i had a post on this a while ago but i cant find it. but what is the problem if i replace my stock cam with a comp cam without doing anything else to my car?

 

Im assuming your talking about doing other things inside the motor besides just swapping the cam.

And in all reality you can just change the cam... however its always a good idea that with a new cam you at leastget new lifters. The old ones are worn into the old cam and getting new lifters for a new cam is just a good idea. If your going for a big lift cam youll need to change out the springs to get a higher spring rate and a spring that support the larger lift. And if you want to keep going from there hardened pushrods are relatively inexpensive and also a good investment. Then if you want new rockers....[sm=smiley29.gif]Its a deadly circle of "Its just a couple hundred bucks" that all adds up

 

well the only other thing i would do is maybe a new cat back and some headers

 

With a full roller assembly (which the LS1 is) you don't necessarily need to replace the stock lifters because they don't get "worn in" to the cam like the tappet cams did. If you do a cam swap remove the lifters and make sure they are all in a good functioning state, but you don't have to replace them. You always want to match valve springs to the new cam.

 

i did not even remove my lifters. I just stuck rods in the oil holes on the front of the motor to hold them in place during the cam swap.

 

camaro dude the cam only swap is not recommended especially in a computer controlled car unless you use a mild and or computer compatible ground cam. changing one part on your air pump will never have the desired effects that a complete parts matching add ons will. if you decide to install a non computer compatible cam into your computer controlled car i will guarantee things wont work right and you may well lose power as a result if not destroy stuff kurt

 

pilot, i have to assume you are talking about the valve train.... because its the only part to worry about with more aggressive cams. with the wicked cams there is a tendancy for the car to drool on itself at idle a little and to lean out up top, because of the increased airmass and locked in WOT map respectively, neither of which will be tuned, but with the mid-high level cams its not a huge deal, just something to be aware of. there are alot of people that have run larger cams untuned or just "hand tuned".


the real issue is from overcamming a car. Large duration and high lift cams shift the power band higher in the RPM. my cam doesnt kick in until over 4.5k, while some will still make power after 7k. now, if you do nothing else to the motor you run into a problem. the cam cannot make power down low, and the engine cant breath well enough up top to let the cam do its job where it wants to. so you end up just not making power across the board. i dont view it as parts matching so much as just making sure everything is openned up enough. if we want to use the air pump analogy its like you have a small pump with small hoses, and you put a more powerful pump in, but it just strains because it cannot suck enough in the one end to put anythign out the other end.

 

[&:] specter anytime you change cam profiles you will change emissions and vacuum characteristics of the motor. i realize these can and should be compensated for to retain emissions and computer controls. my point is that sticking a cam into a car that produces characteristics outside of the computers ability to compensate will leave one with lots of problems and a cam large enough to produce real noticeable gains will require other work and or parts. id like to see someone stick a real radical lumpy idle wicked lift and duration cam into an ls1 or lt1 and do nothing else and see what happens

we all know our air pumps parts are designed to work as a collection of parts to achieve full potential kurt

 

the components you are talking about are all stock on my car, i havent even uploaded the new tune yet, only scanned it. the only thing changed are the springs and their components, but those are not computer controlled. how big do you need, i can give you a couple guys that have lifts over .600 on a stock tune

 

another thing that i keep in mind is that probably most of the people who ask questions on this site do not have the knowledge base you and i have. lots of questions are coming from inexperienced hot rodders who have purchased thier first computer controlled car but still have the throw a carb, cam and header at it mentality and dont even consider that emissions werent a concern back in the good old days and in most areas now they need to pay attention to emissions and try not to melt down thier expensive cats while making mods.


i see lots of this type of question from the crowd i mentioned above and i want to make it clear that the old days are gone when it comes to the new stuff unless you have a much fatter wallet kurt