breakthelawinaz

i just finished re-building my 427 L88. i had about 100 miles on it and noticed a tick in it, so i pulled the valve covers and there was like a 1/2 to 3/4 in of slop in the rocker so i investigated more and it turns out the lifter was wore doen about a half inch and the cam lobe was almost completely gone. here are my engine specs.
-L88 block, crank, & rods
-forged 14:1 pistons
-balanced to .3 grams
-fluidamper
-L88 oil pump, blueprinted with anit-cavitation grooves
-moroso windage tray
-arp main studs
-clevite 77 tri-metal bearings throughout
-oil restrictors .060 orifice
-cloyes true roller timing chain
-schneider custom grind solid cam and lifters
-manley pushrods
-cam thrust button
-comp guideplates
-manley swirl polished 2.19 1.88 valves
-fully ported and polished L88 heads
-port matched edelbrock intake
-holley double pumper
-fel-pro gaskets
and there are other things i probally forgot....

anyways when i assembeled it everything is within specifications including cam endplay at .011" and valve lash at cam grinders specs of .020" cold. the car always had good oil pressure and i broke it in by the book, 2000-3000 rpm for 20 minutes and my idle is about 1100-1200 rpm and the oil pressure is never below 40PSI.

the engine builder i got all my parts from and did all my machine work said he had some problems with big blocks and oil restrictors, he said they sometimes develop air pockets his solution is to drill a .030" hole in the plugs at the front of the block behind the timing chain above the cam, but i dont want to be in this situation again so what do you guys think? should i remove the oil restrictors? or redrill them to like a .080" i ran the restrictors because i have a solid lifter cam and full roller rockers so i thought that would free up some horse power. he also seemed to think i had a binging valve but i know for a fact i dont i just checked them all and everything is good.

i have all the replacement parts on the way they will be here tomorrow and hopefully i will have it in the car and ready to go on saturday but first i need to kbnow what caused this problem. thanks, and if you need anymore information ill be more than glad to give you more info.

*eric*

Lonnie Pavtis

Being that you have a solid flat tappet cam, they are very sensitive to break-in.... especially with the corresponding stiff springs. Many people break in the engine with only the outer springs to be easier on the cam. This is a pain to do as it requires on the car spring work.

Also be sure that each lifter is free to rotate (spin ) in their bores. A small rough spot on the lifter bore can wipe out the cam. They must rotate to prevent flat spotting the lifter.

I also recommend that you should "NOT" put assembly lube on the sides of the lifters (use oil only).... thick lube can impede their rotation & ruin the cam on initial start-up.
I recommend the moly paste instead of the thick "STP" type of assembly lube (on the lobes & lifter bottoms only) as it stays on better. Just change oil immediately after break-in.

Keep rpm above 2000 for 20min as you stated.

The .030 vent in the end plug is fine & should not require more.
I do not recommend oil restrictors in any motor unless it has a roller cam in it.

Straight weight oil is also recommended (40HD) instead of multi viscosity for initial break-in.

Hope this helps.

Steve in Seattle

• How much spring pressure do you have?
• How much cam lift?
• What type of lifters are you running?
• Was is just ONE lifter that had this problem?

The 40 psi may be deceptive BTW, as oil pressure readings vary from engine to engine, but usually get a reading from right after the pump before the restrictors.

The 10psi/1000 rpms rule of thumb typically applies to pressure at the bearings from what Ive been told. Restrictors might be causing you to "see" significantly more pressure than you're actually getting at the bearings. I've never run them, but that's the way it was explained to me once. Hopefully someone here will be familiar with restrictors enough to give you a better guideline.

