took car to the track, ran a 13.5 in the 1/4 with NOOOO traction, my 2.2 60' are evidence that the 225/60/R16 bald crown vic tires arent up to my motors needs, ended up with a best of 13.5 at 110mph.

heres the issue on my 7th run (the one i ran a 13.5 with) motor ended up dying on me at 5000rpms at 110mph about 3/4 way down the track, smoke out the exhaust.

pulled into the pits and found a broken rocker stud on the #5 intake. got the car home and noticed that the lifters insides were completely gone! pulled the intake and found the lifter peices all in the lifter valley. later inspection showed that the cam lobe is slightly scored on that lobe where the lifter failed.

now idk whats causing this, motor only has 350miles on it. cam is XFI280, 230/236 .576/.571 lift. using correct length comp cams high energy pushrods(wear line is dead center of valve stem) using 1.6 full roller proform rockers and the patriot heads have valve spring upgrade good for .720 lift. so basically idk whats goin on with this thing. i clearance the stroker rods myself for about .050 clearance to the cam. and i shouldnt have to worry about the rods hitting the cam on the #5 cylinder. I called comp cams and the guy didnt seem eager to help me, he said the #2 and #6 rods are the ones you have to worry about. but the cam scores look like little U shaped groves.

any ideas? snapped rocker stud, destroyed lifter(lifter insides in valley), scored cam lobe (not from lifter)... this is the second time ive snapped a rocker stud in the cars 300mile life span

 

Thats kind of a loaded question.

Since just about everything you have is not stock, you might want to check things for yourself if you havent already. Check the piston to valve clearance, check the stem pattern again, the rocker arm alignment, wear marks on the pushrods and other rocker arm studs, and definitely verify if you really have .720 of space for valve opening. That right there sounds suspect to me, I would check both the lift the assembly will allow and also how much the spring allows before coil bind.

That cam is going to need the right valve springs to work right. The ramp rates are very quick, and you will need the right closed and open pressure to keep the valves under control. You did not list the spec for that, its a possibility that the springs are not adequate as installed to keep things from flying apart.

 

i honestly doubt i have any piston to valve clearance issues. the pistons are SRP forged dish -16cc pistons. but it might be a good time to pull a head off and check it to be sure.

i just pulled the rockers off and u can see the wear mark on the valve stems... its maybe 1/8" thick and is dead center of the valve stem.

not sure i understand what you mean by rocker arm alighnment. but they seem to face outward (they are self alighning proforms) and no im not using guideplates but i cut the guideplates and used them as spacers bc you cant tq rocker arm studs to bare aluminum head or you'll score them.

something i have noticed is a wear mark on the tips of all the pushrods... the ball tip that fits into the cup of the rocker arm. seems the rockers have wore a ring groove into the ball cup of every pushrod.

I kno about the head specs bc I was just on the phone with skips white performance where i got the patriot heads... i got the roller cam spring upgrade which used dual springs good for .720" lift, and thats what the guy told me. i could perhaps check the springs. comp cams recomends there springs for the cam (they always do) heres the cam specs http://www.compcams.com/Cam_Specs/Ca...?csid=209&sb=0
they ask for the 26918-16 springs. seen here http://www.compperformancegroupstore...Category_Code=

i cant seem to find the info on the heads on skips white anymore. they say the patriot heads have been discontinued and they now offer the procomps as the same as the patriots. believe they are either 1.55" or 1.46" valve springs, dual springs, with stainless valves, they are .100" longer on the intake i believe

 

I'd say you might want to check your installed height on the valve springs, that much wear and breakage could be an indication of coil bind....What is the open and closed pressure of the valve springs you're running at their current installed height???? Also, are the rocker studs ARP's or just some imported pieces that came with the heads???? Are the valve guides to tight??? What you have described sounds like mistakes have been made in setting up the valve train.....

