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Jonnylightening

Jonnylightening

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Hey guys awhile back I bought a set of EQ heads and threw them on my 77 LA 318. Over the past month ive been having problems. First off one of my rocker studs wiggled loose and i dropped a rocker and blew the lifter out of the bore. At first I thought it was a bad lifter (summit brand) but end up it just being the rocker stud. For piece of mind since it was apart I put a brand new set of Howards lifters in (hyd. Flat tap). This past weekend I got a popping sound comming from the engine. Turns out I broke a rocker stud. So i desided im taking my heads to the machine shop and get them drilled and tapped to 7/16 plus im going to run a girdle. I figured I should bullet proof it so it doesnt happen again. So upon taking the heads off I noticed my cam looked funny. Come to find out 4 of my 16 Howards lifters have concaves on them... Now before anyone asks I did do the cam break in to a T. I used almost a whole bottle of Lucas assembly lube, Howards zinc addative, lucas 10w40 Hot Rod oil (High Zinc), primed my oil and carburetor so it was instant fire up, and hit 2200-2500 instantly after startup for a timed 20 minutes. At this point im frustrated with hydraulic flat tappet lifters. So my question is what lifters (solid roller) will work with my 318LA with EQ heads? When I bought my hyd. Flat taps I used AMC style due to oiling.
 
Almost all solid rollers have a pushrod oiling or non option. Cranes do for sure
 
Not much use to you now, but in future with a flat tappet, don't use high Zinc oil AND a Zinc additive. You probably ended up with at least 4 times the minimum needed PPM of ZDDP, if not more, and excess ZDDP has been reported to cause other issues like spalling. Those issues started showing up with a bit over 2x the old levels of ZDDP.

With the stud problems, I am curious as to how much spring pressure you are using and your max RPM's?
 
I was limited to .500 lift with my magnum heads due to coil bind using the stock length valves. I used the 7.625 pushrods that Mopar sold, but I had to go back and make them a little longer because the rocker was bottoming on the stud. This cost me a cam. You may want to check that while it is apart.

Allen
 
nm9stheham said:
Not much use to you now, but in future with a flat tappet, don't use high Zinc oil AND a Zinc additive. You probably ended up with at least 4 times the minimum needed PPM of ZDDP, if not more, and excess ZDDP has been reported to cause other issues like spalling. Those issues started showing up with a bit over 2x the old levels of ZDDP.

With the stud problems, I am curious as to how much spring pressure you are using and your max RPM's?
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Good to know for future. My spring pressure is right around 300# i believe but being the studs i had were 5/16 to 3/8 might have been the issue
 
moparallen said:
I was limited to .500 lift with my magnum heads due to coil bind using the stock length valves. I used the 7.625 pushrods that Mopar sold, but I had to go back and make them a little longer because the rocker was bottoming on the stud. This cost me a cam. You may want to check that while it is apart.

Allen
Click to expand...
The cam I was using was a summit cam .454 lift with 1.5 ratio rockers. I have the 1.6 PRW roller tip rockers due to the heads being a magnum replacement.
 
I called lunati and gave them my specs and they reccomendes theyre 40200730 cam. Would I have a problem with the lifts of it with the 1.6 rocker ratio? What if anything would I need to do to run it?

Solid Roller Cam. Good high performance street cam with good mid range torque and HP. Works well in 318-360 c.i. motors. Needs 2500 RPM stall converter or 4-speed transmission, header, 9:1+ compression ratio and 3.55+ gearing. Lopey idle. ; Advertised Duration (Int/Exh): 261/267; Duration @ .050 (Int/Exh): 231/237; Gross Valve Lift (Int/Exh): .555/.566; LSA/ICL: 110/106; Valve Lash (Int/Exh): 016/016; RPM Range: 2400-6400; Includes: Cam Only
 
When cams go flat, it will break parts, but you need to also pay close attention to your rocker geometry, because screwed up geometry can ruin cams too.
 
replicaracer43 said:
When cams go flat, it will break parts, but you need to also pay close attention to your rocker geometry, because screwed up geometry can ruin cams too.
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Everything checked good my first go round with the cam roller tip rode mid valve stem. I just changed lifters because since it was apart i felt howards were better quality vs summit brand white box
 
