built350camaro

Ok i have noticed that recentlly one of my valves has been tapping, so i thought t was a rocker arm backing off because they hadn't been adjusted sin the motor was built. So this morning i pulled the valve covers and adjusted he valves, i know u turn them out while hte motor is running until they tap then turn hte until they stop tapping, well i did that on all 18 of them and then the intake valve on #3 cylinder started tapping again so i tighten it some more, but it didn't stop tapping. Also i noticed that that cylinders pushrod wasn't spinning like the rest of them, so i thought o great a bent pushrod. I pulled that pushrod and it was bent (but not bad) so i just replaced all 18 of them to be safe. So i put it all back together and set the valves and that one still taps, and the pushrod still doesn't spin like the rest of them do. So could this be a collapsed lifter or something else wrong? Also when u tighten the valves turn them unti they sop tapping hen how much further?

Sorry for hte length of this post.

RB83L69

Not good. If the push rod doesn't turn, then it's probably because the lifter isn't turning, which means that lobe is probably either rolled off or somewhere in the process of doing so. That's usually the result of either running the engine at too low RPM for its first few minutes of operation; or too little valve springs for the cam; or a block with The Lifter Bore Problem, where the lifters don't point at the cam; or using synthetic oil as break-in lube.

Anywhere from ¼ turn to a full turn past zero lash is OK; about ½ turn centers the lifter plunger in its travel. That's what I consider optimum. Others may have other preferences.

ede

did you replace 2 of them twice or do you have a v9?

uidzer0_z28

lol thats what I am wondering

built350camaro

i meant all 16 of them, don't know what i was thinking at the time. So a lob is going down on the cam then? That pushrod des move back and forth while hte motor is running, like it wan'ts to spin but it doesn't, it jsut rocks back and forth.

flyin89

iTrader: (7)

Yep and if you get someone to turn it over with the coil unhooked you watch the lift compared to the others you'll get a good idea of how far gone it is. Has there been metal showing in the oil before cranking it check,If its not to far gone you may be able to just replace the cam and lifters.

built350camaro

I checked that today and it looks like it has the same lift as the other ones. Could it be the lifter is hung i teh bore by some crud? The cam is about 6 months old so i hope it doesn't have a lobe going down. Could it be a collapsed lifter? If it is the cam how hard is it to change the cam with hte motor in the car? Wat cam would u recommend for my combo? 350 bored 0.30 over, flattop pistons, going to have Pro Topline heads soon, 700r-4 trans with a 2500 stall convertor, and it has to be daily driven.

flyin89

iTrader: (7)

I can't stress enuff how good a deal I think the vortech heads are for 350's. You have that nice overdrive and a big gap at first to second shift you should step up to a 3:73 gears. Now it is possible your lifter COULD rotate and not turn the pushrod in most cases wear at the bottom of the rocker or actual wearout of it is holding it still. I would spec a 268 comp cam keeping the lift below coil bind of the vortecs About ($450 pr at Jegs) get the RPM intake for the vortecs. I ran a 350 .030 over 345np cast pistons,274 extreme cam,vortech heads (machined for the 500 lift),RPM intake and 750 DP in a MCSS with a street fighter TCI converter,350 trans,3:73 gearing and ran 12.2 at 110 MPH in 1/4. Your times will be slower because of the trans and converter. Add a cutout borrow some slicks (youll need them) have fun!

built350camaro

I am trying to stay away from aluminum heads, and Pro Topline makes a great set of 23 degree iron heads that will outflow the vortechs. and the reason i want to stay away from aluminum is that this car will daily see traffic ad i don't want to have to worry about warping a head if it ever does run hot, it hasn't yet, but it might ater i am done with hte mods. What kind of compression would iget from a set of flattop pistons and 64cc chambers?

THANKS for all the help, i love this site

flyin89

iTrader: (7)

Vortec heads are cast iron. you SHOULD get around 10 to 1 comp. I say should because I've seen some H345NP (hyper that are .020 down making about 9 to 1 with a flat top) the 345np cast piston is 10 to 1. Again check out the vortecs closer I think you'll really like them.