 

Either something's binding (rocker arms reaching limit of travel, springs coil-binding or retainers hitting the tops of the guides) or you have weak rocker studs. Aftermarket heads sometimes come from the manufacturer as a "bad batch" They just break eventually.

Another thing that can happen is if the poly-lock is gorilla-tight. Combine that with perhaps a bad batch of studs and you'll snap them right at the bottom of the poly lock eventually every time.

Lastly, the poly-lock has to be able to grab enough threads on the stud. If it's only grabbing 4-5 threads at the top of the stud you'll eventually stress and break the stud as well. Again, right at the bottom of the poly-lock. You want to grab a good amount of that stud- like about 1/2" of threads or so. The fix for this problem is obvious- longer studs.

Also, you should consider using larger 7/16" studs in any higher performance small block- especially with aggressive roller cams or any solid tappet cam. I almost always use bigger 7/16" studs, but that means rocker arms to match, which is added expense if you already own rockers designed for smaller 3/8" studs.

 

im not exactly sure about the coil bind etc... they were setup at skips white but the guy said max lift with these springs are .720". i dnt exactly have the tools to test coil bind. which is why i had it set up for me. I also dnt have the specs on the spring pressures... they are all from skips white (thats prob the only info on this motor i dnt know lol)

the rocker studs where the ones they sent with the heads... originally they snapped and it was one they sent out first and seemed cheap, so i had them send a whole new set which they claimed they where milodan or moroso or something... and now i get this. (altho the studs look the same to me).

this seems to be exactly what is happening. the 2 studs that snapped both broke right off at the bottom of the adjusting nut. they say 3/8" thread must be used on the rocker stud if your running 3/8" studs. and it has about that, but still snaps right below the rocker nut. and i am tightening the poly locks "gorilla" tight lol. thats what i was told to do, i get a nice loud pop when i break them loose and i get scared i broke something.

Im not gona mess around and im gona have to get the ARPs. I measured the height of the studs im using now and the studs that ARP sells and they seem to be within .100 or .010 of an inch of each other in length. this still doesnt explain why my lifter exploded and why my cam lobe has U grooves in the lobe... i'll post pics of the cam lobe later if i can get some pics of it . def not upgrading the studs to 7/16" i should be fine with the 3/8" and i cant afford new rockers... esp in the cam took a dump on me.

 

Any possibility the lifter got turned sidewise to the cam lobe while it was doing it's "exploding" thing? Grinding the edge of the roller into the lobe instead of the roller rolling smoothly over it.

Lifters shouldn't really blow apart like that, I agree.

One other thought I had.... 650 lift clearance and springs that are good for 720. Both of those are pretty big numbers. And they may well be true. But IF they are true I wonder how much "overkill" the springs really are for a "street" cam like you're using. A spring that's built for that much lift is typically going to give a lot more pressure than the usual 150 seat/350 open pressures a cam like that would call for. Knowing the specs on the springs would be nice. Maybe they're just way more pressure than you need, putting a lot more stress on the whole valvetrain and contributing to some of the issues you're having.

No need for gorilla tight on the poly locks. Snug will do if you do it the right way. That would be setting the lash, tighten the lock snug and then snug the whole thing down a little further by turning the allen key and the wrench tighter together a small fraction of a turn. A "feel" thing mostly.

 

With high pressure springs and big valve openings, a stud girdle will also help to add some strength and control some of the deflection on the rocker arm studs....

 

.050 from rod to cam clearance? you know things tend to stretch when there turning 6000 rpm lol

 

yea i was on the phone with skips white last nite, its def not a good day yesterday lol. He said that the .040 thousands would have been fine with cam to rod clearance since thats the minimum that "he would do" but its pretty standard for most ppl. he says he likes to clearance them for about .060-.080". he said that if u have .040" clearance and your rod hits the cam then u got bigger issues since there is like .015"-.020" bearing clearances it still shouldnt smack it esp since im using ARP hardware.

