Rocker shaft pedestals

[rw87tt]

I will be installing a Comp. Cam 206/210 Roller cam with the .516 lift and bee hive springs. Is that too much lift to use the stock rockers? Do the rocker shaft pedestals have to be machined at a machine shop for roller rocker instalation? How much is machined off for side clearance if installing the T&D or the H/S rocker? Any feed back would be great. Thanks

[turbofabricator]

Stock rockers "can" work. I feel that the roller cams NEEDS a roller rocker system. With .516" lift, you will have retainer to guide issues on the exhaust side, though. If you trim the exhaust guide for cleraance, you will need to install a good seal (i.e. PC seal) BUT they will NOT work on a stock exhaust valve. PERIOD!!! With stock heads, the roller cam is just barely doable. I don't like that much lift with stock stuff. It works for some people, but I am concerned about retainer to guide clearance. Trimming the rocker pedistal is pretty easy off the car. On the car, it can be done, but it is "iffy" You need to grind the side of the pedistal to gain clearance on any of the roller rocker out there. When I port a set of heads, I always do this mod. I never know if they are going to use rollers in the future or not. It only takes about 10minutes when they are on the "bench". Do a search on this topic and there are lots of pics already posted.

[rw87tt]

Turbofabricator. Thanks for the good info. I guess one of my questions was wether I could trim the sides of the pedestals myself with a grinder or find another means to do it more accurately. Since my heads are at the machine shop I might have them do it. I would like to know how much to mill or grind off the side of the pedestal to install the H/S or T/D rockers from the center of the shaft mounting bolt hole. That way I can tell the machine shop how much to mill off. They are suppose to cut down the valve guides to install the valve seals.(viton) on both intake and exhaust.(both valves are stainless) I was not sure if I was going with the rollers or not. I think I'm going to bite the bullit and go with rollers. I had planed to do some mild porting myself on the heads. That pt 6162 might have to wait for a little while. I was really going to go with a 206/206 roller cam with a lift below .5.When I talked to the vendor he convinced me to go with the cam I currently have. I hope it was't a mistake. I was planning to use a 2800 stall converter. Any suggustions on what rocker arms? Thanks

[turbofabricator]

You can do the trimming yourself with a die grinder and 1/2"-3/4" stone. That is what I use. Trim about .150" off the sides about .250" lower. It will only take you about 10 minutes to do the entire job. Have fun porting your heads. It is a real dirty job, so wear a respirator and have a vacuum running the whole time. Also wear hearing protection and face shield. You will need about a good electric die grinder (Makita makes a real nice hand held one) and about $200 worth of carbide burrs, sanding cones, extended length mounted stones, either a router controller or you can use a household dimmer switch to control grinder RPM. High RPM (20k) for the carbide and stones, and 10k (guesssing here) for sanding rolls. Play around with rpm and tool pressure to get a feel for what works best. Your hands will be numb after the first 6 hours of grinding. Better do some grip strength training before you start porting. It takes ALOT of forearm strength for good tool control. Cut down your 6" carbide to about 4 1/2". If you leave it at 6" with out good muscle memory and forearm strength, you can do some REAL damage to your heads and yourself if you let the 6" burr get away from you and chatter and bend. It'll RIP the grinder right out of your hands if you are tired and weak. Do NOT use a Craftsman die grinder. They have very poor chucks and it will not hold a long shank burr true. You "can" use air grinders, but they consume ALOT of air and electricity to run a BIG compressor. They also get VERY cold in your hands as you grind. Not a good combo for good tool control.

[rw87tt]

What! 200 dollars worth of carbide burrs! I was thinking more like 45 dollars worth of E/B specials including shipping. Turbofabricator, I found your post on the head porting stuff. It is some great info. I was going to concentrate mostly on the exhaust side but I am kind of leary about grinding most of the exhaust guide down. It sounds like Head porting involves consumming mass quantities of beer.

[Blown&Injected]

it is a good idea to get some junk heads to work on before cutting on your good heads

[rw87tt]

Thanks for the feed back guys. I will find me an old head and see what head porting involves.