Problem with Poston lifters

[tbronk]

I need a little help with my 85 hot air. I overhauled the motor about 15 months ago using a camshaft and lifters from Poston (gn110t & hi rev lifters). About 6 months ago I noticed a tapping noise on cold start from the right bank after the car sat for a few days. The noise would persist for about a minute than go away. I pulled the heads last week to replace 3 teflon valve seals (from Poston new @ overhaul) which had come apart. When I restarted after completing, all was well, untill the car came up to operating temp. Now I have a lifter tappping after the car warms up. Any one have similar problem? It looks like "I'll be going back in" to replace lifters-Who's lifters are you guy's using, type, manufacturer?

One other note, I'm just started running direct scan, my Knock retard is running about 8 degrees at wot, o2's 850s, 15psi boost 44 psi fp could a bad lifter(s) contribute to this?

 

[crazygn]

Irun the comp cams lifters but i think i might have a valve train problem myself. Pop the valve covers and start the car to see if any of them take a long time to pump oil or if they do but very little.

As for the o2's drop that fuel press a little , try 41-42 and start from there. your probabley running rich

 

[tbronk]

good idea-I'll check it out after i return from vacation next week. One other quick question. When i overhauled the motor, I cut in bigger valves 1.77 intakes, checked and corrected installed height and valve stem height. I used the procedure on the gnttype.org website to check my lifter preloads (with the spark plug gapping tool)all was well at rebuild. Is there any other way to check lifter preload after i install new lifters? The other method is a bit tedious.

I was surfing atr's website and found factory (GM) lifters, anyone have luck with these?


thanks for your help!

 

[6SENSE]

I have had more luck with stock type lifters than any others.
My brother's '86 had an ATR cam with ATR lifters and always tapped. We took the lifters out and put in some stock type like I have in mine and all the tapping went away. We were then able to shave a second off his et ! The tapping was loud enough that he was getting lots of (false) knock retard!
My car never has any tapping and the lifters have now been in there with a Poston cam for almost 15,000 miles.

Now the part youre really going to like. Guess where we got these lifters from............ thats right Autozone! (Melling part #JB-969)
You can pay more if you want to but if you research a little, how many companys are there out there that actually make some of these parts and how many do you think just put there name on them? I found out that half of the stock lifters regardless of namebrand or store had almost identical part #s.
Well anyway, they have already proven themselves to me, as far as not being pieces of s$%t ...... and they might even have a lifetime warranty on them too!

 

[REDS HOT AIR]

melling and sealed power are same lifters

sealed power part # is ht969

they are not picky about preload like others are

 

[crazygn]

I have my comp cams lifters out and they look new still , do you think i should just buy some stock ones and try them.They are only like 30.00 my brother just got some him self.

 

[REDS HOT AIR]

yep try some..

get some engine assembly lube from autozone and sqeeze some on the cam and coat the bottom of the new lifters and treat it like a new cam break in.

sealed power or melling #969's like mentioned above

 

[TurboBuickSix]

I have been running the postons lifters for almost 9000 miles in my motor so far and no noise other than the usual after it warms up a bit.I am running the 107 and I like the way the car runs with this cam,lots of torque down low.Did you have the oil passages cleaned in the block,maybe oil is being restricted on that side,or one of the lifter won't spin?

 

[crazygn]

I pulled the comp lifters out today and put the 969 stock ones in so i'll let you know how they work.

 

[crazygn]

It seems to run a little stronger on the top end, but also taps a little , rocker lose maybe.

Reds are the 969's picky with how long the push rods are , my good pushrods are about a 1/8" longer then the stocks that are in it now.

 

[REDS HOT AIR]

mine are preloaded pretty heavy since switching to steel shim gasket which is .042 thinner than stock and mine seem to be ok.

if they are that loose probly wouldnt hurt to try em.