Which kind of cam is better?
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From: garfield, nj
Car: 86 Z28
Engine: 355 carbed
Transmission: t-5
Which kind of cam is better?
I am going to be doing a heads and cam swap on my car in the next month or 2 and was wondering how hard it is to change the cam. What is the difference between the Hydrolic ller and Regular Hydrolic cams? Which type is better? Any help would be great I was looking at Comp Cams .477"/.480" with a 268 grind, rpm range: 1600-5800
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From: Someone owes me 10,000 posts
Car: 99 Formula
Engine: LS1
Transmission: T56
Axle/Gears: 342
A hydraulic roller will be better as there is less friction = more HP. I'm not sure if it will slide right in though, without some mods, I'll let someone else answer that.
If you're changing heads, changing a cam at the same time will be a lot easier.
If you're changing heads, changing a cam at the same time will be a lot easier.
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From: Jackson County
a roller is better all the way around, it'll be smoother and still have more aggresive profile than a flat hydrolic. if you can use one depends on the block you have, since you never said. if it's not made for a factory hydrolic rooller you can't run one, without lot of work. easier to find another block.
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From: Readsboro, VT
Car: 85 IROC-Z / 88 GTA
Engine: 403 LSx (Pending) / 355 Tuned Port
Transmission: T56 Magnum (Pending) / T5
Axle/Gears: 3.42 / ?
A little more explanation. You make more power by getting more air in and out of the combustion chamber. The cam's job is to open the valves to allow this to happen. With a cam, your choices for getting more air in and out include opening the valve higher, opening it longer, and opening it faster, holding it open at its maximum position longer, then shutting it faster. The last option is generally the best, because the other two will create more overlap (having intake and exhaust valve open together). The problem is, you can only make a hydraulic cam so steep before the lifter won't be able to ride up it smoothly, and it will put severe stress on the lifter, rocker & spring. With a roller cam, you're dealing with a round lobe instead of a flat one, and this allows you to provide a much steeper profile on the cam, i.e. open and close the cam much faster.
The benefit to roller cams is due mostly to the better profiles you can run, and not so much the reduced friction.
The benefit to roller cams is due mostly to the better profiles you can run, and not so much the reduced friction.
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A little more explanation. You make more power by getting more air in and out of the combustion chamber. The cam's job is to open the valves to allow this to happen. With a cam, your choices for getting more air in and out include opening the valve higher, opening it longer, and opening it faster, holding it open at its maximum position longer, then shutting it faster. The last option is generally the best, because the other two will create more overlap (having intake and exhaust valve open together). The problem is, you can only make a hydraulic cam so steep before the lifter won't be able to ride up it smoothly, and it will put severe stress on the lifter, rocker & spring. With a roller cam, you're dealing with a round lobe instead of a flat one, and this allows you to provide a much steeper profile on the cam, i.e. open and close the cam much faster.
The benefit to roller cams is due mostly to the better profiles you can run, and not so much the reduced friction.
The benefit to roller cams is due mostly to the better profiles you can run, and not so much the reduced friction.
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From: kentucky
It is understandable that the air must enter and exit the cylinder rapidly, but I always understood cam functions as allowing more fuel mixture to be brought into the cylinder. Have I misunderstood all these years 
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From: Readsboro, VT
Car: 85 IROC-Z / 88 GTA
Engine: 403 LSx (Pending) / 355 Tuned Port
Transmission: T56 Magnum (Pending) / T5
Axle/Gears: 3.42 / ?
Originally posted by RICHRAD
It is understandable that the air must enter and exit the cylinder rapidly, but I always understood cam functions as allowing more fuel mixture to be brought into the cylinder. Have I misunderstood all these years
It is understandable that the air must enter and exit the cylinder rapidly, but I always understood cam functions as allowing more fuel mixture to be brought into the cylinder. Have I misunderstood all these years
On a port-injected car, the fuel is fired directly into the intake runner of the head, so the air has less work to do in order to bring it into the combustion chamber, but it's still more or less the same situation.
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From: Someone owes me 10,000 posts
Car: 99 Formula
Engine: LS1
Transmission: T56
Axle/Gears: 342
Originally posted by twiztidz28
So even though my car is Carbed i could still go with a roller cam? Is taht a good choice. I want power to around 5500 RPM
So even though my car is Carbed i could still go with a roller cam? Is taht a good choice. I want power to around 5500 RPM
The Comp 268XE makes power to what you want, just to let you know.
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