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08-10-04, 01:20 PM
| | Official Member | | Join Date: April 2003 Location: Austin, TX
Posts: 376
| | | Help with camshaft recommendations.
These are the camshaft specifications that both Comp Cams and Cam Research gave me for the engine combo listed below. Remember the car is for the street, maybe sometimes strip, and needs enough vacuum for power disk brakes. My max street RPM will be around 6000. Both will idle around 750 - 800 RPM. I am trying to reach my goal of about 480 - 500 HP. What do you guys think?
#1 Comp Cams = Hydraulic Roller Camshaft (duration @ .050" = 232/240 ; valve lift w/ 1.6 = 565/574, Valve Overlap = 65 deg, Lobe Sep = 110 deg w/ 4 deg advance, 12" Vacuum, Operating Range = 2200 - 6200 RPM (Small Base Circle Cam)
#2 Comp Cams = Hydraulic Roller Camshaft (duration @ .050" = 224/232 ; valve lift w/ 1.6 = 555/565, Valve Overlap = 57 deg, Lobe Sep = 110 deg w/ 4 deg advance, 14 -15" Vacuum, Operating Range = 1800 - 5800 RPM (Small Base Circle Cam)
#3 Cam Research = Hydraulic Roller Camshaft (duration @ .050" = 230/235 ; valve lift w/ 1.6 = 556/556, Valve Overlap = 14 deg, Lobe Sep = 110 deg, 15" Vacuum, Operating Range = 2200 - 4500 RPM (Standard Base Circle Cam)
393w Stroker bored .030" over
Scat Crankshaft 3.850 stroke
Scat H-Beam Rods 6.200 length
AFR 185 Cylinder Heads w/ upgraded springs
Weiand Stealth Intake Manifold
Street Demon 750 CFM Carburetor w/ mechanical secondaries
Comp Cams 1.6 ratio Pro Magnum Roller Rocker Arms
10.0:1 Compression Ratio w/ Forged Probe Pistons
1 3/4" Headers
MSD Ignition
Edelbrock Water Pump
T-5 G-Force Tranny
9" Rearend w/ 3.89 gears and locker | 
08-10-04, 03:14 PM
| | Founding Member | | Join Date: September 2000 Location: south louisiana
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If it's any help, I ran a Ford B303 roller in a 30 over 302, with Canfield Heads. It had plenty of vacuum for the brakes. Lift and duration was .510 and 224 @ .050 The Canfields are the equivalent of your 185's. So , Yes I assume those cams should give you what you want with 90 more cubes than I had. If you can't afford the roller cam route, a slightly milder flat tappet cam would also work. | 
08-10-04, 04:33 PM
| | Founding Member | | Join Date: September 1999 Location: Metro Detroit
Posts: 1,128
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I think any of the cams would work very well. Personally, I like the spec’s on the Cam Research cam, I think that will hit your sweet spot. It should give you good power with being very streetable. 14”-15” of vacuum is a lot. However, I think the operating range you listed for the Cam research cam is a little low – 2000 – 4500? I’d think it would be closer to 2000 to 5800. I vote for Cam research. | 
08-10-04, 05:18 PM
|  | Keeper Of Automotive Oddities | | Join Date: August 1999 Location: Live in GA, But could be any where really.
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08-10-04, 09:17 PM
| | Founding Member | | Join Date: September 2000 Location: south louisiana
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I think that with the shorter valve overlap, the Cam Research grind may be hard to run on pump gas though with a 10.0 to 1 comp ratio. Would be great on a lower comp motor though. | 
08-10-04, 10:27 PM
|  | Founding Member | | Join Date: April 2002 Location: Pensacola FL
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I like #2.
Just right for your cubes IMO. | 
08-10-04, 10:46 PM
|  | Official Member | | Join Date: September 2003 Location: Middle Tn.
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The overlap #s don't jive. Overlap on 3 should be somewhere between 1 & 2. You have some really nice parts. Why not get a custom cam from fti? This is not the time to save money. My next cam will come from Ed Curtis (FTI) or possibly Jay Allen (Camshaft Innovations). | 
08-11-04, 12:28 AM
|  | Founding Member | | Join Date: November 1998 Location: Mesa, AZ
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I'd rather spend a few extra bucks and get an Ed Curtis cam. You'll know you have the RIGHT cam, plus an extra 20 HP  | 
08-11-04, 07:36 PM
| | Official Member | | Join Date: April 2003 Location: Austin, TX
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Ed Curtis? Please give me information on who he works for and his number. What can he do that Comp or Cam Research can't do? | 
08-11-04, 07:46 PM
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08-12-04, 10:45 AM
|  | Official Member | | Join Date: September 2003 Location: Middle Tn.