Ty_rich... thats what i figured but see i wasnt turning 6000rpms i mite have done 5500 one pass lol but still charlie from skips white said even with .040 clearance if the rod kit the cam than u got bigger issues than that with the bottom end. I dnt think the rod bolts being ARP cap screws will stretch .040".

THis is what i was told! he bets that the issue with the studs is the lifters. Ive been using stock replacements (speed pro/federal mogul) HT-2148. they are stock replacements since i didnt want to stick the 130,000 old ones back in. Charlie said that they used these for a few yrs but had alot of lifter failures and broken studs etc, they switched to a Eaton brand made lifter same partnumber but is made here and is the same company that makes the lifters for compcams etc. the speed pros a few yrs ago started being made in india or something and they wouldnt pump up, this would cause loud valve train noise (which i had), worn pushrod ball tips(which i have), and slop in the lifter after being run (which i had). this would lead to broken studs if the pushrod jumps out of the lifter and catched the edge (it would be solid then) and would push up on the rocker and snap the stud. Also a lifter that wouldnt pump up would also cause slapping against the rocker (where pushrod tip craddle at back of rocker where its seated) and would wear a sharp groove in the pushrod ( i have that) and would basically slap the rocker every rotation. this is like hitting the rocker and rocker stud with a hammer, which will fatigue it until it snaps below the rocker arm nut (which it did on both studs that snapped). Also tends to wear the rocker studs where the rocker sits around the stud (u can see this on my studsm the threads are worn over).

Soooo in the end... SPEED PRO LIFTERS SUCK! and i will have to replace them with the eaton ones. sold here http://www.skipwhiteperformance.com/...x?Item=HT-2148

But i did get the specs on the heads. here they are
1.)the rocker studs they sent where manely studs.
2.) head springs are 1.46" DIA and dual springs.
3.) springs are good for .720" lift
4.) springs have seat pressure of 125-132lb
5.) springs have fully open seat pressure of 375-385lb at .700" lift. at .550" lift i should be around 358lb, thats what he tested.
6.) for the 1.46" .720" lift dual springs they use .200" longer that stock valves. which requires .100" longer than stock OE roller cam pushrods. (which i have comp cams high energy hardened ones)

now this is my consensus... the rod bolt smacked the cam lobe at like 5500rpms, im in the process of pulling the motor and will have to pull the cam look at it and maybe buy a new one and i will clearance the RODS even more! UGH! the lifters im gona $hit all over them and buy the eatons i guess and im gona bet they are the cause of my valve train issues. sry for the long post but wanted to get it all out there.

what u guys think? should i got .060-.080" clearance on the rods to cam? what do you guys recomend? i had to grind alot to get the .040-.050" that i have on it now.

 

Proform rockers? Those are aluminum, right?

Call Tennessee and ask about CrMo rockers.

http://www.youtube.com/watch?v=DxROQ...layer_embedded

 

yes, extruded aluminum, self aligning. i wouldnt think the rocker would snap like that, i would have to think it was adjusted wrong. theyve been on the motor and all are fine, if anything i keep on breaking rocker studs. that would mean the aluminum are stronger than the studs lol. if they break ill replace them but until then they are working fine.

 

heres some pics of the ruined cam. one was done by a rod bolt im guessing due to the curved imprints on the #6 cylinder(1st pic). the other one is the #5 cylinder (2nd pic) and is the lobe next to the lifter that failed. this is the lobe with the lifter that the edges where rolled over kinda. the cam is ruined to this bad SPEED PRO lifter! AUGh! the rod bolt knicks would have been able to be smoothed out.

so DONT BUY SPEED PRO federal mogul lifters!

 

Aluminum does not have infinite fatigue strength like steel does. This means, that given long enough, it will eventually break and that the life of the rocker comes down to how well it was engineered. If the stresses are high, the rocker will break in short order if its alum.