Steve in Seattle

looks like I didn't type fast enough. Good info Lonnie.

tanmanski

I'd suggest cutting your oil filter open & taking a hard look at what's in there, maybe even get a spectrometer oil analysis done - it's cheap just takes a little time. Reason I say this is I had a smilar experience with cam lobes & lifters getting wiped out, although I had bearing damage also. Have you looked at your cam & crank bearings yet? Anytime you generate as much debris inside the engine as yours probably has I'd wanna see those bearings before I put it back together. Turned out the shop that did my machine work had failed to properly clean out the oil galleries in the block & my oil system was contaminated with bead blast media...which will show up as silicates in an oil analysis...it wasnt a major hipo engine like your is tho, so this info may not be relevant...just offering up a thought on getting more info on what did ir did not happen to your engine.
good luck,
Ian

12Second3rdgen

Had a similar problem in a small block chevy, cam went flat just after break-in (a proper break in as well). Turned out the comp lifters werent spinning in the lifter bores. Swapped them out for the used GMPP lifters, spun like crazy. Put the brand new comps back in, different lifters in different bores werent spinning, and it was random it wasnt just certain lifters or certain lifter bores. Wound up reusing the GMPP lifters since they had a thousand miles on them and still had a good crown to them.

1racerdude

I don't put any restrictor's in any street engine,period.You do not get the splash lube required for the cam and lifters. The pin hole is OK in the front plugs as long as it is not over .015-.020 you are just bleading air from the oil galley and a small amount of lube for the chain.
You didn't say what your spring pressure was ,but if it is much over 140-150LBS on the seat I would soft spring it for a few miles and then put the rest of the load on it. Unless of course you want to keep buying cam's and lifters.Ask your cam maker what their procedure is.

breakthelawinaz

spring seat pressure is between 127-130psi, and the lifters felt very good in the bores, they were pretty free to rotate, the cam lube i used was crane cams lube kit which consisted of the cam paste and the concentrate that you also add to the oil. i used castrol 10w30 for break in and drained it immediately after break in, (basically as soon as i shut the engine off i jumped out and pulled the drain plug out) i also cut the filter and checked it, everything was very good.

the block was hot tanked, everything else was spotless. the cam lift is right around .600 im not 100% on it, (i dont remeber the cam specs off the top of my head) i think its actually like .592 or something odd like that. the lifters were the solid lifters that schneider supplied with the cam i beleive they are a GM factory lifter, like that came in the L88s and LS6s.

i had one lifter that wore through completely, there was a hole in the middle and it was tapered, but the way it wore made it look like it had very good rotation. all the lifters looked like they had good rotation. two other lifers started to mushroom over also but they were all on the pass. side of the car. thats what makes me beleive it was a lack of oil.

the engine builder i talked to said that big blocks have problems with oil sometimes wehre it will sometimes not send full oil pressure to the passenger side galley and be rediverted down the distributor shaft. i think im just going to take the oil restrictors and toss them in the trash right next to the cam, lifters, bearings and everything else they ruined... and just run the stock plugs. i am also goign to drill some pressure relief holes in the front plugs. i should get it back together this weekend, ill let you know how it goes.

i heard there was some power to gain running oil restrictors but after driving the car i could stand to lose a horsepower or 2, the car is almost un-drivable on street tires and 14's. only one time that i had it out did i even realy get into it and it would spin coming off the line then i would get it to stop at about 3000 then at about 4000-4500 it would break the tires loose again, its just too much power for those little tires and is going to take a little bit for me to get used to, especially in a 3300 lb. car. i just dont trust them. ive also heard the not running them will hurt an engine because it gets too much oil but i beleive that about as much as i beleive in the easter bunny if you get what im saying. thanks hopefully some of the info i supplied might help you help me.

EDIT: btw the bearings actually look very good, there isnt a sign of grit in any of them, i was very suprised, i havnt had time to cut this filter up but i hope its full because then i know my filtration system is working good. im still replacing all bearings but by the looks of these i wouldnt be afraid to run it again with these ones. the oil is also clean, there is very little grit in it. the oil is still light in clolr and there isnt much for metal shavings, no more than usual in a new motor that has new rings and what not. i cant beleive that the cam is bad, if i didnt knowthat the cam was bad adn i just drained the oil and looked at it you would swear there wasnt anything wrong, maybe i might get lucky and nothing else is damaged, but like i said im replacing everything anyways just to be safe. i dont want to be back here in 2 weeks again! again thanks for the help!

