Compression Ratio Differences
Thread Starter
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Joined: Feb 1999
Posts: 19,659
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From: Lenoir City Tennessee
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Compression Ratio Differences
Metal Wulf brought up the question about the XE262 Comp Cam so I got to looking at CC website for more information on the cam. After doing some looking I found out that the XE262 is there most powerful cam as far as torque is concerned in the XE line. This is on a standard engine rated at 9.25:1 CR. What would a 10:1 ratio do to the HP and Torque numbers? I am wondering about my HP/Torque numbers.
Here is the graph that Comp Cams has.
COMP Cams, Inc.™
Camshaft dyno sheets
Dyno Results
Camshaft Part # 12-238-2 Designation XE262H-10
Duration @ 0.006" 262 / 270 Duration @ 0.050" 218 / 224
Max Lift w/ 1.5RR 462 / .469 Lobe Separation 110
Lobe ID#'s 5442 / 5201 Intake Centerline 106
Engine Type Chevrolet 350 Small Block
Bore 4.040" Stroke 3.480"
Displacement 356 Compression 9.25:1
Heads Dart S/R Intake Edelbrock Performer
Carburetor Holley #3310 Vac. Sec. Exhaust 1 5/8" Headers
Max Torque 415 ft*lbs @ 3700 RPM Max Power 348 HP @ 5300 RPM
Manifold Vacuum 17.5" Hg @ 800 RPM & 18.5" Hg @ 1000 RPM w/ no load.
Here is a link to the page with all the graphs so you can compare all of the XE and HR cams. http://www.compcams.com/information/...ts/DynoSheets/
[Modified by Eddie 96, 8:46 AM 12/16/2002]
Here is the graph that Comp Cams has.
COMP Cams, Inc.™
Camshaft dyno sheets
Dyno Results
Camshaft Part # 12-238-2 Designation XE262H-10
Duration @ 0.006" 262 / 270 Duration @ 0.050" 218 / 224
Max Lift w/ 1.5RR 462 / .469 Lobe Separation 110
Lobe ID#'s 5442 / 5201 Intake Centerline 106
Engine Type Chevrolet 350 Small Block
Bore 4.040" Stroke 3.480"
Displacement 356 Compression 9.25:1
Heads Dart S/R Intake Edelbrock Performer
Carburetor Holley #3310 Vac. Sec. Exhaust 1 5/8" Headers
Max Torque 415 ft*lbs @ 3700 RPM Max Power 348 HP @ 5300 RPM
Manifold Vacuum 17.5" Hg @ 800 RPM & 18.5" Hg @ 1000 RPM w/ no load.
Here is a link to the page with all the graphs so you can compare all of the XE and HR cams. http://www.compcams.com/information/...ts/DynoSheets/
[Modified by Eddie 96, 8:46 AM 12/16/2002]
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Joined: Oct 2001
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From: Kingston Tenn.
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St. Jude Donor '03 & '06
Re: Compression Ratio Differences (Eddie 96)
Eddie,
Thinking about a cam swap already?
Jimmy C.
Thinking about a cam swap already?
Jimmy C.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Re: Compression Ratio Differences (jim482)
No, just wondering where I stand with what I have got. I was just wanting to know what difference CR made in the overall scheme.
Pro
Joined: Jun 2002
Posts: 544
Likes: 0
From: La Jolla California
Re: Compression Ratio Differences (Eddie 96)
The gains in HP/torque would probably be around 15-20 each. Run a simulation in DD2000 w/ your cam and engine specs to get a better idea though.
[Modified by Langadorf, 7:35 AM 12/17/2002]
[Modified by Langadorf, 7:35 AM 12/17/2002]
