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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: BSB67]
#1727959
01/16/15 12:44 AM
01/16/15 12:44 AM
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Joined: Jan 2003
Posts: 6,591
Canton, Ohio
Sport440
master
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master
Joined: Jan 2003
Posts: 6,591
Canton, Ohio
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Quote:
Quote:
We can get really in depth with this if you like......but for now we'll just keep it basic.......
Just before the piston reaches BDC, the intake valve should close (tightly) thus getting the max cylinder volume of charge.....
Really?
Yep, totally wrong. Not even close. 
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: Sport440]
#1727960
01/16/15 12:59 AM
01/16/15 12:59 AM
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Joined: Nov 2007
Posts: 21,831
Kirkland, Washington
Pacnorthcuda
Too Many Posts
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Too Many Posts
Joined: Nov 2007
Posts: 21,831
Kirkland, Washington
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Quote:
Quote:
Quote:
We can get really in depth with this if you like......but for now we'll just keep it basic.......
Just before the piston reaches BDC, the intake valve should close (tightly) thus getting the max cylinder volume of charge.....
Really?
Yep, totally wrong. Not even close.
Maybe in a Briggs & Stratton...... Maybe...nah, not even then.
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: BradH]
#1727962
01/16/15 03:14 AM
01/16/15 03:14 AM
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Joined: Jan 2005
Posts: 1,260
Las Vegas NV
moparmanjames
pro stock
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pro stock
Joined: Jan 2005
Posts: 1,260
Las Vegas NV
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Quote:
Quote:
Quote:
Quote:
Head flow is king, period. If you've got a good set of heads you will make power.
It's not that simple...
Not that simple but it's a damn good start.
Only if other key things are taken into account. Just because you've got a "good set of heads" that flow well doesn't mean they're the right set of heads for an application.
Put a set of 350cc ported Indy 440-1s on a stock-stroke 400 and you'll have a gutless pig below about 5500 and needs to rev to 8000 to even come close to making the heads "work". Not my idea of a good combination...
I'll take an "OK" set of heads for the right application over a "good set" of heads for the wrong one.
(And this is what results when some people make really generic - and flawed - statements that more detail-specific people take exception to.  )
You make a valid point but really, it's kind of an excessive example.
A better comparison that got me thinking a few years back was when I think it was Car Craft or whatever magazine built a small block chevy 400 and a big block chevy 400 both with decent heads and a hydraulic cam and ran them in a 70 something Chevelle.
Even though the Big Block weighed over 200lbs more it beat the small block every time by like 3 tenths, they both ran in the 12's.
Now this isn't the end all be all of the argument but it did show that at least for that combination the bigger port head in a heavy car with small cubes won the battle.
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: LaRoy Engines]
#1727963
01/16/15 03:33 AM
01/16/15 03:33 AM
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Joined: Feb 2004
Posts: 4,501
Gainesville,FL
goldmember
master
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master
Joined: Feb 2004
Posts: 4,501
Gainesville,FL
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Quote:
It's not a small block. Does have what I think are bigger than average heads and a smaller cam. We were doing some factory iron head tests and had the Indy EZ heads in the shelf.
440 .030 over, old TRW 6-pack pistons w/ stock rods, 10.5:1 compression, EZ Max Wedge heads flowing 360 cfm @ .700", Edelbrock Victor intake, 850 Mighty Demon carburetor, XE285HL camshaft 241/247 @ .050, .545/.545, 1.6 rockers.
Start dyno pull at 3,500rpm. 500 lb-ft from 3,500-6,000 rpm. Peak torque 543 @ 5,200 rpm and peak HP of 595 @ 6,400 rpm. Don't know if that's good or bad, just is what it is. Never pulled it lower in the rpm range with this combination so can't speak on that.
So your posted combo uses approx 262 cfm from those heads? That's the kind of combo that would be a bummer to me. Heads that are capable of real output on a street hp build. We have a NSS car 3730lbs 452 cid that makes 650hp with much weaker heads,pump gas,small roller cam,crappy intake,etc and I am pissed that it's such a turd. Match the parts and good things happen. I'm not knocking you as I'm sure you see limiting parts to that build.
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: goldmember]
#1727964
01/16/15 03:47 AM
01/16/15 03:47 AM
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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Quote:
We have a NSS car 3730lbs 452 cid that makes 650hp with much weaker heads,pump gas,small roller cam,crappy intake,etc and I am pissed that it's such a turd.