Jonnylightening said:
Good to know for future. My spring pressure is right around 300# i believe but being the studs i had were 5/16 to 3/8 might have been the issue
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Very doubtful the studs being 5/16” is the issue. Stud quality (or lack of) more believable. But cant rule it out i guess but the spring pressure you have is not up there. Something else in the valvetrain and the geometry likely. Im running Hughes #1110 single springs (120# seat, 320#@ .550”) with Comp Cams 5/16” studs among other Comp valvetrain components on my EQ heads (1.6 rr and .517” lift) pushed slightly over 6000rpm often, many 1/8 and 1/4 mile runs and no issues. Id be looking at geometry, clearances etc
 
12many said:
Very doubtful the studs being 5/16” is the issue. Stud quality (or lack of) more believable. But cant rule it out i guess but the spring pressure you have is not up there. Something else in the valvetrain and the geometry likely. Im running Hughes #1110 single springs (120# seat, 320#@ .550”) with Comp Cams 5/16” studs among other Comp valvetrain components on my EQ heads (1.6 rr and .517” lift) pushed slightly over 6000rpm often, many 1/8 and 1/4 mile runs and no issues. Id be looking at geometry, clearances etc
Click to expand...
Im planning on changing out everything just need to find a cam thatll work
 
You are pushing well into the upper 500's lift range with that cam. Looks to me like a complete overhaul of the valvetrain will be needed.

So with 4 bad lobes, you ARE taking the engine apart to clean out all the metal, correct?
 
nm9stheham said:
You are pushing well into the upper 500's lift range with that cam. Looks to me like a complete overhaul of the valvetrain will be needed.

So with 4 bad lobes, you ARE taking the engine apart to clean out all the metal, correct?
Click to expand...
Unfortunately yes...another reason im so pissed. My current engine only had 20,000 original miles. So basically $200 worth of **** parts is going to cost me $1000+
 
Jonnylightening said:
Solid Roller Cam. Good high performance street cam with good mid range torque and HP. Works well in 318-360 c.i. motors. Needs 2500 RPM stall converter or 4-speed transmission, header, 9:1+ compression ratio and 3.55+ gearing. Lopey idle. ; Advertised Duration (Int/Exh): 261/267; Duration @ .050 (Int/Exh): 231/237; Gross Valve Lift (Int/Exh): .555/.566; LSA/ICL: 110/106; Valve Lash (Int/Exh): 016/016; RPM Range: 2400-6400; Includes: Cam Only
Click to expand...
IMO
this might be too much cam for a lo-compression 1977 318, in a streeter. 9/1Scr at 200ft elevation is already chewing up your cylinder pressure, requiring IMO more than a 2500TC with 3.55s.... Forget it if you are at 1000 or higher.
The advertised duration has no qualifier, so your seat to seat could be vastly more, and that would kill your cylinder pressure, turning you engine into a Jeckle and Hyde personality; namely a dog until say 3500, then coming on strong at the top, peaking at around or after 5200, then rapidly descending into a pit, I'm guessing.

The take-away is this;.
I highly recommend that you NOT order a cam until you have determined your EXACT compression ratio.
 
Jonnylightening said:
Unfortunately yes...another reason im so pissed. My current engine only had 20,000 original miles. So basically $200 worth of **** parts is going to cost me $1000+
Click to expand...
Glad to hear about the clean up; that is wise.

The valvetrain upgrade you are facing is more than fixing broken parts. You are putting in much heavier lifters and the lift rates are going to be much higher. And you have unknown rocker geometry. So there are at least 2 things that are requiring more spring pressure and valvetrain strength, and the geometry may makes it all worse.

I'll say again that the rollers being centered on the valve tips is not any indication of good geometry. The main thing you want to look for there is how wide the scrub pattern has been. Do you have a pix to share of the present scrub pattern on a valve tip?
 
