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Old 03-17-2012, 09:14 PM   #1
spikebot 81
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Default elgin cam

Could someone please help me with a camshaft application. I just bought a sbc long block from a guy that had the engine stored for 2 yrs and never installed. He had no paper work on the engine however I was able to find all the build info without tearing the engine down. I did have to take the cam out to id it and it is a Elgin 1120P. What will this camshaft be best suited for? Thanks for your help

http://catalog.elginind.com/app/Engi...gh+Performance

Last edited by spikebot 81; 03-17-2012 at 09:16 PM. Reason: spelling
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Old 03-17-2012, 09:41 PM   #2
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CS1105R
1800-4400 RPM Range
283 intake/286 exhaust Adv Dur
Duration @.050 209 intake/216 exhaust
Valve Lift .435intake/.455 exhaust
Lobe C/L 112

This is the Sealed Power version of that cam. (Melling, Elgin, Sealed Power, Summit Racing, Jeg's, I think they all get their cams from the same source and sell them under their own brand.) 1800-4400 rpm power range is claimed, looks like a good street cam in the right engine. If you don't want it, I'll give you twenty bucks for it!


Keep the shiny side up!
Scott
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Old 03-18-2012, 02:25 AM   #3
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112 centerline is too much overlap? I must be missing something here. I don't claim to be an expert by any stretch of the imagination, but that sure looks like a pretty mild cam to me, (and I'm pretty conservative when it comes to cam timing) not much bigger than what some folks call an "RV" cam. (204/214 @ .050", 278/288 adv, .420/.442 lift, 112 centerline)
Maybe I'm looking at the wrong cam!


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Old 03-18-2012, 10:51 AM   #4
Little Mouse
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283 + 286 = 569. 569/4 = 142. 142 - 112 LSA = 30. 30 x 2 = 60 overlap.

278 + 288 = 556. 556/4 = 139. 139 - 112 LSA = 27. 27 x 2 = 54 overlap

how about a mythical 107 lsa thumper cam LOL.

283 + 286 = 569/4 = 142. 142 - 107 LSA = 35. 35 x 2 = 70 overlap. same cam but tight lSA, big difference in overlap.

Or add the IO and EC.

They don't consider it a race cam till it hits 90 overlap and above.

Last edited by Little Mouse; 03-18-2012 at 11:36 AM.
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Old 03-18-2012, 02:03 PM   #5
Solid LT1
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That cam is not a very big cam, looks like a "marine" grind to me, should work fine in any Vette won't make big HP numbers or rev high, should work great with auto trans and A/C.

Elgin and Melling are some of the brands and grinds you will find in Edelbrock boxes where the double the price by re-packaging someone's product and put it in a shiny new box.

Last edited by Solid LT1; 03-18-2012 at 02:05 PM.
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Old 03-18-2012, 02:24 PM   #6
spikebot 81
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Good info eveyone. I'm not opposed to buying a camshaft that would better fit my application. I'm just camshaft dumb and didnt really know how this elgin cam would run with the engine setup.
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Old 03-18-2012, 02:48 PM   #7
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Quote:
Originally Posted by spikebot 81 View Post
Good info eveyone. I'm not opposed to buying a camshaft that would better fit my application. I'm just camshaft dumb and didnt really know how this elgin cam would run with the engine setup.
Well, let's hear a little about the engine it's in.


Keep the shiny side up!
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Old 03-18-2012, 03:26 PM   #8
Little Mouse
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You have flat top pistons 76 cc chamber head with your rebuild. The L/82 had the same combo of piston and head. Its cam had 224 at .050 intake duration. By comparison the elgin cam is much milder at 209 .050. Kind of in between a .195 .050 L/48 cam and L/82 cam. Should make for a nice cruiser street car.

Last edited by Little Mouse; 03-18-2012 at 03:34 PM.
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Old 03-18-2012, 03:27 PM   #9
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Ok. 355 sbc with cast iron pro topline heads 180cc intake 64cc chambers, speed pro dished pistons compression 9.6 to 1. I have a 2101 performer intake with edle 600cfm carb in good shape from the blown engine.. Long tube 1 5/8 headers 2 1/2 duals to magna flows no cats

The new engine has stamped steel rockers that are unmarked other that a W stamped on the tip.. I do have a set of 1.6 roller tips in good shape from the old engine which by the way had aprox 30,000 mile on it.

I have a brand new 200r4 trans built to handle 400hp with 2200 stall

Last edited by spikebot 81; 03-18-2012 at 03:38 PM.
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Old 03-18-2012, 11:09 PM   #10
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Quote:
Originally Posted by spikebot 81 View Post
Ok. 355 sbc with cast iron pro topline heads 180cc intake 64cc chambers, speed pro dished pistons compression 9.6 to 1. I have a 2101 performer intake with edle 600cfm carb in good shape from the blown engine.. Long tube 1 5/8 headers 2 1/2 duals to magna flows no cats

The new engine has stamped steel rockers that are unmarked other that a W stamped on the tip.. I do have a set of 1.6 roller tips in good shape from the old engine which by the way had aprox 30,000 mile on it.

I have a brand new 200r4 trans built to handle 400hp with 2200 stall
So now your saying your changing the heads to 64cc chamber iron heads, flat top pistons, better low gear trans with mild converter. You need to ditch the 209 .050 duration elgin cam go up in duration and lift. Your raising the compression up now high enough with iron heads your going to have a problem with detnation using the elgin cam. Keep a wide LSA 112/114 it will close the intake valve a little later help further to bleed off some compression and widen your power band.

