Comp Cams XE...HL cam in a 440 with HP-manifolds?
#712365
05/31/10 03:34 PM
05/31/10 03:34 PM
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Joined: Feb 2006
Posts: 79 Germany
JS23U
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Hi, I want to change some parts on the Challenger's 440 engine so it will look more stock. Already have HP-manifolds and a stock iron intake lying around. Need help on choosing the right cam. 440 0.030 over 9.7:1 CR (measured) 2500-2800 stall converter 3.23 gears want a hydr cam which gives streetable power from around 2000 to 5500 As I currently have a 20years old design solid cam I already have Isky 1.5:1 rockers. Carb is a Holley 800DP which may stay if it works. Heads are MP Stage 5 iron from the late 80s. Ported with 2.14 and 1.81 valves. 2.5" exhaust system, TTI, still to be bought Basically my goal is a stock looking engine with HP-manifolds that can perform a bit better than stock. Don't want a F.A.S.T. car, no extrude hone or such. Want to run the stock dual snorkel air cleaner. Intake might be changed to aftermarket dual plane if it helps. I read about the Comp cams XE275HL. Will that cam be too much for stock intake and exhaust? Should I rather go with standard lift? Whats the rpm where the HP manifolds will considerably cut power off? Thanks Jens
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: JS23U]
#712372
06/01/10 03:14 AM
06/01/10 03:14 AM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
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I would have one of the professionals recommend a custom ground cam. I am guessing something with a wider LSA, and maybe extra exhaust duration if you are running stock exhaust manifolds. Just look at the unusual specs of the stock 440 HP cam: 268/284 duration, 115 LSA, installed at 113 intake CL. Timing Events: IO=21 IC=67 EO=79 EC=25 Overlap=46 This profile allows the exhaust to open really early to reduce pumping losses, while minimizing overlap that could cause reversion into the intake to get that smooth idle quality. The XE275HL cam is a good cam (nice fast lobe profile), but really is setup more for use with headers. This cam is 275/287 duration, 110 LSA installed at 106 degrees: cam timing: IO=31.5 IC=63.5 EO=77.5 EC=29.5 Overlap=61 Looking at the timing specs, the stock cam actually opens the exhaust valve sooner that the comp cam does, and the comp cam (with more duration) closes the intake valve sooner than the stock valve, so most of the extra duration is in the overlap period of 61 degrees vs. 46 degrees. my (about what its worth), might be ordering the XE275HL cam on a 112 or 113 LSA, and install it at about 108-110 degrees? Example of the XE275HL cam with 112 and 113 LSA installed at 108 and 110 intake CL.: Duration is still 275/287 112/108 ----- 113/110 IO=29.5 ----- IO=27.5 IC=65.5 ----- IO=67.5 EO=79.5 ----- EO=79.5 EC=27.5 ----- EC=27.5 Overlap=57 -- 55 I like the look of the 112/108?
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: mike s]
#712373
06/01/10 03:17 AM
06/01/10 03:17 AM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
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If you decide to go with the RPM manifold, you may want to check your hood clearance, just for good measure.
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: 451Mopar]
#712375
06/01/10 03:26 AM
06/01/10 03:26 AM
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Joined: Nov 2009
Posts: 2,275 Desert Tracker
HYPER8oSoNic
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Quote:
I would have one of the professionals recommend a custom ground cam. I am guessing something with a wider LSA, and maybe extra exhaust duration if you are running stock exhaust manifolds. Just look at the unusual specs of the stock 440 HP cam: 268/284 duration, 115 LSA, installed at 113 intake CL. Timing Events: IO=21 IC=67 EO=79 EC=25 Overlap=46
This profile allows the exhaust to open really early to reduce pumping losses, while minimizing overlap that could cause reversion into the intake to get that smooth idle quality.
The XE275HL cam is a good cam (nice fast lobe profile), but really is setup more for use with headers. This cam is 275/287 duration, 110 LSA installed at 106 degrees: cam timing: IO=31.5 IC=63.5 EO=77.5 EC=29.5 Overlap=61
Looking at the timing specs, the stock cam actually opens the exhaust valve sooner that the comp cam does, and the comp cam (with more duration) closes the intake valve sooner than the stock valve, so most of the extra duration is in the overlap period of 61 degrees vs. 46 degrees.
my (about what its worth), might be ordering the XE275HL cam on a 112 or 113 LSA, and install it at about 108-110 degrees? Example of the XE275HL cam with 112 and 113 LSA installed at 108 and 110 intake CL.: Duration is still 275/287 112/108 ----- 113/110 IO=29.5 ----- IO=27.5 IC=65.5 ----- IO=67.5 EO=79.5 ----- EO=79.5 EC=27.5 ----- EC=27.5 Overlap=57 -- 55
I like the look of the 112/108?
