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mine kept backing off on my old 355, I ended up just buying a box of nuts from the hardware store and adding a jamb nut to the tops of all the studs. Never had a problem again.
What kind of rockers are you using? Using stock pressed-in studs? Screw-in studs? With stock rockers + studs, theres enough room for jamb nuts. Unless the threads on the stock studs are really worn, a new set of stock rocker nuts from GM, comp cams, or similar shouldn't need threadlock. With all the oil, the threadlock is nearly useless there, anyway.
There is not enough space for a jamb nut.
I thing about try to use "liquid metal"
dont use that or anything like it. you wont be able to readjust your valves later if you need to.
you could try nylon lock nuts or a set of posi locks for roller rockers
what i would do if i was you is pull your heads off and have the studs replaced because that is were your problem would be if you got new lock nuts and they back off.
What holds the torque on stock nuts is the oblong shape (as opposed to round) at the top area of the nuts.
After several tightening/loosening/re-tightening the oblong shape gets rounded out. After that happens they can loosen. If that's what's happening a new set of nuts will solve your problem. They're inexpensive and available at most auto parts stores.
However, press-in studs are known to begin to get pulled out over time, especially when higher pressure springs are installed and/or repeated high RPMs are used. GM probably moved away from press-in studs for that reason.
If that's is happening, the heads should be pulled. The least expensive fix is to have a machine shop pin the studs. Best way, though, is to have the stock studs pulled and the stud holes tapped for screw in studs.
Tapping has been done with the heads installed on the block, but there'll be a lot of shavings to be concerned about. I don't recommend doing them that way.
Jake
__________________ My son, Ryan M. Cameron, graduated from West Point on 22 May 2010! He was commissioned as a 2nd Lieutenant and I pinned on his first pair of "Butter Bars" PROUDEST DAY OF MY LIFE!!
What kind of rockers are you using? Using stock pressed-in studs? Screw-in studs?
Stamped steel with roller tip rockers. studs are stock pressed in.
heads are resurfaced and shaved down by 0.7mm to rise up compression. therefore there is no space for jamb nut.
Quote:
you could try nylon lock nuts or a set of posi locks for roller rockers
I think nylon is not the best locking material for high temperatures.
Quote:
However, press-in studs are known to begin to get pulled out over time, especially when higher pressure springs are installed and/or repeated high RPMs are used. GM probably moved away from press-in studs for that reason.
Yes, I have stronger springs because of cam change. and my engine quite often sees high revs, however there is no problem with studs.
will try to use new nuts and "lock tight"
thanks for your replays..
No.
What would be the reason doing so? this will increase installed height reducing spring pressure . which will result in valve float... I use quite aggressive comp's 08-412-8 camshaft.
the comp cams specs on that says that head machining required. You would of had to machine the spring pockets to have the correct installed height probably. Did you measure the installed height of your springs??? That's more lift than ususally is good on stock heads.....495 lift is what I found. What is your installed height, and what does your springs call for??
__________________ "Wide open 'till you see GOD, then brake!!"
'91 Camaro RS B4C Police Special Service Package
350 4-bolt, 10:0 w/moly rings, Holley Stealth Ram (ported), BBK 58mm, MSD ignition, Procomp heads 2.02 1.60 200cc (63hrs. port work), 30# venom injectors, Flowtech headers, full custom 3.5" mandrell ceramic exhaust w/ aerochamber, Comp cam XFI280HR (.576/.571 234/244), PCMforLESS.com tune, 58mm BBK, Custom TPI air lid, Custom RamAir, 1.6 stainless steel rollers, Custom 700-r4 2500 stall, Aluminum Drive line, 3.23 posi, Moser axles w/stud girdle cover, Spring works springs (lowered), UMI relocation brackets, panhard, LCAs, sub-frame connector, boxed A-arms, Poly bushings, Custom interior, Powdercoated & polished IROC wheels, Custom "Black Cherry" Paint", 4pt. roll bar, +++ more! "It's not the tires squealing, it the asphault SCREAMING!!"
the only thing i did to accept gross valve lift I trimmed valve guide a little so there is 1mm space between retainer keeper and valve guide at max lift.
Springs where the same as stock except stiffness.
There is no problem with valves, or rocker geometry, or any related ... the only problem is rocker nuts.
I think JakeJr might be onto something suggesting the studs might be pulling out. Put a straight edge along the tops of the studs and see if any don't touch the straight edge, then you'll know.
91interceptorZ is also correct in saying that shaving the heads will have zero effect on the studs. If you're using stock replacement nuts there should be more than enough room for a jam nut on top of the rocker nut.
the only thing i did to accept gross valve lift I trimmed valve guide a little so there is 1mm space between retainer keeper and valve guide at max lift.
Springs where the same as stock except stiffness.
There is no problem with valves, or rocker geometry, or any related ... the only problem is rocker nuts.
I certainly hope you're right because if you're not . . . . .
you do need to measure the installed height of the spring and such.....there should be no fitment issues. Checking the studs as well is a good idea, they might be pulling out.... Something is NOT right, it for sure should not be like this. Something is not measured correctly, or coming apart. Need to figure out before it damages something badly. good luck.
__________________ "Wide open 'till you see GOD, then brake!!"
'91 Camaro RS B4C Police Special Service Package
350 4-bolt, 10:0 w/moly rings, Holley Stealth Ram (ported), BBK 58mm, MSD ignition, Procomp heads 2.02 1.60 200cc (63hrs. port work), 30# venom injectors, Flowtech headers, full custom 3.5" mandrell ceramic exhaust w/ aerochamber, Comp cam XFI280HR (.576/.571 234/244), PCMforLESS.com tune, 58mm BBK, Custom TPI air lid, Custom RamAir, 1.6 stainless steel rollers, Custom 700-r4 2500 stall, Aluminum Drive line, 3.23 posi, Moser axles w/stud girdle cover, Spring works springs (lowered), UMI relocation brackets, panhard, LCAs, sub-frame connector, boxed A-arms, Poly bushings, Custom interior, Powdercoated & polished IROC wheels, Custom "Black Cherry" Paint", 4pt. roll bar, +++ more! "It's not the tires squealing, it the asphault SCREAMING!!"