So, what does the turd run?
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: goldmember]
#1727966
01/16/15 04:49 AM
01/16/15 04:49 AM
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Joined: Dec 2014
Posts: 100
KS
Cogito
member
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member
Joined: Dec 2014
Posts: 100
KS
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Quote:
Quote:
It's not a small block. Does have what I think are bigger than average heads and a smaller cam. We were doing some factory iron head tests and had the Indy EZ heads in the shelf.
440 .030 over, old TRW 6-pack pistons w/ stock rods, 10.5:1 compression, EZ Max Wedge heads flowing 360 cfm @ .700", Edelbrock Victor intake, 850 Mighty Demon carburetor, XE285HL camshaft 241/247 @ .050, .545/.545, 1.6 rockers.
Start dyno pull at 3,500rpm. 500 lb-ft from 3,500-6,000 rpm. Peak torque 543 @ 5,200 rpm and peak HP of 595 @ 6,400 rpm. Don't know if that's good or bad, just is what it is. Never pulled it lower in the rpm range with this combination so can't speak on that.
So your posted combo uses approx 262 cfm from those heads? That's the kind of combo that would be a bummer to me. Heads that are capable of real output on a street hp build. We have a NSS car 3730lbs 452 cid that makes 650hp with much weaker heads,pump gas,small roller cam,crappy intake,etc and I am pissed that it's such a turd. Match the parts and good things happen. I'm not knocking you as I'm sure you see limiting parts to that build.
Can you provide specifics of the engine? Too vague to use as a datapoint...
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: Cogito]
#1727967
01/16/15 05:19 AM
01/16/15 05:19 AM
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Joined: Feb 2004
Posts: 4,501
Gainesville,FL
goldmember
master
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master
Joined: Feb 2004
Posts: 4,501
Gainesville,FL
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Quote:
Quote:
Quote:
It's not a small block. Does have what I think are bigger than average heads and a smaller cam. We were doing some factory iron head tests and had the Indy EZ heads in the shelf.
440 .030 over, old TRW 6-pack pistons w/ stock rods, 10.5:1 compression, EZ Max Wedge heads flowing 360 cfm @ .700", Edelbrock Victor intake, 850 Mighty Demon carburetor, XE285HL camshaft 241/247 @ .050, .545/.545, 1.6 rockers.
Start dyno pull at 3,500rpm. 500 lb-ft from 3,500-6,000 rpm. Peak torque 543 @ 5,200 rpm and peak HP of 595 @ 6,400 rpm. Don't know if that's good or bad, just is what it is. Never pulled it lower in the rpm range with this combination so can't speak on that.
So your posted combo uses approx 262 cfm from those heads? That's the kind of combo that would be a bummer to me. Heads that are capable of real output on a street hp build. We have a NSS car 3730lbs 452 cid that makes 650hp with much weaker heads,pump gas,small roller cam,crappy intake,etc and I am pissed that it's such a turd. Match the parts and good things happen. I'm not knocking you as I'm sure you see limiting parts to that build.
Can you provide specifics of the engine? Too vague to use as a datapoint...
452" Victor heads, bowl blend,VJ and guides corrected,10.8to1 comp, mid 250's/.640gross 108lsa 105 ICL,Indy modman intake(yuck), 2 edelbrock 600 carbs(MORE YUCK),2" hooker headers. It's getting more comp and cam as we type. The other restrictions will stay as they are not for me to change. 
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: goldmember]
#1727968
01/16/15 09:26 AM
01/16/15 09:26 AM
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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Quote:
It runs 130-132mph. 65 B body with a roll bar and 240lb driver.
3730#s w/ the 240# driver, or plus the 240# driver?
Is the 650 HP reference from engine dyno data, or estimated from on-track performance?
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: goldmember]
#1727969
01/16/15 12:17 PM
01/16/15 12:17 PM
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Joined: Oct 2011
Posts: 559
Idaho
LaRoy Engines
mopar
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mopar
Joined: Oct 2011
Posts: 559
Idaho
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Quote:
Quote:
It's not a small block. Does have what I think are bigger than average heads and a smaller cam. We were doing some factory iron head tests and had the Indy EZ heads in the shelf.
440 .030 over, old TRW 6-pack pistons w/ stock rods, 10.5:1 compression, EZ Max Wedge heads flowing 360 cfm @ .700", Edelbrock Victor intake, 850 Mighty Demon carburetor, XE285HL camshaft 241/247 @ .050, .545/.545, 1.6 rockers.