 

i understand about the rockers.... but no way i can afford them right now. I will prob upgrade them down the road. but for now they are working fine, its the studs, lifters/cam im having issues with now.

so heres an update....

took the engine apart and clearanced the #6 and #5 rods for more room, my guess about the rod bolt hitting the cam was correct on the #6 cylinder intake lobe. when pulling the engine apart i thought hard about the rod bolt and i dnt remember exactly but im pretty sure i screwed up(swapped the bolts) the bolts. The matched/clearanced rod bolt was on the wrong side of the rod. so thats where the grooves are from (see pic) basically the rod was clearanced but the rod bolt wasnt now. I now clearanced the rod/bolt even more now and i tested it. i now have .068 clearance as a minimum on both the #5 and #6 lobes. I then pulled apart the #1 and #2 cylinders and found that they were also clearanced for .068 minimum...

my guestimate with why i figured i had only .050" clearance was bc I didnt have the cam and timing chain set up, i basically just spun the cam and slowly rotated the crank to get the clearances i had originally. this time i left the cam/timing chain assembled. so i have a minimum of .068" clearance... im hoping this is enough.

other pics are of the BAD lobe im assuming is from a bad lifter...(this was not done by the lifter that exploded... the bad lobe in this pic is on the #5 intake and the exploded lifter was on the #6 intake. this lobe that has a huge divit is on both sides of the lobe and continues over the peak of the lobe to the other side. this im assuming is from a lifter that turned in the bore. (see pics) this would also explain why my spider was bent up, and it cant be a rod bc the rod isnt near this rod (this lobe is below the crank counter weight).

im pretty sure this cam is ruined and that puts me 265$ in the whole, not to mention 120$ for new lifters. what do you guys think? does this look like a failed lifter that grooved the cam lobe?

these 2 pics are of the failed lifter #5 intake lobe.

 

these are of the rod contact on the #6 intake lobe. u can see the round half circle indents.

 

Im also torqueing the rod bolts to 45ftlbs, this is what ARP told me to tq the bolts to with ARP moly lube.

Ive read on a builders site that he would tq his rod bolts to 90ftlbs to get only .005" stretch, but he was using 7/16" ARP rod bolts in an LT1 with oliver rods.

what is the recomended rod bolt tq specs for the ARP 3/8" cap screws just to be sure? 45ftlb seems really low compared to 90ftlbs.

edit: just looked up the specs and apparently it is 45ftlbs.

 

ive been home a week and havent been at work im lost, how can a rod bolt put the mark on the cam hav anything to with the rocker arm?

 

well i guess this got confusing... sry ty_rich, ill sum it up for u.

1.) kept breaking rocker studs and having loose rockers/loud tapping under valve covers, well not loud but too loud for a full roller setup.
2.) a lifter puked its insides all over the inside of my lifter valley.
3.) cam lobe cam in contact a smidge with the #6 rod.
4.) cam lobe on the #5 was severly dented/dimped by a bad (brand new!) lifter.

now the answers in order to the questions above.
1.)rocker studs were breaking due to bad lifters... i would set lash correctly and engine would run great but after a while the lifters wouldnt pump up.... causing too much play in the pushrods, this would cause the pushrods to SMASH into the cup of the rocker and act like a hammer pulling/smacking on the rocker stud. Also excessive play in the pushrod would allow the pushrod to walk to the edge of the lifter and BAM suddenly act like a solid lifter and cause the pushrod to snap. This also caused the exploded lifter.

2.) exploded lifter was caused by too much pushrod play due to poor lifter quality causing the pushrod to catch the wire ring that holds the insides of the lifter inside the lifter, marks were evident on the wire snap ring, this would cause the lifter to explode and shoot its insides in the lifter valley.

3.) cam lobe #6 has bolt groove marks this was easy to see and would have to be a rod bolt. tear down of the engine revealed that i mixed the clearanced and non clearance bolts on the #6 rod, so basically the nonclearanced rod bolt was hitting the lobe, where as the clearanced rob bolt was on the other side. I fixed this and grounded the rods alittle more giving me a min clearance of .068" on cylinders 1,2,5,6... which are the problematic rods on a 383 stroker.