Makes sense to me!!! That 112-110 range of centerline and lower overlap, can really compliment a good dual plane manifold. Better response and wider powerband.
"Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: HYPER8oSoNic]
#712376
06/01/10 08:55 AM
06/01/10 08:55 AM
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Joined: Mar 2005
Posts: 1,630 North Central Florida
eightlitermopar
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I really like this thread as it is almost identical to the 440 I am currently working on. HIJACK--I have never ordered a cam with a wider LSA, so.....does one just call comp and tell them they want a custom grind? Tell us how this motor turns out! I am really interested! eight
Mopar or no car
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: JS23U]
#712377
06/01/10 09:08 AM
06/01/10 09:08 AM
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Joined: Oct 2007
Posts: 736 New York
R/T1968R/T
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Im running the XE275Hl with exhaust manifolds. Nice cam with good power. I had to use adjustable rockers because the ramps were very aggressive. According to Andyf keep duration lower than 245 at.050 because the torque curve will fall out of bed with the manifolds!!!Take a look at his articles. http://www.compcams.com/Community/Articles/Details.asp?ID=2004264609
Last edited by R/T1968R/T; 06/01/10 09:23 AM.
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: JS23U]
#712379
06/01/10 03:54 PM
06/01/10 03:54 PM
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Joined: Jun 2006
Posts: 5,166 CT
GTX MATT
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I think you'd be best off with a custom grind so you can keep the LSA at 114 to run with the manifolds.
Now I need to pin those needles, got to feel that heat Hear my motor screamin while I'm tearin up the street
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: R/T1968R/T]
#712380
06/02/10 12:07 AM
06/02/10 12:07 AM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
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I like Andys article. The Mopar 0.529" cam (#4120659) has duration of 284/284 112 LSA. If it was installed at 106 degrees the timing events look like this: IO=36 IC=68 EO=80 EC=24 Overlap = 60
Looking at the cam specs, specifically the Intake Closing point, I suspected that Andys engine in the article had decent compression. Making a few guesses to fill in the blanks, like piston dish volume, and gead gasket volume, I calculated Andys engine had about 10.75:1 compression? and had a cranking gauge pressure of about 160 psi? I can see where using a larger intake duration or installing the cam in a more retarded position would really delay the intake valve closing point and reduce the cylinder pressure, resulting in the loss of low end torque.
Anyhow, I am not recommending a specific cam. I just think it is an interesting exercise to compare different cams, and show how changes in LSA and installed CL change the valve timing events and overlap.
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Re: Comp Cams XE...HL cam in a 440 with HP-manifolds?
[Re: AndyF]
#712383
06/03/10 08:34 PM
06/03/10 08:34 PM
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Joined: May 2008
Posts: 5,399 Aurora, Colorado
451Mopar
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Quote:
This article has more cam testing that I did with that engine.
http://www.compcams.com/Community/Articles/Details.asp?ID=-1849542054
(all of these articles are in the tech archives on this board)
Good article Andy. What are the piston specs, head volume and gasket volume? The article says 10.2:1 compression, but I though the first article mentions a zero deck height flat top piston? My assumptions were: Bore=4.375" Stroke=3.875" Rod Length=6.760" Block Deck height=9.980" Piston compression distance=1.283" (zero deck?) Piston valve reliefs=4cc ? Felpro 1009 head gasket (4.410" bore, 0.039" thick, 9.9cc volume) Cylinder head chamber volume = 84cc (as advertised by Edelbrock?)
Anyhow, with the above I calculated 10.76:1 compression? What specs, or combination of changes resulted in the lower compression ratio?
Just curious, because I am trying to figure out a cam for my 4.25" stroker 440 (505") that I may run manifolds on. I have been looking at using a hydraulic roller because the engine may sit for months at a time between being driven, and I fear wiping out another flat tappet cam. I have been considering the Comp highlift magnum profile #3122 (290/236/160,@0.006/0.050/0.200"), 0.608" lift @ 1.6:1 ratio for the intake (looks pretty agressive with 160@0.200"?) I havent decided on the Exhaust lobe yet, I just started on this awhile ago.
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