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| | Quote: |
Originally Posted by wickedmach1 Ed Curtis? Please give me information on who he works for and his number. What can he do that Comp or Cam Research can't do? | Some of the big cam companies have off the shelf customs. If you call them for a recomendation you will possibly get a specialty cam not a custom. People like Ed design a cam from scratch. Stroke, compression, port flow and cross section as well as many other variables determine not only lift and duration, but timing of events as well. Big companies can design great cams, but it seems like smaller companies give more personalized service. | 
08-12-04, 05:04 PM
| | Founding Member | | Join Date: September 2000 Location: south louisiana
Posts: 10,217
| |  How many of y'all have actually run an "off the shelf cam" , then swapped in a custom ground cam into a motor, without doing any other mods other than to accomodate the cam's valvetrain needs ? I mean, NO different pistons, heads, intakes, carbs, etc.? That would be the ONLY way to tell just how good a custom grind is, and how good a value one is over an off the shelf grind.  | 
08-13-04, 11:56 AM
|  | Official Member | | Join Date: September 2003 Location: Middle Tn.
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Originally Posted by D.Hearne  How many of y'all have actually run an "off the shelf cam" , then swapped in a custom ground cam into a motor, without doing any other mods other than to accomodate the cam's valvetrain needs ? I mean, NO different pistons, heads, intakes, carbs, etc.? That would be the ONLY way to tell just how good a custom grind is, and how good a value one is over an off the shelf grind.  | I have never owned a custom cam, but I have never heard someone with a custom cam say it is a waste of money. It is not hard to find a good engine builder that will tell you the importance of the correct timing events. Most tell you it is the last part to buy so that it is right. You might get lucky, but it may cost you 30hp. | 
08-13-04, 07:44 PM
|  | Founding Member | | Join Date: February 2001 Location: Connecticut
Posts: 390
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i think that your #2 coice is the best for what you are trying to accomplish. however i have always been a big fan of crane cams and stronly recommend you check out some of their offerings. i have had really good results with their cams. also something to consider is whether you plan to add a power adder of some sort. you would want a cam with a little more lobe separation. | 
08-13-04, 09:24 PM
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I would think that with a power adder, you'd want a tighter lobe separation, to improve cylinder scavenging and to somewhat reduce the dynamic compression to compensate for the increased compression resulting from supercharging. | 
08-13-04, 09:40 PM
|  | Keeper Of Automotive Oddities | | Join Date: August 1999 Location: Live in GA, But could be any where really.
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Originally Posted by D.Hearne I would think that with a power adder, you'd want a tighter lobe separation, to improve cylinder scavenging and to somewhat reduce the dynamic compression to compensate for the increased compression resulting from supercharging. | And you would be incorrect. | 
08-13-04, 09:45 PM
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08-13-04, 09:54 PM
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I don't know all the why's, but turbo cams usually have more intake lobe and blower cams seem to have more exhaust lobe. Both seem to run 114*-116* lsa. That is to reduce overlap. Blower like more duration and turbos like neastock type. | 
08-13-04, 09:59 PM
|  | Founding Member | | Join Date: February 2001 Location: Connecticut
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D.Hearne the answer can be found at most superchargers websites. i suggest you start with www.procharger.com there is alot of technical info availible there and then check out www.cranecams.com there is so much tech info it will make you insane. seriously | 
08-13-04, 10:01 PM
| | Founding Member | | Join Date: September 2000 Location: south louisiana
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Originally Posted by brianj5600 I don't know all the why's, but turbo cams usually have more intake lobe and blower cams seem to have more exhaust lobe. Both seem to run 114*-116* lsa. That is to reduce overlap. Blower like more duration and turbos like neastock type. | Thanks for the info. Never having run either turbo or superchargers in a gas motor, I didn't know that. But still seems like a little more overlap would be a good thing to improve scavenging even in that situation. | 
08-13-04, 10:17 PM
|  | Keeper Of Automotive Oddities | | Join Date: August 1999 Location: Live in GA, But could be any where really.
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Although none of us, me included, should be making absolutes
Generally for power adders, you want to minimize overlap. Tightening the separation angle increases overlap.
What is "best" depends to a great extent on the type of power adder, supercharger and nitrous cams generally have pretty wide separation angles and a good bit more exhaust duration than intake.
Turbo cams in many cases are single pattern or have more intake than exhaust duration because you have to depend on the exhaust to drive the turbo, so you don't want any reversion or low velocity (at least before the turbine)
Corkey Bell even goes so far as to say the best turbo cam in most cases is the stock cam.
There are of course always exceptions, and there is a great more detail available out there.
HTH | 
08-18-04, 09:30 PM
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just a quick update. the best answer i have for the wider lobe separation came from crane cams website and it basically says. a tight lobe separation tends to build torque early and peaks at a relatively low rpm. a wide lobe separation stretches the torque and power curve out and builds more top end power. and i have witnesed this first hand, so it makes sense. the first cam i had in my 65 was a fireball 290 which had lots of torque and a lobe separation of 106. my curent cam is a powermax 272 which makes much more top and power and builds more mid to upper torque. it has a lobe separation of 112 and is designed to work with a power adder. also split duration and lift cams work better with power adders typically you want 10 deg more duration and at least .010 more lift on the exhaust to help the spent mixture escape better. | | Thread Tools | | | | Display Modes | Linear Mode |
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