4.) the #5 lobe on the cam has a dent in it and is scored around the top of the lobe from one side to the other... this means lifter issue. since the lobe is not near any of the rods but is on the counter weight side. basically the ;lifters arent pumping up and caused the pushrod to catch the edge of the lifter and suddenly act like like a solid lifter and could dent the softer metal of the cam lobe... this would also cause the lifter to push up to high in the lifter bore and cause the spider tab thats holding the wish bone to bend upwards (which it was).

so in all... all 16 of the brand new speed pro/federal mogul lifters are all CR@P! and can not be used, made in the usa but assembled in india is what they should put on the box! now the lifters have destroyed my 265$ cam, and i have to replace 130$ worth of lifters not to mention it destroyed 2 sets of rocker studs and i need about 80$ worth of gaskets. im pissed

 

I see you are quick to blame the lifters for your woes, but you are ignoring the fact that at least one clearanced bolt was not where it should have been and caused issues. I wonder how many other installation problems there are? Not saying the lifters are not an issue (plenty of solid evidence about the crap quality of Comp lifters out there, speed pro is probably traveling in the same boat), but unless you really find the problem and get things installed correctly, you are potentially going to end up with the same problem again.

I would not reuse any cam thats been adjusted by physical contact. It is entirely possible to crack and not initially break a cam core from contact like that. Ask me how I know this. Then, 20k miles later it breaks into pieces and ejects a rod. So I would not cry over replacing the cam because of "BAD" lifters. The cam is already trashcan material from being contacted by the rod.

That #5 lifter that 'turned' in the bore, if it really did that, is not the fault of the lifter. Either something physically contacted and removed the link plate allowing it to do that, the lifter sailed off the cam due to inadequate pressure resisting that motion (wrong springs, bad harmonics, etc), or the lifters are causing movement of the link plates that they cannot handle. Honestly, the factory setup is fine for many people but there is a point of valve lift combined with cam base circle that can cause issues with the plate. That plate is not supposed to move off the block when in place, nor should the lifter fall below it. If you have parts venturing around in there causing the spider to remove pressure on the plate and allows it to move or come off, then the lifter can easily turn and do some serious damage. So there is another thing for you to check, that the plates are not being lifted off the block or the lifters are not too low. Having used that same cam in a factory block they should be fine, but factory tolerances sometimes leave lots of room for improvement.

Something fishy with your valve spring specs. Not that its a big deal, but there isnt any way you can have 125ish on the seat, 375ish open at .700, and 358ish at .550. Something in one of those numbers is wrong. If the 358 is correct, then its more than 400 at .700 and the rate is 423, higher than any comp spring I see listed. Guessing its a comp cams spring from the 1.46 OD spec. If the 125 and 375 are correct, then it should be about 320 at .550. Anyway, if you have 358 at .550 that should be ok but I'd be concerned that you really have springs in there, installed, that have .720 available space for valve lift. I would personally verify there are no issues before assuming its all fine and dandy, because the specs alone you posted do not agree with one another so who knows if ANY of it is correct. I would just assume its ALL wrong and verify it for yourself so you know exactly what you've got rather than presuming anything of what you were told is true.

 

yes i realize it could be more than the lifters... but the bolt was my mistake and im glad that this was minimal damage but its also annoying for such a small issue to cause the part to be discarded. I have already reordered the XFI 280 cam. the other lobes on the cam are untouched and the engine was spun to 5500rpms... which is my recomended max RPM/peak power, even tho the engine will spin to 6000 without any issues. I checked the other rods and there bolts and they are all correct and fine.I checked clearanced on the #1,2,5,6 rods to cam clearance and found that i have a minimum of .068" clearance... which is more than enough.

