[k.pascoe]

Finally got my engine and car ready for the track. It's a 552 ci A441 hemi/boss.
I've started it a few times, ran threw a 10 gallons of X16. Finally got the rings seated.
It is just the most obnoxious loud, bad ass sounding engine I've ever built.
My question. It seems like in the big hp n/a world the engines seem to be quiet at idle.
Would that be in the header design? Camshaft?

Thanks for any comments

 

[BBF612]

low velocity when the exhaust valve opens

Love the car and engine, good luck.

 

[k.pascoe]

low velocity when the exhaust valve opens

Love the car and engine, good luck.

Thank you.
I know sounds like a really dumb question.

 

[BBF612]

Not really a dumb question, as it could be the camshaft/reversion also along with the low velocity of the exhaust, to make it breath on the top end you have to give something up on the bottom end.

 

[Ed Curtis]

I remember the Hot Street engine used to have some kind of rhythmic "whistle" at idle when it was on point...

 

[Mummert]

Loud usually means wasted heat energy, early exhaust valve opening, poor combustion efficiency. Best running engines I've been around are quiet with open headers.

 

[18degsbcregal]

You can’t make a post about how awesome the car sounds and not post a video of it 😉

 

[BLUEOVALRACER]

You can’t make a post about how awesome the car sounds and not post a video of it 😉

X2!!

 

[Half Breed]

I think it has to do with the camshaft profile. The larger camshafts bleed off cylinder pressure at low RPM.

 

[k.pascoe]

Loud usually means wasted heat energy, early exhaust valve opening, poor combustion efficiency. Best running engines I've been around are quiet with open headers.

I agree

 

[carnutbill67]

I remember the Hot Street engine used to have some kind of rhythmic "whistle" at idle when it was on point...

Man I loved Hot Street. What class is similar today? Screaming rpm just does it for me.

 

[Ed Curtis]

Man I loved Hot Street. What class is similar today? Screaming rpm just does it for me.

NMCA NA-10.5 class is about the closest... mixed brands, all motor!

One of my favorite of these class cars!

 

[la360]

A la360 engine I have was very loud on the dyno, had an over the top Howards flat tappet camshaft in it. Never really knew why, but we built it out of parts we had lying around. Made decent power for what it was.

 

[mrdragster1970]

.

I was told my 850-900 HP no box car is louder than my 1200 HP T/S car???


.

 

[600" BBF]

Does dB = HP ?





Depends on how much CH3NO2 is in the mix.

 

[BigRich71]

It all depends on the application. . I have heard super stock engines that sounded like a chain of dynamite at idle and have heard 700 inch mountain motors that had a quiet "wet" or "chirpy" sounding idle. Back when we were kids we always wanted that low "chirpy" idle for our street/strip cars. My guess is that the same cam timing that is used to crutch up the limited port flow and limited compression of the super stocker probably cause the crackling sound. On the opposite end of the scale would be a well refined engine with purpose built ports and tight wedge type combustion chambers that can run the kind of exhaust lobe timing that works with the good cylinder blow down that such an engine offers.

 

[k.pascoe]

It all depends on the application. . I have heard super stock engines that sounded like a chain of dynamite at idle and have heard 700 inch mountain motors that had a quiet "wet" or "chirpy" sounding idle. Back when we were kids we always wanted that low "chirpy" idle for our street/strip cars. My guess is that the same cam timing that is used to crutch up the limited port flow and limited compression of the super stocker probably cause the crackling sound. On the opposite end of the scale would be a well refined engine with purpose built ports and tight wedge type combustion chambers that can run the kind of exhaust lobe timing that works with the good cylinder blow down that such an engine offers.

Maybe something to do with the hemi chamber. A SS/AH Chrysler hemi's are pretty angry sounding at idle.

 

[BigRich71]

No,this was a wedge headed single 4 barrel engine. A 63 or 64 Plymouth.

 

[dfarr67]

Does dB = HP ?
People around seem to think so on their street vehicles. Annoying.

 

[AlexLTDLX]

From a pure science perspective, no. It takes energy to generate sound. If you can use that energy to generate rotational force instead, then you're more efficient. I was just thinking about this - my Whipple screamed like a velociraptor. But it also took 120hp to drive it. The current forced induction is dead silent and only takes 47hp to drive it to make the same power.

Then again, the Whipple sounded mean. So, you know, choose your poison. And, like others posted, I would like to hear that car too - that Poncho that Ed posted is pretty bad ass.