Camshaft
So i know what a camshaft is, but there is alot of talk about different sized cams and everything. what exactly is the purpose of an aftermarket cam? and what is the difference between them? :popcorn:
|
Well, this is a very broad question and you can find out a TON of info just by researching a little. But I'll try my hand in summarizing the basics. The different sizes and combinations are to achieve what you want your car to do. Say you want a car mainly for the dragstrip on the weekend and its not your daily driver, then you will most likely want more duration and lift than you would if you want your car to be just an everyday cruiser/streetcar. Before you start considering cam options, you first need to consider what you want the car for.
The goal of an aftermarket cam is just like anything else... to get more hp (DUH!!). But it will come with some disadvantages. These days, alot of dudes just want to put the biggest stick they can in their weekend starbucks cruiser so that they can get a choppy idle and shake the ground when the pull up at 5 mph (sorry old guys) but this is NOT WHAT YOU WANT TO DO! With aftermarket cams you need to consider a few cons: The bigger you go, the longer its going to take to your rpm range. Too big of a cam and you lose your low end which is your car's "peppyness" which is 95% of what makes a car fun. With any aftermarket cam i would suggest some lower gears (3.90's, 4.10's) to get you back some of that low end you'll lose and help you out with getting to your rpm range. Most aftermarket cams will make your car surge at low rpms. This is b/c of the more lift and duration of the cam is pulling vacuum. Once again, this is another burdon but you get used to it and learn to drive above it. But you just cant cruise at 70mph in 6th at 1300rpm with an aftermarket cam. Last thing, a 114 LSA is your best friend!!! Sure a 111 or 112 will give you a good chop, but who cares about that crap if your car is too rough for a fun drive. These are just a few tips that i would consider before even thinking about a cam. Figure out if you want your car to be for: race, street, or a little of both and go from there. |
Quote:
The difference between camshaft is lobe design, lobe lift, lobe center line, and more the best bet is to find out what you want the car to do and then call one of the manufactures of cams tell them what you want to do and let them help you find a cam. |
thanks! this really helps alot. :chevy:
but is there always a choppy idol sound when the engine is cammed? |
Quote:
That is one reason why you dont want or cant run power brakes on cars with very large cams because you do not have the high negative pressure in the intake manifold you are getting more postive pressure. You can increase and decrease overlap many different ways but I would choose a cam based only on overlap. You can have one cam on a 115 LSA and another on a 106 LSA and they could have the same overlap depending on what the duation @.050 is. |
Good read, and sorry if I missed it, but:
What is surge (at low end)? It was said that camming typically loses the low end. Then it was said that the car will "surge" at low end. What is LSA? You need to pick your cam based on how you want to use your car. Could someone site an example of how to pair a cam with driving behavior? If I want to use my car as a safe/reliable daily driver, then it would be in my best interests to lean towards a XXX sized cam. This is because XXX? Also, if you go with XXX sized cams, you will also benefit more from XXX sized gears. This is because XXX. Sorry for all the questions. It goes to show you that the explanations above so far have been good enough to peak the interest of learning new things! |
Quote:
LSA is lobe seperation angle. It sounds like you want your car like most everyone else does... to have good street manners and to be able to drive and have fun with it without worry of driving "around" the cam too much. With that said, if i were you i would take a long hard look for a referance point at TSP's (texas speed and performance) 224R and 228R cams. The 224R is famous for being a great daily driver cam. For your desire to have the car drive as smooth as possible, i would suggest when looking at cam sizes to stay below .230 or .235 duration for both intake and exhaust and definitely stay below .600 lift. The 224R is .224/.224 and like .588 lift i think. And whatever you do, dont let anyone talk you into a 111 or 112 LSA. You want 114 at all cost. Now when you go to research cams, you find most of them bigger than the #'s i just said. And it is tempting, to get a bigger cam than you actually need. But if you stay within your limits you'll get everything you want and still have a fun car. Oh yeah, about gears. For a street car just pick something lower than stock and run with it. Dont like em, change em out. I would say 3.90's would be perfect for a cam like the 224R or 228R. |
Quote:
|
Here is a nice write up by CamaroSpike23
http://www.camaro5.com/forums/wiki.p...amshaft+Basics |
Thanks g-town!
Thanks for the link too Milk. Good n00b section! |
All times are GMT -5. The time now is 08:40 AM. |
Powered by vBulletin® Version 3.8.9 Beta 4
Copyright ©2000 - 2024, vBulletin Solutions, Inc.