Im not sure if the lifter "turned" in the bore but it def scored the cam badly.. worse than the rod bolt did. It almost looks as if the lifter just stopped and was pressed into the lobe of the cam like an inprint of the lifters roller. I know it cant be anything but a lifter bc the lobe is next to the the lobe that would contact the rod bolt. and a crank counterweight wouldnt do that so the only thing left is the lifter.... and not to mention the lifters "roller" the edges were kinda "rolled over" like the edges were rounded off from scraping into the cam.

heres my theory on the rocker/lobe/lifter problems.... starts off with the lifters not pumping up which would cause excessive pushrod play... the pushrod jumps outa the lifter pocket and hits the "clip" that holds the lifters insides together and causes the lifter to become a solid lifter. this inturn pushes too far up on the pushrod and causes the rocker stud to snap (also from excessive wear from the loose pushrods smacking against it) which has fatigued it. This also causes the lifter to push out of the bore enough to push the "bone" that holds the lifter in the block enough to allow the other lifter to spin in the bore and cause the lobe damage. this in turn also bent the spider that was holding the "bone" down. it all makes sense.

the cam is normal base circle and with .576" lift i shouldnt be having any issues with the factory roller block. when adjusting the valves i also looked at the spider/Tbone and saw that none lifted off the block.

The springs arent comp cams... they are assembled by Skips white performance where i bought the heads from, originally they had single 1.25" springs set for .572 lift with a flat tappet cam, i told them i needed the spring upgrade for a .576" roller cam. they said the upgrade included, longer intake valve stems, dual springs good for .720" lift. I then called travis (there head tech guy) at skips white and had him on the phone for 20min and he looked up the specs for my springs... they are...

.720 max lift, 1.46" dual springs
open seat pressure of 125-132lb
closed seat pressure of 375-385 at .700" lift
at .550lift they spec out at 358lb
intake valve stems are .200" longer than stock.

Now i just did the math and my springs rates should increase by 36lb for every 0.1" of lift at the valve... so at .550" lift i should have around 330lb. which is close to the 358lb he stated but i think im still in the range for the springs to be ok. I personally dont have the tools to dissasemble the springs on the heads but my friend does so ill have him come over and verify this. but u are correct madmax. I dnt have tools to measure spring pressure or max spring valve lift.

 

Try to at least just verify you have around .630 of lift before anything contacts with the valve, retainer, and spring if you're using the XFI280 and 1.6 rockers. Then you should be good to go on that. I'm thinking at least the seat and open pressure should be ok from all the spring specs I have seen similar to that size and range.

Hopefully you have no more issues once its all back together.

 

umm, well i have no piston to valve clearance issues... im running SRP forged -16cc dish pistons, not to mention that im running stock deck height and the heads havent been touched. i was running stock felpros with .039" compression thickness but im gona be running .015" rubber coated felpro shims. but ill try the playdoe clearance thing for the valves. how do i kno when the springs are maxed out?

 

Open the valve till something hits. Not talking about piston-valve but rather retainer to valve seal or the spring coils have no more gaps. Anything past about .630 if you have .576 valve lift is fine.

 

ok thanks.. ill try that out but i wont be able to until i get the cam and lifters and set the motor up. unless theres a way without assembling the motor.

 

Gotta pop out one intake spring and one exhaust. Reassemble the locks and retainers on the valve stems, pull up hard (and twist a few times to make sure the locks are full seated) and use the outside measuring fingers of your caliper to measure the distance from the bottom of the retainer to the top of the vavle guide seal. Do this for at least one intake and one exhaust.

Like was said, above, you want at least ~.050" more than whatever your cam lift is.

 

hmm ill see if i can do that. also... wat are you guys recomendations on replacement lifters? i want to keep it stock spider/tbone style. i was wondering if there were a better style brand lifter?

like the comp cams/crane/summits just looks like repackaged stock speed pros... which i cant afford to ruin this new cam.