AJ/FormS said:
IMO
this might be too much cam for a lo-compression 1977 318, in a streeter. 9/1Scr at 200ft elevation is already chewing up your cylinder pressure, requiring IMO more than a 2500TC with 3.55s.... Forget it if you are at 1000 or higher.
The advertised duration has no qualifier, so your seat to seat could be vastly more, and that would kill your cylinder pressure, turning you engine into a Jeckle and Hyde personality; namely a dog until say 3500, then coming on strong at the top, peaking at around or after 5200, then rapidly descending into a pit, I'm guessing.

The take-away is this;.
I highly recommend that you NOT order a cam until you have determined your EXACT compression ratio.
Click to expand...
AJ, Ima thinkin' that Lunati measures their advertised durations at .015" lifter lift, like most other mfr's do for solids.

OP, to AJ's point, how do you use this engine/car?
 
nm9stheham said:
Glad to hear about the clean up; that is wise.

The valvetrain upgrade you are facing is more than fixing broken parts. You are putting in much heavier lifters and the lift rates are going to be much higher. And you have unknown rocker geometry. So there are at least 2 things that are requiring more spring pressure and valvetrain strength, and the geometry may makes it all worse.

I'll say again that the rollers being centered on the valve tips is not any indication of good geometry. The main thing you want to look for there is how wide the scrub pattern has been. Do you have a pix to share of the present scrub pattern on a valve tip?
Click to expand...
I will get you some here once I get home. I think since ill have it apart im gunna swap pistons side to side
 
nm9stheham said:
AJ, Ima thinkin' that Lunati measures their advertised durations at .015" lifter lift, like most other mfr's do for solids.

OP, to AJ's point, how do you use this engine/car?
Click to expand...
Street strip is the plan. I gutted it out for the most part. Relocated the battery to the trunk and added a fuel cell. Like I said I have a 2500 stall with 3.91 rear gears
 
If you are having issues with a HFT the LAST thing you need is a solid roller. How are you going to get enough valve spring on it? I say 200 on the seat is the sweet spot, and 180 is the bare assed minimum. If Lunati says less, they are lying or stupid.

5/16 pushrods are marginal for a SFT and way too flimsy for any solid roller, unless you can get .116 wall stuff, and even then it ain’t a SBC. The lifter side rocker geometry on SBM is atrocious at best.

My suggestion to the OP is to take a breath or two, slow down and figure out why this cam went flat and fix that. You already have roller rockers...why not a good solid flat tappet grind? 130 on the seat and 320ish over the nose and if it’s not some Comp MM style lobe it should be drop dead reliable.

As NM pointed out above do not keep adding zinc to the oil. Zinc is required, but more zinc isn’t good. When you mix crap like that, you make very Tribologist in the country flip their collective lids. Any oil worth a crap is designed as a complete package. When the end user adds crap to it, you change the balance of the additive package of the oil.

My suggestion is to use a break in oil next time. A real, dedicated break in oil, and add nothing to it, unless you are a certified tribologist and know exactly what you are doing.

Most cam failures happen on initial fire up. The engine gets cranked on too much, and by too much I mean it should fire up just like it will when it’s tuned correctly. There should be fuel in the carb, the distributor should be set at a MINIMUM of 40 total so when the engine is at break in RPM you have that much total on it. Retarded timing generates heat, and heat kills parts.

You must verify everything before cracking it off...full battery. Known good ignition. Known working carb. Get it running and get the RPM up to 2200-2500 and then vary the RPM a bit to keep the oil splash on the cam and keep the lifters rotating.

Which reminds me of another issue. Lifters that are too tight in the bores and the lifter doesn’t rotate. This is a lobe killer. With a light oil on the lifter it should slide down the lifter bore on its own weight. If it won’t, stop and fix it. Blocks that have been thermally clean and shot blasted almost always have lifter bore issues as the top of the bore gets peened over and the lifter will slide into the bore but not rotate.

It’s time for a slow, methodical autopsy on this and find the reason for the failure. A solid roller isn't the cure for everything cam failure related.
 
yellow rose said:
If you are having issues with a HFT the LAST thing you need is a solid roller. How are you going to get enough valve spring on it? I say 200 on the seat is the sweet spot, and 180 is the bare assed minimum. If Lunati says less, they are lying or stupid.

