Camshaft / Exhaust Combo
#1301721
09/10/12 08:53 PM
09/10/12 08:53 PM
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Joined: Feb 2009
Posts: 583
San Antonio, TX
CurYellowBird
OP
mopar
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OP
mopar
Joined: Feb 2009
Posts: 583
San Antonio, TX
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Currently finishing up my 440 build. I want to reuse my factory hi-po manifolds from my roadrunner.
The two cams I'm looking at are the Lunati 60303 and 60304.
I've read on other posts here that guys ran the 60303 in low compression 440's but had headers. I want to run the 60304 since my 440 short block is running six pack pistons and higher compression.
Can I run the larger cam with hipo-manifolds and a 3 inch exhaust or is it not a good idea?
Project War Bird:
1971 Plymouth Roadrunner
383 4 speed with air conditioning
GY3 Curious yellow
All original
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Re: Camshaft / Exhaust Combo
[Re: Pacnorthcuda]
#1301724
09/10/12 10:09 PM
09/10/12 10:09 PM
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Joined: Feb 2009
Posts: 583
San Antonio, TX
CurYellowBird
OP
mopar
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OP
mopar
Joined: Feb 2009
Posts: 583
San Antonio, TX
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The heads are 452's from Aero Head that have 2.14/1.81 valves. The heads were surfaced so probably close to stock cc. The short block is close to zero deck after going with L2355 flat tops.
Please define drone for me because I don't really know the term.
Project War Bird:
1971 Plymouth Roadrunner
383 4 speed with air conditioning
GY3 Curious yellow
All original
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Re: Camshaft / Exhaust Combo
[Re: CurYellowBird]
#1301725
09/10/12 10:12 PM
09/10/12 10:12 PM
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Joined: Nov 2007
Posts: 21,825
Kirkland, Washington
Pacnorthcuda
Too Many Posts
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Too Many Posts
Joined: Nov 2007
Posts: 21,825
Kirkland, Washington
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Quote:
The heads are 452's from Aero Head that have 2.14/1.81 valves. The heads were surfaced so probably close to stock cc. The short block is close to zero deck after going with L2355 flat tops.
Please define drone for me because I don't really know the term.
Its a resonance (think BUZZING) in the exhaust while your cruising at light-mid throttle. Often in the 40-60mph range.
Noise to the point of NO conversation in the car. VERY annoying.
3" pipes often contribute to it, and in my opinion 3" pipes connected to manifolds ASK for it.
My experience was brutal. Previous owner installed a 500W stereo to drown it out!!!
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Re: Camshaft / Exhaust Combo
[Re: BSB67]
#1301728
09/10/12 10:30 PM
09/10/12 10:30 PM
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Joined: Feb 2009
Posts: 583
San Antonio, TX
CurYellowBird
OP
mopar
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OP
mopar
Joined: Feb 2009
Posts: 583
San Antonio, TX
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This is a 4 speed car with manual brakes.
With the piston at TDC, the ridge is barely enough for me to catch with a fingernail. I am not at my dad's so I can't give exact measurement. I'm using Felpro replacement head gaskets to try and keep the compression somewhat down rather than using steel shim gaskets.
Now I know what drone is. I've heard it before just never knew there was a name to it.
Project War Bird:
1971 Plymouth Roadrunner
383 4 speed with air conditioning
GY3 Curious yellow
All original
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Re: Camshaft / Exhaust Combo
[Re: BSB67]
#1301729
09/11/12 12:11 AM
09/11/12 12:11 AM
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Joined: Apr 2008
Posts: 1,285
Pacific NW USA
CompSyn
pro stock
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pro stock
Joined: Apr 2008
Posts: 1,285
Pacific NW USA
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Quote:
If you want a larger cam try Mr Six Pac or Dwyane Porter.
I believe the distinction has been drawn that a Big Block Mopar with exhaust manifolds benefits from a cam center line somewhere around 112-to-114 and exhaust duration not much more than 284.
Andy Finkbeiner's dyno testing seems to confirm this as well as the track tuned Mr. 6Pack cam from Bob Karkashian.
So there again, the Mr. 6pack grind I decided to go with is optimized to run with bone stock 906 heads and HP manifolds. It's center line is 114 and has exhaust duration somewhere in the ballpark of the stock Magnum/Road Runner cam ~ 284.
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