Start dyno pull at 3,500rpm. 500 lb-ft from 3,500-6,000 rpm. Peak torque 543 @ 5,200 rpm and peak HP of 595 @ 6,400 rpm. Don't know if that's good or bad, just is what it is. Never pulled it lower in the rpm range with this combination so can't speak on that.
So your posted combo uses approx 262 cfm from those heads? That's the kind of combo that would be a bummer to me. Heads that are capable of real output on a street hp build. We have a NSS car 3730lbs 452 cid that makes 650hp with much weaker heads,pump gas,small roller cam,crappy intake,etc and I am pissed that it's such a turd. Match the parts and good things happen. I'm not knocking you as I'm sure you see limiting parts to that build.
Sure, I see. Was just attempting to show from my experience a big head/small cam build. The 451 build with the Edelbrock RPM heads pulled the same 500 lb-ft @ 3500 rpm but was still carrying 565 lb-ft @ 7200 rpm. Like you say, just a better match to the parts.
Last edited by LaRoy Engines; 01/16/15 12:19 PM.
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: Clanton]
#1727971
01/20/15 04:25 AM
01/20/15 04:25 AM
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Joined: Apr 2008
Posts: 373
sandwich IL
sublimehemi
enthusiast
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enthusiast
Joined: Apr 2008
Posts: 373
sandwich IL
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just wanted to post my recent build...
528 hemi all alum
out of box regular non victor edelbrock/mopar hemi heads
out of box mopar/barton 4150 single plane
right around 10.1 compression
super tiny duration efi rich nebel book hemi camshaft advanced 4 degrees
comp elite super lightweigt mechanical roller lifters
barton roller rockers with pushrod oiling
made 670 hp at 6200 and 660 tq at 4200 not a happy dyno either very hard to make hp on this dyno
we all were very impressed....my engine builder mike and dale chenoweth said good luck on even getting 600 hp...he and his dad built many hemis...one thing for sure is it did not like anything past 30 deg total and hp drop is very quick after 6200...but all in all i am so happy cause i have a motor that idles like a baby and pulls excellent vacuum 13-14...operates well with little 3200-3400 tight stall and baby 3.54 gears...
70 charger ,all aluminum 528 hemi 727 cope rmvb,680hp 670 tq,full sequential holley hp efi,full hotchkis tvs,qa1 k and lowers,borgeson steering box cass viper 11.75 with cass s-trac dana 3.54
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: sublimehemi]
#1727972
01/20/15 04:26 AM
01/20/15 04:26 AM
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Joined: Apr 2008
Posts: 373
sandwich IL
sublimehemi
enthusiast
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enthusiast
Joined: Apr 2008
Posts: 373
sandwich IL
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pic of hemi....i actually dropped a .05 degree of duration off cam so it was ordered as 241 249...but the size of the elite lifter wheel diameter probably increased it by .03? anyways i could of put a set victor jr hemi heads and 270 280 duration and had 110 or 108 lsa but bigger stall and bigger gears and would have been needed and low end tq would of suffered but it probably would have done 750 hp at 6700 6800?but then idle would be rough and no vacuum...be careful on your camshaft selection!!
Last edited by sublimehemi; 01/20/15 04:45 AM.
70 charger ,all aluminum 528 hemi 727 cope rmvb,680hp 670 tq,full sequential holley hp efi,full hotchkis tvs,qa1 k and lowers,borgeson steering box cass viper 11.75 with cass s-trac dana 3.54
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Re: Big Ports, Big Flow #s, And Low Duration Camshafts
[Re: Clanton]
#1727974
01/20/15 05:05 PM
01/20/15 05:05 PM
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Joined: Apr 2008
Posts: 373
sandwich IL
sublimehemi
enthusiast
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enthusiast
Joined: Apr 2008
Posts: 373
sandwich IL
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i think 330-340 and victor jr are 380...no psi data... im happy i went with this combo.....my duration is so puny and my lsa at 114.. so for cam that in it...makes for a great street engine with usable rpm range..
70 charger ,all aluminum 528 hemi 727 cope rmvb,680hp 670 tq,full sequential holley hp efi,full hotchkis tvs,qa1 k and lowers,borgeson steering box cass viper 11.75 with cass s-trac dana 3.54
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