 

Guy on either LS1LT1.com or CamaroZ28.com had the same issue - well at least part of the same issue - that you had. Broken stud, torn up spider (LT1), broken rocker arm, roller bearings fell all through his engine, etc. Another guy posted photos of two broken rocker arms.

Common denominator, SA rockers. You might want to visit those Forums and do a Search to read about what happened to them, it may help you with your issues.

If cam to rod clearance is an issue, a small base circle cam is an option. I went that route.

I'd sure like to know the part number of those valve springs you were told were good for .720" valve lift. That's WAY over the top. Something's not right with that number.

Look at it this way, if the spring is GOOD for .720" valve lift, you need to add the needed clearrance between the coils of .060" per coil. Now you're looking at a spring with an installed height of right at 1" or more. That can't be right.

I feel your pain, but you're REALLY going to have to pay extra special attention to all the details in putting things back together or you run the real risk of having the same thing happen again.

Best advice I can give right now is not to assume "this caused that", you've got to check closely. Never Assume. It's all about Attention to Detail, that I harp on so often.

Jake

West Point ROCKS! Nation's TOP COLLEGE per forbes Magazine!! Graduation Day Parade 20 May 2010!!!

 

ive already gotten new lifters... i went with the LS7 lifters from GM performance parts.

the spider wasnt torn up... it didnt even look bad until i pulled it off and noticed that the one spider "leg" was bent up more than the others... this seemed to make sense since the lifter turned in the bore and scored the cam lobe... a spun lifter would mean the lifter had to come off the Tbone (pushed up real high) which would cause the bent spider leg.

I wasnt given a part number... i told them i wanted the roller spring upgrade when i got the heads from skips white performance. the specs i stated are right from him. i would def like to test the spring pressures and max lift. when i put the heads on the car i will test the springs for max lift and see how much is left. Im not exactly following u on the .060" clearance between the coils.... u mean that i need to be able to slip a .060" feeler gauge between the coils when fully compressed when turning the engine over?

they said the springs were good for .720 lift... they are upgraded from a single spring to a dual spring. and they had to use .200" longer valves to use these high lift springs. which required me to buy .100" longer than stock pushrods.

IM DEFINITLY being very careful this time... i checked rod/cam clearances and im at a min of .068" which is more than a enough. i checked the bolts and im gona check them again before i put the oil pan back on.

i wish i had a spring rate tester...

 

The generally recommended safe clearance between each coil with the valve at max lift is .060" So, yes, you should be able to slide .060" feeler gauges between each coil with the valve a max lift.

Now, like so many other things, guys sometimes fudge on that number and convince themselves it's okay to do so. Yet for peace of mind and to eliminate the possibility of coil bind and the resulting damage, .060" is what to shoot for AND THAT NUMBER IS A MINIMUM.

I can tell that you're adamant about not replacing your rockers arms and upgrading to 7/16" Non-Self Aligning versions but, as already recommended in this thread, it's one of the best moves you can make. Even CompCams doesn't recommend Self-Aligning rockers in a performance application.

If you take the time to really examine how a S/A rocker is designed to control alignment you'll see the weakness. Two little tabs - one on each side of the roller - that are suppose to bump up against the very tip of the valve stem to keep the rocker arm in alignment. When one of those tabs jumps over the valve stem tip or breaks off, it's carnage time.

If you check those two sites I listed earlier you can see photos of broken tabs and read about S/A rockers found wedged along side the spring, a valve being dropped blowing the engine, etc.

I'm just passing this info along to you for your consideration. I'm not about to get involved in yet another debate over this issue ("I've been running S/A rockers since the beginning of time with no problem" is what I usually get as a response). I'm just trying to help; feel free to do as you please.

