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i am i8 years old and i am rebuilding a 327 and its my first. i want around 300hp and i was wondering if i should put roller rokers on? Whats the differance between a solid cam or roller cam and which one is better? there is a gear drive for the timing and its says noisy and i was wondering if its a loud blower sound or what it sounds like or if i should use it? so if theres any tips on things to help me out let me know. i want that first time to be a special one.
 

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Roller rockers are rockers which have a roller on the tip which slides back and forth on the valve stem. They have a pair of discs on the side that center them over the valve stem and eliminate the need for guide plates. I have heard that they are a little more efficient than using guide plates. They are standard on newer LT and Vortec headed engines like the ZZ crate engines.

Roller cams are race only. They won't last for street use very well and will wear out in less than 20,000 miles. They will allow for steeper lobe ramp angles and therefore can open valves sooner and carry open time longer. They can make huge power.

The gear drives are noisy as hell. They do sound like an old 6-71 blower. But they are in my mind not appropriate for a street car. You can hardly carry a conversation over the sound they make. But if you want to be distinctive to the local cops, they will absolutely get you attention.
 

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Well, not all roller rockers have discs on the sides, so be careful what you buy, many of them you still have to use guideplates and if you dont use guideplates on roller rockers with no disks, you can kiss your valvetrain goodbye. So make sure you know what you're getting. Also, there are 4 different kinds of lifers: solid flat tappet, hydraulic flat tappet, solid roller tappet, and hydraulic roller tappet. If its a street car, and only sees minor track time, use a hydrualic lifter. Solid lifters are race only, wether you use flat tappet or roller. Now, as for hydrualic lifters, every street engine has them and they are extremely reliable. Older V8 engines usually from the 80's and earlier have flat tappet hydraulic lifters. These work fine, some people prefer them. ALL 5.0s from 85 and up and LT-1, LS-1, and LS-6 motors came factory equipped with hydraulic roller lifters. The benifit to these, is that is has the same street behavior as a hydrualic flat tappet, but offers less friction becuase of the rolling movement over the lobe, making for longer valvetrain life.

Also take this comparison into consideration. You have one F.T. camshaft and lifters, and one R.T. camshaft and lifers with the exact same specs. The R.T. camshaft and lifters will make more power because of less fricion and, becusae of the roller tappet, the ramps are allowed to be more steep on the lobes making for a faster opening valve.

Also, you must know this. Roller camshafts can only be used with roller lifters. Flat tappet camshafts can only be used with flat tappet lifters. THERE IS A DIFFERENCE! And, i dont know about chevy, but for fords, you need a roller cam specific block. If you dont have one, you need to get the lifter bores machined to accept one. Once you have it machined to accept a roller cam and lifters you can always go back to flat tappet if you want without doing any changes.

I changed my engine to hydraulic roller tappet and it works fine. Just think, there are plenty of 5.0 mustangs out there with these cams that are going 150,000+ miles with no trouble. So needless to say, i would recommend the hydraulic roller lifters and cam.
 

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I have heard only one gear drive in my life and I remember walking around the front of the car and saying, "what in the hell is that noise?"...I thought something was wrong with the car because no engine should wine like that. That was my only experience with gear drives but that noise would drive me crazy.
 
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