5/16 pushrods are marginal for a SFT and way too flimsy for any solid roller, unless you can get .116 wall stuff, and even then it ain’t a SBC. The lifter side rocker geometry on SBM is atrocious at best.

My suggestion to the OP is to take a breath or two, slow down and figure out why this cam went flat and fix that. You already have roller rockers...why not a good solid flat tappet grind? 130 on the seat and 320ish over the nose and if it’s not some Comp MM style lobe it should be drop dead reliable.

As NM pointed out above do not keep adding zinc to the oil. Zinc is required, but more zinc isn’t good. When you mix crap like that, you make very Tribologist in the country flip their collective lids. Any oil worth a crap is designed as a complete package. When the end user adds crap to it, you change the balance of the additive package of the oil.

My suggestion is to use a break in oil next time. A real, dedicated break in oil, and add nothing to it, unless you are a certified tribologist and know exactly what you are doing.

Most cam failures happen on initial fire up. The engine gets cranked on too much, and by too much I mean it should fire up just like it will when it’s tuned correctly. There should be fuel in the carb, the distributor should be set at a MINIMUM of 40 total so when the engine is at break in RPM you have that much total on it. Retarded timing generates heat, and heat kills parts.

You must verify everything before cracking it off...full battery. Known good ignition. Known working carb. Get it running and get the RPM up to 2200-2500 and then vary the RPM a bit to keep the oil splash on the cam and keep the lifters rotating.

Which reminds me of another issue. Lifters that are too tight in the bores and the lifter doesn’t rotate. This is a lobe killer. With a light oil on the lifter it should slide down the lifter bore on its own weight. If it won’t, stop and fix it. Blocks that have been thermally clean and shot blasted almost always have lifter bore issues as the top of the bore gets peened over and the lifter will slide into the bore but not rotate.

It’s time for a slow, methodical autopsy on this and find the reason for the failure. A solid roller isn't the cure for everything cam failure related.
Click to expand...
Im not disagreeing at all, all im bitching about is how can I break a cam in with cheap Summit lifters change nothing else but to Howards and flatten lobes? I ran the car 2000 miles with the cam and summit lifters that were in it. Only reason I changed out was for piece of mind, Howards were supposed to be top quality high performance good for higher RPM revs. All I know is Im done with anything flat tappet.
 
NM
most grinders use .020 or did
Jones uses lash +.006
so it works out the same as a HFR or HR
SAE published by the big grinders works well also
SAE is .006 AT THE VALVE so it also compensates for lash and rocker ratio
 
Wyrmrider said:
NM
most grinders use .020 or did
Jones uses lash +.006
so it works out the same as a HFR or HR
SAE published by the big grinders works well also
SAE is .006 AT THE VALVE so it also compensates for lash and rocker ratio
Click to expand...
Sinnds good wyrm...many thanks as usual. And it makes a lot of sense to do it at the valve +.006.
 
Jonnylightening said:
Im not disagreeing at all, all im bitching about is how can I break a cam in with cheap Summit lifters change nothing else but to Howards and flatten lobes? I ran the car 2000 miles with the cam and summit lifters that were in it. Only reason I changed out was for piece of mind, Howards were supposed to be top quality high performance good for higher RPM revs. All I know is Im done with anything flat tappet.
Click to expand...
And ain't saying you should not be unhappy, OP. What we don't know is if those lobes were already damaged and the Howards just finish it off....

Now YR's point on the lifters not rotating is a very good one. Story time: We had a virgin block to work with and found that 4 of the Crane supplied lifters were tight in the bores. So we wrote back to Crane and asked if they could measure some and find some smaller than .***" diameter due to the unusual block situation. They seemed happy to oblige and the smaller ones were in the mail 2 days later.

So, the Howards lifters could have been on the high end of diameter tolerance and been a bit too snug in 4 of the bores.

FWIW, everyone should make the effort with flat tappets to
  • Mark the lifters
  • Turn the engine over 4 times when assembled
  • Check to see that each lifter has rotated, at least a little bit; they will rotate at different rates.
Yeah, does not fix the op's engine now....
 
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