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Discussion Starter · #1 ·
OK I am confused with the cams. I was told to get a CC 503 cam but to get the 276hr-14 instead of the 276hr-12 grind because it would work better with a heavy car like mines and better driveability.

The cc 503 with the 276hr-14 is as follows:
230/230, .540/.540 with 1.6 rr, 114 lsa

the cc 503 276hr-12 is:
224/230, .540/.544 with 1.6 rr, 112 lsa

what would be the difference between these two cams? how would the powerband be with these cams? Would the 114 lsa be better for a street car?
 

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Somebody is giving you poor advice.
The standard 503 cam, 224/230/112 will be the better performer, especially in a 350.
Run at least 3.73 gears and 3000 converter with it.
 

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Somebody is giving you poor advice.
The standard 503 cam, 224/230/112 will be the better performer, especially in a 350.
Run at least 3.73 gears and 3000 converter with it.
Pat, what cam (specs) do you run? Would it be a good choice for a street driven car? Also, what is your valve train setup?

OP, listen to Pat on this!
 

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Stumpy, My cam is a Custom from AI, in between their listed 226/234 and 230/238 cams. Lift is .600-.610, which tells me the lobes are slightly more aggressive than both of those listed offerings. I'm running the big block beehive springs, the Pacalloy 1220's from AI.
For mostly street driven, I'd step back to the 226/234 cam. I shift at 7000 to get the most out of mine. It's definitely streetable, but the 226 would give you a lower rpm useable powerband on the street, and wouldn't wear out the springs as quickly. The F-body guys are running fast with it on both stock and ported heads.
 

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Discussion Starter · #5 ·
i just got the cam back from the machine shop and looked on the end of it and it is a 276hr-12 cc503 cam. i will be running it with a 3000 stall 10" converter and the 373s. bout to install it now and try to fire it up.
 

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FWIW, that is the exact same cam, in my old stroker, which now resides, with my old, ported LT1 heads, in my buddy's stroker Impy.:)

It has gone 12.00's in a full weight Impy, with 3.73 gears, and 3600 stall. YMMV
 

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Stumpy, My cam is a Custom from AI, in between their listed 226/234 and 230/238 cams. Lift is .600-.610, which tells me the lobes are slightly more aggressive than both of those listed offerings. I'm running the big block beehive springs, the Pacalloy 1220's from AI.
For mostly street driven, I'd step back to the 226/234 cam. I shift at 7000 to get the most out of mine. It's definitely streetable, but the 226 would give you a lower rpm useable powerband on the street, and wouldn't wear out the springs as quickly. The F-body guys are running fast with it on both stock and ported heads.
Pat are you running pump gas with that ET? I'd love to be in that neighborhood once I get my motor together.

Wonder if that will pass CA SMOG :(
Don't want to put my baby on the trailer quite yet.
 

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Stumpy, My cam is a Custom from AI, in between their listed 226/234 and 230/238 cams. Lift is .600-.610, which tells me the lobes are slightly more aggressive than both of those listed offerings. I'm running the big block beehive springs, the Pacalloy 1220's from AI.
For mostly street driven, I'd step back to the 226/234 cam. I shift at 7000 to get the most out of mine. It's definitely streetable, but the 226 would give you a lower rpm useable powerband on the street, and wouldn't wear out the springs as quickly. The F-body guys are running fast with it on both stock and ported heads.
Pat, question, for a daily driver and track car is the 503 cam with a 112 or a 114 lob seperation better and does that little hurt overall performance?
 

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Barry, Definitely the 112 LSA. And I'd bump it up to a 106 installed ICL, rather than the "drop-in" 108 ICL.
It's not a compromise for a track car OR for a daily driver car.
 

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Pat, question, for a daily driver and track car is the 503 cam with a 112 or a 114 lob seperation better and does that little hurt overall performance?
I've had a higher lift version of the 503 cam in both my cars:

224/230 ---- .605"/.622" lift ---- 114* LSA with 4* advance in the grind.

With the Comp Cams grinds, a lower LSA usually will result in more peak power. I will say that there may be some HP left on the table with the above cam but I won't say there was much (or any) torque left on the table, however......particularly average torque through the power curve.

Also, the above cam has -4* valve overlap so the idle was smooth as hell and gas mileage was exceptional (24MPG hwy in a 396ci with 3.73 gears).

I'd say that the less overlap, arguable the more 'comfortable' on the street and the 114* LSA will typically have less overlap that a comparable 112* cam. That said, I see no significant issue with a 112* LSA.....which many people will still tell you is very, very tame.

FWIW.....

KW
 

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I've had a higher lift version of the 503 cam in both my cars:

224/230 ---- .605"/.622" lift ---- 114* LSA with 4* advance in the grind.

With the Comp Cams grinds, a lower LSA usually will result in more peak power. I will say that there may be some HP left on the table with the above cam but I won't say there was much (or any) torque left on the table, however......particularly average torque through the power curve.

Also, the above cam has -4* valve overlap so the idle was smooth as hell and gas mileage was exceptional (24MPG hwy in a 396ci with 3.73 gears).

I'd say that the less overlap, arguable the more 'comfortable' on the street and the 114* LSA will typically have less overlap that a comparable 112* cam. That said, I see no significant issue with a 112* LSA.....which many people will still tell you is very, very tame.

FWIW.....

KW
WOW the 4* advance provided better gas mileage, this is incredable. And it tames it down which I have issues with now. Thanks!
 

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Barry, Do you already have one of these cams? If you do, then some of this is a moot point. If you don't, then don't crutch a cam choice, that is really not right for your needs, just by widening the LSA.
 

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Barry, Definitely the 112 LSA. And I'd bump it up to a 106 installed ICL, rather than the "drop-in" 108 ICL.
It's not a compromise for a track car OR for a daily driver car.
Pat, I do not have a cam yet and the one in the car was circle ground and not really working for me so I want to go with something proven like the CC503. So Let me get this straight, get a CompCam ground in the 503 format keeping the LSA at 112 and changing the ICL to 106. It was mentioned about a 4 degree change. I have hear that degree change can move the power curve into the higher RPM or down lower. I do not want to rev this thing to high so would a -4 degree also be good or do I have it backwards. Because of my strocker kit I have to have it circle ground for clearance. I am also running lower compression. Appreciate your feedback.
 

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Pat, I do not have a cam yet and the one in the car was circle ground and not really working for me so I want to go with something proven like the CC503. So Let me get this straight, get a CompCam ground in the 503 format keeping the LSA at 112 and changing the ICL to 106. It was mentioned about a 4 degree change. I have hear that degree change can move the power curve into the higher RPM or down lower. I do not want to rev this thing to high so would a -4 degree also be good or do I have it backwards. Because of my strocker kit I have to have it circle ground for clearance. I am also running lower compression. Appreciate your feedback.
Barry .. I run a 503 with a 110LSA and a 108 ICL ground in and it's pretty mild.
 

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.....then don't crutch a cam choice, that is really not right for your needs, just by widening the LSA.
Pat.......the widened LSA is not a crutch in this case; particularly when we're talking about a moderately sized cam like these. The purpose of manipulating valve events is to achieve certain cam charactoristics.

In this case, achieving minimal overlap has very real charactoristics (benefits) that some may desire. And achieving this minimal overlap results in a widened LSA.

It's not all about peak power.....and as stated, I doubt that a non-racer will notice the slightly lowered peak horse power with a 114* LSA vs a 112* or even a 110* LSA cam in this general 'size' range.

KW
 
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