*Eric*

1racerdude

The main reason for oil restrictors is to not put enough oil up top to drown the valve seals,and keep more oil in the pan for the rest of the engine.If you don't have a trailer queen you shouldn't run them.I don't feel that there is any HP gain on a street engine.If you drown the valve seals you can suck oil in the intake valve stem and cause detonation in some cases and make for an oil burning engine.Todays seals and smoothing the drainback holes will take care of it.
GL and check with your cam grinder about break in because you are pretty close to a soft springing break in.Follow their instructions to the letter and you will be OK. GL

breakthelawinaz

yeah, i have definately decided to trash those stupid oil restrictors. i had the head machined for the newer style viton valve seals like what is used in the LT1s i beleive so i dont think this will be much of a problem with too much oil. i smoothed all drain back holes laso and i think im getting plenty of oil drainback. my new cam is a comp magumn 294S i beleive is the grind #. should i maybe increase my lash during break in a couple thousanths too or just take out the inner spring?
thanks

EDIT: also you prefer a straight 40 weight high detergent oil? ill try that this time, hopefully i will not have to do this again, i thought buying one cam was good enough but i guess not... my engine aparently didnt like this one!

*Eric*

1racerdude

Sounds like a good cam selection. Personally I use a streight 20W on break in for about 500 miles and then change to whatever you like. Again I would follow Comp's instructions on break in. It would be worth a phone call to get it streight from the horse's mouth.

breakthelawinaz

yeah i prolly will do that, so is it more then likely that the oil restrictors were the cause of my engines destruction then? i thats about all i can think of because all the signs seem to point toward that. i broke it in to specs, correct lash, no binding valves, lifters were all rotating, cam endplay was correct, pre-lubed before break in, and the fact that everything happened to the passenger side. im assuming that is the problem and im going to reassemble the engine and hopefully that never happens again.

BTW: any big block guys-have you ever forgot to put the plug in the oil galley on the driver side on the engine just below the timing cover. i thought it was an accessory mount and i went to pre-lube my engine and i wondered why it wasnt building pressure, then i looked down to see 6 brand new quarts of oil running down the drain... needless to say when i forgot that i wondered if there was anything else i forgot, thats why im really paranoid now that this happened. thanks

*Eric*

Lonnie Pavtis

First if you are running this as a street engine, forget the oil restrictors. My big block lives happily without them at 7600rpm.

What distributor are you running & where is it phased in relation to the intake. There is an oil passage in the distributor body that may prevent oil to part of the oil system if it is rotated too far from the proper location. Some distributors have the oil slot all the way around them & some do not.

Also what year engine is it? The early big blocks require a grooved rear cam journal.... I think this was '66 & prior only. My '65 427 requires the grooved cam journal. Without this, oil does not get to the lifters.

Hope this helps.

Damon

You might want to do a search on my screen name in this forum and also over on nastyz28.com from about a month ago.

I had a solid cam and lifter set go down on my shortly after break-in. The first time this has happened to me. I've done LOTS of cam swaps/break-ins in the last 20 years of going fast as a hobby. Like you, I am **** about assembly and proper break in. Killed it anyway.

Long story short- it won't make you feel much better what I found- the cam and lifters were not properly hardened and were doomed before the engine ever fired up the first time. But it might be worth a read anyway before you pull big clumps of hair out of your head. Beleive me- been there, done that. Definitely leaves you with a kinda "hollow empty" feeling in your gut, but you may well have done nothign wrong- coulda just been bad parts.

I checked every conceivable thing that I could have done wrong. I did nothing wrong (go on- check the threads for all the gory details). The happy ending was that with a fresh cam and lifter set it didn't happen the second time.

breakthelawinaz

Lonnie- distributor accel billet electronic, i beleive it has the groove all the way around, thats what the engine builder i talked to asked also and i beleive it is good, actually its the same distributor that was in it before it was tore down without problems. the block is a 1969 L88 block. 7600 is about where i want mine at too.

Damon- im going to do the search in a minute, i have questioned the parts quality also, that is why im getting my cam and lifters rockwell tested and i get the results today around lunch time. hollow empty feeling dosent even begin to describe it, but it makes me feel better that people are in the same situation. did you end up doing an entire tear down and doing it al over again like i am doing or did you just clean it up and slide the new cam and lifters in?

thanks guys!

*Eric*