Thread: setting solid cam valves ??

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guy down the street building a 302 chev and has roller rockers and factory replacement solid cam.
he had it going and took it for a spin and came back popping two cam locks had backed off and rockers right off. couple other loose
took a look at the valve clearance when he had it apart and said way too much .cam stated 24 intake 26 exhaust.
he got the intake off and i asked when did he adjust them. he told me when the piston would be at top dead center. i advised tooo loose as valves will be opening well before that. lifers have to be on bottom of bore when adjusting clearance.
i still think the clearance still seems excessive even at the above specs as the rockers seem really loose at the bottom of the lifter travel.
i have not dealt much with solid cams in cars but clearances shure seem to be a lot even a 24 thou and does this not cause a clatter even when hot?
someone smarter than me please explain excessive clearances on solid cams and why and does this not lead to upper valvetrain and pushrod damage ???

Waht cam does he have? i have a 665 lift on mine and 30ths WHEN HOT and yup they make lots of sound!lol he should have a lock down on them to, they are a pain to set up but when its done then there are on. they set hi for the lift on the cam he should have a card for the cam or tell him to lock it up, It maters hot or cold trust me been there and ran bad

card says cold 24 intake 26 exhaust 475 lift or so was not big numbers am i right to not just place on tdc and set but to set with lifter at bottom of travel???

The clearances are designed in the cam profile, there's a "take-up ramp" that lifts the lifter gently until all the lash is gone. I set solids by finding TDC by split overlap, then setting the valves on the cylinder straight across the dist. cap. That way I'm sure of TDC,compression stroke.

What R Pope said....I set mine at TDC also, but make sure it's on the compression stroke. Set intake and exhaust. Turn the engine 90 degrees and do the next in firing order. Continue till they are all done (two complete revolutions) 24 and 26 is quite a bit, but I have had cams that required that...and yes, they're noisy with that much. Why does your friend have roller rockers but no locking nuts?? You need them for sure.

Roller rockers will drive you crazy with solid lifters. The constant loading/unloading rattles them apart in no time, and the noise is maddening. I know a half a dozen guys I've warned about this, and they went ahead and used them,for a while. Even bought a few sets when they chucked 'em!
BTW, just about every factory engine with roller rockers has a few rollers in the pan, come oil change time!

That's the first time I ever heard that! I have been running roller rockers since '98, and solid cams, flat tappet at first, then solid rollers, since 2000. Never had a problem like the one mentioned. Now, it's not a daily driver, but I do drive the car several times a week and over the weekends about 7 months out of the year. I pull the valve covers each spring to check the rockers and the lash. The rockers have been like new, and I usually dont even have to adjust lash. John

You can adjust half of them at cylinder 1 TDC and the other half at cylinder 6 TDC I believe. Yoy need to check to see if the setting is for warm or cold. They will typically be a couple of mils different.

High quality roller rockers work fine with solid cams. What else would you use?! One could probably find some crappy ones that ain't any good; there seems to be a lot to choose from these days. I can vouch for the Crane gold aluminum and Crower forged stainless.

Good luck, Kitz

you guys are making this way to hard .you adjust one valve when other one is up on full lift this put the the other lifter on the base circle of the cam this one you set the lash on . and not hop a round do one side at a time go over them two times watch when you lock them down this pulls up and can throw it off .002 or so.and so will stud gridles pulll the studs side to side and if you use pollylock the studs tops should be flat this helps them lock better you can cut them flat with a valve grinder on the stem side to face them i do it all the time. on roller rockers they make more noise. i like noise. my roller cams run .024+ lash and have run roller rocker and soild roller cams.I started doing this in the mild 80s .but i did not drive this stuff all the time . a stock gm with rocker ball stamp steel shoe type rockers will last longer and will be much more quiet. i would say the best roller rocker would go south at 30000 maybe longer with oiler in the valve covers this is the way i have done it for many years and works the best for me and will work on any engine

You can adjust half of them at cylinder 1 TDC and the other half at cylinder 6 TDC I believe.

This will only work with a stock or slightly over stock cam. With almost any performance cam, the ramps will start to open or close the valves a bit, too much when using this method.

Pat, I have done them that way too....I just have a preference for the way I discribed. Hey, how have you been? Not much going on lately in the big block forum....that's where I usually hang, and see you. Happy Labor day! John

Originally Posted by 1JohnnyO

This will only work with a stock or slightly over stock cam. With almost any performance cam, the ramps will start to open or close the valves a bit, too much when using this method.

Pat, I have done them that way too....I just have a preference for the way I discribed. Hey, how have you been? Not much going on lately in the big block forum....that's where I usually hang, and see you. Happy Labor day! John

have been working on some big blocks at my shop and a bit burnt out . not to much to post. thanks for the happy labor day. back at you. it was my birthday the 2 so i get a long weekend for it

What say you are putting a solid cam motor together and the clearances state 28 E 26 I, You want to check piston to valve clearance, just to make sure that the valve wont hit the piston.

Using the plasticine impression and knife method:

Would you check this with no valve clearance as you wound the motor over,

or

Would you check it with the valve clearances mentioned above, remember, that on a SBC the rocker ratio is 1.5 to 1.

i hope he was talking runing lash on the cam?? if not he is going to have bad things happen

Originally Posted by pat mccarthy

i hope he was talking runing lash on the cam?? if not he is going to have bad things happen

Eh ??

i think it fits ?you are telling him to check pistons to valve ? i hope that .024E and .026I is not piston to valve that is what i tried to say. i think he wanted to know how to set the lash? on the rockers. the cam looks like a gm #3965754 I488 /509 E 262/273 112 lsa