Stage 3 Comp Cams
Senior Member
Joined: 08-13-05
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From: the glove
they have a blower cam on the site but how would there grind be any differant....we cant realy make use of a hig rpm cam becasue the redline is low and sence its a blower the boost is almost always on so how would an aftermarkit cam be diff......i kno it is i just dont get it...thanks
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Joined: 03-20-05
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From: Rutherford, NJ
Originally Posted by Rusty
Camshafts (or cams) are what control your intake and exhaust valves in each cylinder.
Cams are driven by the timing belt. When the cam turns, it closes the exhaust valve, and opens the intake valve...or vice versa. This is all dependent on the timing and tuning of the car. The cams are ground to certain parameters that determine the length of time that each valve is open and the timing in which they close/open. As you probably know, for combustion in a cylinder, air and fuel are let in through intake valve into the cylinder. Then it closes and the spark plug goes off as the piston pushes the air/fuel up, creating combustion. Then the exhaust valve opens, exhaust gases escape and the piston is pushed down.
Aftermarket cams are designed to allow more air/fuel into each cylinder, usually at higher rpms. The more radical the cam, the better top-end performance you have, because the cams are then designed to be running at 5000+rpm or whatever. This usually results is poor idle quality. For example, when you go to the track and see pro street cars run, the idle sounds like its either going to die, or its real "lumpy." That means they have a very aggressive cam.
I hope that answered your question.
Cams are driven by the timing belt. When the cam turns, it closes the exhaust valve, and opens the intake valve...or vice versa. This is all dependent on the timing and tuning of the car. The cams are ground to certain parameters that determine the length of time that each valve is open and the timing in which they close/open. As you probably know, for combustion in a cylinder, air and fuel are let in through intake valve into the cylinder. Then it closes and the spark plug goes off as the piston pushes the air/fuel up, creating combustion. Then the exhaust valve opens, exhaust gases escape and the piston is pushed down.
Aftermarket cams are designed to allow more air/fuel into each cylinder, usually at higher rpms. The more radical the cam, the better top-end performance you have, because the cams are then designed to be running at 5000+rpm or whatever. This usually results is poor idle quality. For example, when you go to the track and see pro street cars run, the idle sounds like its either going to die, or its real "lumpy." That means they have a very aggressive cam.
I hope that answered your question.
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Joined: 11-15-05
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From: Egg Harbor Township, NJ
Originally Posted by memphisr24
Thank you. That cleared it up for me. I understood every word you said belive it or not. Website's such as these are very useful to me. If it wasn't for this site and all of its members, I wouldn't know what was out for the cobalt or what different parts do to the engine.
back to the cams...
Deciding on what cams to get is very tricky. Cams are a pain in the dick to install and affect the daily driveability of the car. Usually stage 1 or stage 2 cams are streetable with little difference in driveability. It's when you get to the aggressive stage 3+ cams that you have problems driving everyday. It is at this point where you need to figure out exactly what the car is going to be used for and what you hope to attain by installing the cams.
Member
Joined: 04-20-05
Posts: 373
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From: NJ
I have a 2.2L eco at my other house... i took most of it apart, the one side wasn't that hard at all to take off, and u don't have to remove the head to doit, the other side however, i still can't get off cuz of sum kinda pump or sumin holding it in. my $.02
any update testers? would like to UPGRADE from stage 1s to stage 2s please.
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Joined: 07-03-05
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From: Port Orchard WA
Ok as some of you know I am usually on the rl forums but I have a 2.0 spare block and I am doing a perf build. I am working with sms and I have been doing alot of research over the last two months.
1. The stock valve train is having some prob's now, I am in pretty good with my dealers service manager. The prob's they are seeing are valve floating with stock cars and binding valves due to excessive carbon deposites. Solution use a oil catch can between valve cover vent and the intake. But be sure to hook it up so there is a line going from the vc to the catch and the vent of the catch to the intake. This is to evacuate any fuel vapor from the crankcase in order to avoid a crankcase explosion. This is why not to just put a filter there instead. IT NEEDS VACUME...
2. Jessel makes a killer setup for the ecotec but oh baby its $$$ try $2500 just for the rockers and lifters. For what we need this is way overkill these setups are used on the pro cars not daily drivers.
3. The question about the larger ratio rockers, No nobody makes any for us and probably wont due to the very small window of operation for these valves. But on the other aplications that they are made for they work very well ( I have used them on several v8's). BTW are stock ratio is 1.75 which is fairly large already.
4. The only valve springs that I can find are from ferrea I talked to their engineer and they have what we need including titanium retainers . The jbperf stuff I have no idea what they are using but by the price doesnt sound like ferrea because they are like 300 for springs and 300 for retainers and 150 for seats. These prices are just list so they may be cheaper with some haggling (yes I'm on it).
I am worried about the jbperfs because its well known that some socall perf guys will add shims under the stock spring to increase seat pressure. This only ok to a point but our factory stuff isnt rated for this and could be a very bad ending with coil bind and fatigue vs the ferrea stuff that is engineered for it. Personally I'm not going to chance it.
1. The stock valve train is having some prob's now, I am in pretty good with my dealers service manager. The prob's they are seeing are valve floating with stock cars and binding valves due to excessive carbon deposites. Solution use a oil catch can between valve cover vent and the intake. But be sure to hook it up so there is a line going from the vc to the catch and the vent of the catch to the intake. This is to evacuate any fuel vapor from the crankcase in order to avoid a crankcase explosion. This is why not to just put a filter there instead. IT NEEDS VACUME...
2. Jessel makes a killer setup for the ecotec but oh baby its $$$ try $2500 just for the rockers and lifters. For what we need this is way overkill these setups are used on the pro cars not daily drivers.
3. The question about the larger ratio rockers, No nobody makes any for us and probably wont due to the very small window of operation for these valves. But on the other aplications that they are made for they work very well ( I have used them on several v8's). BTW are stock ratio is 1.75 which is fairly large already.
4. The only valve springs that I can find are from ferrea I talked to their engineer and they have what we need including titanium retainers . The jbperf stuff I have no idea what they are using but by the price doesnt sound like ferrea because they are like 300 for springs and 300 for retainers and 150 for seats. These prices are just list so they may be cheaper with some haggling (yes I'm on it).
I am worried about the jbperfs because its well known that some socall perf guys will add shims under the stock spring to increase seat pressure. This only ok to a point but our factory stuff isnt rated for this and could be a very bad ending with coil bind and fatigue vs the ferrea stuff that is engineered for it. Personally I'm not going to chance it.
New Member
Joined: 07-03-05
Posts: 151
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From: Port Orchard WA
Also to add somebody said something about the overlap. Our cams DO NOT HAVE THE OVERLAP in the grind due to its a dual cam. You control the overlap with adj cam gears (for those who dont know overlap is the time the intake and exhuast valves are open at the same time). Now thinking about it if you where using non adj gears the overlap could be put in the grind but why would you want to instead buck up and get the gears.
New Member
Joined: 07-03-05
Posts: 151
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From: Port Orchard WA
Heres our factory specs from my spare engine. only pay attention to the top table of each measurement and the overlap is wrong you must measure this with the cams in the block and a degree wheel.
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Joined: 03-11-12
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From: Mobile AL
What did you set your can timing at?
i have to give you guys a review on the comp cams. i had a comp cam in my civic and i have to say that the cam was one of the best investments i made. i had a lot of head work that went along with the cam but man it dramatically increased my top end. now my idle was shot to hell. lol. it loped really hard, but i had the race cam and not the street cam. comp cams knows what they are doing!!!
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