who was that meant for

now what does under the curve mean.

 

It was meant for "you". Just trying to make sure you are aware of what you are getting into. Not meant in any other way.

Airflow to the engine is determined by the opening (lift) of the valve, and the amount of time it is open. Two cams can have identical duration and maximum lift, but have completey different "profiles"... a plot of lift in inches vs. degrees of rotation. If you plot that curve, measuring the "area" below the plotted curve (and including the flow capabilites of the head for each lift value - but lets not complicate things), the more "area" under the curve, the more airflow you are going to get. Open the valve "slowly" and it takes longer to get to higher lift and higher airflow numbers. Open the valve with a quick "snap" and the air starts to flow sooner. Integrating lift with rotation determines the "area under the curve"... more is better.

A hydraulic lifter has a problem with moving the mass of the valve train very quickly. A soild lifter does not. But to move quicker, while keeping the valvbe train motion under control, the spring pressure on the solid roller needs to be much higher than on the hydraulic roller. On the other hand, you simply can't increase spring pressures to much on a hydraulic lifter, or you can "collapse" the lifter.

And, just because you "can" make the ramps more aggesssive, doesn't necessarily mean they "did" make the ramps more agressive. You need to look at the specific profile of the cam. Maybe this 306 (if its "solid) has no more area under the curve than the hydraulic version of the same cam. I honestly don't know the specific profile/lobe design of either.

 

ok i understand some of it now. thanks alot.

i just clled comp cams and he couldnt tell me anyhting about the cam with the grind# cuase thats all i have (# cs306s-10). so iwill have to ask the guy selling. he bought it for his car (lt1) but the guy at compcams said if it was made for a small chevy it will not work. is this true. he was also kind of a *****.

 

so now i know its a solid roller. but now will it run the water pump and opti.

 

Hmm I'm woundering why comp 986 springs are included in this "kit". Those are for a hyd roller.

 

The nose of the LT1 cam is different than the standard SBC Chevy cam. It has a bevel, and includes provisions for driving the OptiSpark distributor. Once you get a cam for an "LT1", it doesn't matter if its hydraulic or solid roller... it has the same nose, and interfaces with the timing gears the same way, so the water pump will work without regard to lifter type. The Opti is the same way, but the 93-94 cam nose is different than the 95-97 cam nose, with regard to the relief hole and the dowel pin length.

This article has some good info on the differences in the provisions for the Opti.

 

well thanks for that article. ill have to read the whole thing when i get a chance.

now i have a question for you will i have to modify anything far as the dowel pin goes. i read a small part of that article and saw the meaurements for the dowel pins, but will either on of those dowel work with out modifications. if so which one. by the way this is going a 97z.

sorry its such a dumb question. but please help.

 

no... i bought the whole kit at once. it has everthing comp recommended. and paid alot les for it than 700 bucks.

 

hey here is the cam spec sheet

here it be

 

Ok, maybe i missed something. But why is a solid roller cam asking for 986 springs that are for a hyd roller cam and has only 280lbs open?

 

when you find out let me know. i think ill call comp monday. just to verify. if its wrong ill just sell them and buy different ones.