With a performer intake and 600 carb its obvious your not after every once of power. Play it safer with a flat tappit cam and use one of the slower ramp cams none of that extreme energy stuff like comp sells or other companies versions of the cam.

Last edited by Little Mouse; 03-19-2012 at 12:01 AM.
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Old 03-19-2012, 12:29 AM   #11
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Cardo your hero vizard says a race cam starts at 90 degrees of overlap. He is pretty knowlegable about stuff no doubt.

I had a cam in my street car with 87 degrees overlap 108 LSA power started at 4500 but it was 265 at .050 intake duration. Think maybe thats why the power started a little high LOL. It had none of the problems you described with 87 degrees of overlap. low gear was 2.20 with 3.36 in the back.

I'm sure that bad *** 209 .050 duration 1600 to 4400 rpm will do him in lol.

Last edited by Little Mouse; 03-19-2012 at 12:56 AM.
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Old 03-19-2012, 09:54 AM   #12
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Quote:
Originally Posted by cardo0 View Post
Performance Camshafts

By Dimitri N. Elgin
Elgin Cams
Redwood City CA

In standard engines, valves are open together for only 15-30 degrees of overlap. In a race engine operating between 5000 and 7000 rpm, the overlap period is more like 60-100 degrees. The penalty for so much overlap in a street engine is very poor running at lower rpms, when a lot of the intake charge has time to sidetrack directly out the open exhaust valve. Mileage goes South. Heads overheat from fuel burning in exhaust ports. The engine runs hot. The exhaust system gets fueled like a blowtorch. The tailpipe turns white. Catalytic converters fry. The buyer blames the cam grinder.....
... Balance power goals with other requirements for the intended usage, such as idle quality, low-speed throttle response, fuel economy, and smog test compliance.

You missed the most important spec on that cam card Scotty - the overlap in cam degrees.

Good night,
cardo0
CS1105R
1800-4400 RPM Range
283 intake/286 exhaust Adv Dur
Duration @.050 209 intake/216 exhaust
Valve Lift .435intake/.455 exhaust
Lobe C/L 112

This is a very mild cam. It would be a good upgrade for a bone stock , standard 8.2 to 1 compression L-48 if you decided to upgrade your cam in 1975. It is an old school grind with real lazy ramps. This is in no way or any stretch of anyones imagination anything resembling a race cam.

This is vizard's overlap chart.
10* - 40* towing
30* - 60* ordinary street
50* - 75* street performance
70* - 90* street/strip
85* - 100* race
95* - 115* Pro race

You also need to realize that advertised duration is a seat to seat measurement. Some cams advertised duration (OEM) numbers are actual seat to seat. This was the standard used by the car manufacturers. An example would be an L-82 cam. This is the FACTORY numbers on this cam and the cam Chevy used as a street cam in a 9 to 1 compression motor.
312/312 advertised duration
222/222 duration @ .50.
450/460 lift
114 LSA.
Using your reasoning and Vizards chart the L-82 cam is a maximum Street/strip or midlevel race cam. Ask anyone who has ever had one if this is valid.
I would bet this is the way the Elgin cam was measured. Then some companies started using .004 lift for a seat to seat number, others use .006 lift and the modern solid lifter cams use .020 to .020 lift numbers as the basis for their advertised duration numbers. If this cam was measured at .006 lift as seat to seat numbers the overlap could well be 20,30 or 40 at most.

Duration @ .050 is a much better basis for the mannerisms the cam will have in the car. This is a 209 duration @ .050 cam with 112 LSA and a 1800 to 4400 RPM operating range. This is a basic, low compression street cam. The reason the operating range is narrow with a 112 LSA is the very lazy ramps. A faster ramp (roller) opens up the operating range. You are being confrontational with a group here that are grasping basic cam concepts much better than you are.

Good night,
Mako

Last edited by 63mako; 03-19-2012 at 10:13 AM.
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Old 03-19-2012, 11:19 AM   #13
Little Mouse
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Thanks for putting up the vizard chart.

I have it somewhere was not wanting to dig it up.

I had a brand new 78 with the L/82 ordered the car. Very mild car easy to drive. Badly underpowered but thats what all cars were like back then.

Last edited by Little Mouse; 03-19-2012 at 11:24 AM.
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Old 03-19-2012, 12:58 PM   #14
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Some of these numbers that you guys are throwing around don't mean a whole lot to me, like overlap. I mean, I understand what it is, but I don't really have the experience to know how much overlap is good for what rpm range, etc., I was just comparing the specs to other cams that I know have a rep for being mild cams. Most people who's opinion I trust consider any cam with less than around 220 degrees @ .050" and LSA above 110 to be a pretty reasonable cam. Definitely not what you'd call a "bottom of the page" cam.

You have decent heads and a little bit of compression, 2200 stall converter, If you have a little bit of gear out back, say 3.55 or better, you might want to think about kicking the cam up a notch, something like this:

http://www.summitracing.com/parts/SUM-K1103/


Keep the shiny side up!
Scott

Last edited by scottyp99; 03-19-2012 at 01:02 PM.
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Old 03-19-2012, 12:58 PM
 
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