in the same car. 5 identical sets of headers. Engines that had the Chirp/Whistle/TGweety Bird, Lost it by changing headers. Engines receiving the headers that were Chirping on other engines that did not chirp before still did not chirp when receiving the headeres that chirped on the chirping engines. Engines that chirped quite chirping with head chenaces.
Brad and David Morgan and their creww spent much time in R&D just to pin point what was causing the strange sounds. Notta!. No conclusions.
So I guess we will all keep guessing indefinetly.
Ed
09-05-2007, 12:03 PM
#6
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JOURNEYMAN
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Join Date: May 2004
Location: Letellier MB, Canada
Posts: 31
Originally Posted by edvancedengines
I started a very long thread about this on SpeedTalk.; Many different of the top engine and cylinder head professionals in the industry chimmed in about this subject. People heavily involved in Pro Stock racing posted.
Bottom line is that no one really knows.
10 identical pro stock engines. all engines had equal power to within a few hundreths of a second with each other in the same car. 5 identical sets of headers. Engines that had the Chirp/Whistle/TGweety Bird, Lost it by changing headers. Engines receiving the headers that were Chirping on other engines that did not chirp before still did not chirp when receiving the headeres that chirped on the chirping engines. Engines that chirped quite chirping with head chenaces.
Brad and David Morgan and their creww spent much time in R&D just to pin point what was causing the strange sounds. Notta!. No conclusions.
So I guess we will all keep guessing indefinetly.
Bottom line is that no one really knows.
10 identical pro stock engines. all engines had equal power to within a few hundreths of a second with each other in the same car. 5 identical sets of headers. Engines that had the Chirp/Whistle/TGweety Bird, Lost it by changing headers. Engines receiving the headers that were Chirping on other engines that did not chirp before still did not chirp when receiving the headeres that chirped on the chirping engines. Engines that chirped quite chirping with head chenaces.
Brad and David Morgan and their creww spent much time in R&D just to pin point what was causing the strange sounds. Notta!. No conclusions.
So I guess we will all keep guessing indefinetly.
09-06-2007, 04:22 PM
#7
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Posts: 122
Alot ofthe big cubic inch BBC engines here where I race justy about all have the chirping noise,and they are all big cubic inch motors,I personally like the sound,But it will never be better than the surging of my blown Small Block,and the awesome loud ear piercing burnouts from a blown alcohol motor