Summit, JEGS CompCams and others sell inexpensive valve spring testers that are used with a bench vise. With it you can check seat pressure Vs installed height, open pressure, spring rate, etc. I've got a couple of spring testers but the one for bench vise use is made by ProForm.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

 

ok that i can understand. I will check the spring clearances with .060 feeler gauge but im sure i have more.

well yes ive been runing SA rockers my whole life and never had any issues lol haha jkjk... i understand what your saying... i by no means think they are performance peices but its what i had. I originally bought them as a factory upgrade on the stock L98 heads that required SA rockers. I purchased the new ARP studs bc i need to get this thing on the road, they will be upgraded down the road, studs and rockers. i will get the 7/16 studs and then i will prob get the moly comp cams rockers and guide plates... not sure if ill get stepped guideplates or not yet. My heads came with stepped ones but i cut them off and used it as a spacer.

as far as wat comp cams recomends... im not sure i would listen to them too much. i talked to one of there tech guys and he didnt say anything but " im not gona speculate"... then long periods of silence. Anyone can plug the specs of your engine into there cam selection program and find a cam for there application.

proform huh... thats who makes my rockers lol.

 

CompCams is widely acknowledged as the the #1 valve train company in the country (probably the world). Even Harvey Crane said so in an interview. Now, I'm not going to get into the long list of how many NASCAR teams run Comp's stuff or how many top Pro Stock teams do, too. But if you don't like CompCams, for whatever reason, fine. Choose one that you DO like. ISKY, LUNATI, TPIS, Scoggins-Dickey, A.I., LE, whoever.

As far as guide plates, generally speaking, the higher the pushrod is guided by the plate (within reason of course) the better BUT some heads , like some Darts', come with a specific recommendation NOT to use raised guide plates. So it depends on what heads you're running.

The important thing is to do your homework so this won't happen again.

Best of luck.

Jake

West Point ROCKS! Nation's TOP COLLEGE per Forbes Magazine!! Graduation Day Parade 20 May 2010!!!

 

thats fine, not saying comp cams is bad just that i got a "special" tech guy.

I like comp cams but a close second would be lunati. point is that a cam is a cam doesnt matter who it comes from they are all basically the same. only differences being lobe,lift, duration etc. they all have the same basic similarites. a 230/236 duration and .525/.525 lift and 113 lobe cam from crane and comp are essentially the same cam from different manufactures. so then why buy the comp over the crane? bc u want the name bc u feel theres more trust/quality in someone whos widely used etc.

I will be replacing the rockers/studs when i go turbo or when these break but i dont have the cash now. Not sure what my patriot heads require but they came with stepped guide plates.

ok guys heres an update!! i just spent a couple of hours out in the blizzard were getting in NJ tnite.

I converted 2 of the cr@ppy speed pro lifters to solids and then tested the heads for spring binding. I installed the new cam and spider with only the #1 cylinder Tbone and converted solid lifters. I installed the head (with no head gasket) and tq'd the head bolts to about 50ftlbs around the #1 cylinder. I then installed the pushrods and rockers and made the poly locks hand tight (no need to lash them really since the lifters are solids). i then found the max spring compression at the highest point of lift on the exhaust and then the intake. i slid a feeler gauge in there and found the distance between coils (about 2-3 coils from the retatiner) this was just a minimum test so i didnt try to go for max distance between coils. basically just wanted to make sure i had more than .060" clearance. also i can only check the clearance on the outside spring since the inside spring is unaccessable.

heres the specs.
Exhaust spring= .097" clearance but there was alittle more, this was 2-3 coils down or middle of the spring
Intake spring= .073" clearance but there was alittle more, this was 2-3 coils down or middle of the spring.
this also doesnt take into the account the headgasket compressed thickness, i was using .041" compressed felpro permatorque head gaskets(stock replacement) but now im gona use the felpro 1094 shims with a .015" compressed thickness so add that to the clearances so i def have enough clearance.

this is more than the recomended .060" clearance so there is no spring binding or valve to retainer clearance issues. so im gona have to assume the lifters were just poop. any comments?