Tragic event has occurred!

[68 C-10 KID]

Upon warm up on the motor the other weekend. I was getting mean green ready to head down to my friends shop to Install a pair of Moroso trick springs. My cam chewed up my roller lifter and dropped metal shavings all over 1 and 2 piston and then started in on the others. Great news is the system one oil filter did its job and the mains and rods are still in good shape. The bad news is the motor had to be bored. Luckily it cleaned up with a .040 bore and not a .060. New SRP pistons and rings on the way!

The machinist looked at the cam and lifters and he believes Isky ground the cam on to big of a blank and they ground past the hardness. It had pitting and bad wear into the lobes, Damn the bad luck. Has anyone ran into this before? Its a billet cam.
I need to send my lifters back to Isky and have them rebuilt. Should I send the cam back to and ask whats wrong with there bump stick?

I Have bought a new cam. specs are 106 lobe sep on a 268 274 dur with a .666 lift. The old cam was a 108 lobe sep on 260 260 with a .642 .642
I haven't been to impressed with single pattern cams so I hope this one works well.
So this is how my drag season started for me.

[bigboybodry]

Man that sucks!!!!!! Sounds like some of my luck. If i had any questions I wouldn't be scared to ask. If they have a problem they need to know about it anyway. Good luck with the new engine and glad you didn't have to go .060.

[68 C-10 KID]

Yep. If it wasn't from bad luck I wouldn't have any luck at all. The .060 was a special order only. I couldn't find a 6" rod .060 piston anywhere.

[bigboybodry]

I ran into that with a 505 I built I couldn't find a true nos piston that bore and ended up spending 1200 on a set of custom wisco. I did order 10 to have 2 spare just in case though.
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[nxtruck]

Hate to hear that. I guess the way to look at it is that it could'a been worse. Hope you get it up and running soon!

[djracer]

Sorry for your loss. Good luck with getting it fixed.

[Geoff]

That sucks man...as you know from the PM's I sent yuh been there done that & it sucks....hope that new cam works out for yuh also.....Should still be darn nasty

[68 C-10 KID]

All the new go fast goodies came in Thursday.
SRP pistons w/ mahle rings
All bearings and gaskets
Titanium retainers and ARP 2000 rod bolts
oil pump and bolt on pick up tube
timing belt
MSD Pro billet dist.
Now just waiting my turn in the machine shop!
I hope every ones season starts off with wicked evil good RT's and go fast ET's
Have fun be safe.

[68 C-10 KID]

Some interesting things I have learned in the last few days.
Afr heads use a 8 mm valve and take a special stepped retainer. Order from AFR or get the Manley number.
Eagle rods use a ARP bolt proprietary to them. Order from Eagle or a Eagle dealer. Or buy a better rod.
So its been a learning curve for me.
Isky finally got back to me and told me that the malfunction was due to coil bind and the lifters we bouncing on the cam. I called BS! on that. I told them no way in heck that a .640 lift cam would coil bind a pair of AFR 227's.
I talked to my machinist he seems to think they ground the cam on to big of a blank and ground past the hardness.
I'm currently looking for a set of 1 7/8" tube headers to compliment the new cam.
Hope every ones year is going well.

[PGSigns]

Couple of questions on your setup. How many runs on the lifters? What valve springs are in it and what lift are they good for with the installed height you have with the heads. What seat pressure on the springs and had any gotten soft since the last check. How is the push rod length and any marks on the bottom of the rockers. Some cam profiles are hard on lifters. They make good power but the rollers don't do well with the profile and can have as short as 50 runs and need to be replaced. We only rum Comp stuff or the good Crower's.
Jimmy

[68 C-10 KID]

1.550" OD Roller Dual Valve Spring, 225 lbs on seat, .710" maximum lift
I didn't change a thing on them. They are the Race ready out of the box.
The push stick length is on point. I made sure my valve geometry was dead on.
The bottom of the rockers didn't looked bet up.
Well the lifters are there High dollar models. No junk.
I checked all the springs with the Moroso tester and all of them were fine.
I honestly couldn't tell you how many times its been down the track or how many street miles are on it.
I would hate to think those lifters are only good for 50 passes. The lifters were in good condition, just the cam lobes were junk.

[redhead69]

Sorry to hear about your motor but hopefully the new stuff will make it faster! Hopefully I'll get to see that thing run at woodburn or PIR soon!!

[bigsnookmaster]

What lifters were you running? I have Isky Red Zone with the E-Z roll option. I've been driving them on the street with a .577 mechanical roller for about a year with no problems. They cost about $900 bucks though! I was curious if you are using these, or needle bearing roller lifters.

[68 C-10 KID]

redhead69,
Ya I also hope it picks a little up also. You are not the only one let me tell you. I'm about to have a fit if I don't get to make a pass soon.

bigsnookmaster,
I also have the Isky Red Zone lifters with the E-Z roll. I don't believe the lifter gave up on me. It was the cam blank they ground.
I think this is the part number. Isky 1271-LSH
I sent the lifters away in the original box.
Another thing is I use real good oil.
http://www.bradpennracing.com/

Thank for everyone thoughts and outlooks.

[redhead69]

Dont worry.. another rain out today.. next weekend doesnt look good either

[68 C-10 KID]

Good news, I got to pick up my block, rotating assembly and heads outfitted with tie retainers!
I just might have to start grinding my rings and knock in some cam bearings. :-}

[wildearp]

Be absolutely sure your springs are rated for your roller cam. You will have to deal with some ugly harmonics if they aren't. This doesn't just mean pressure and lift specs, they need to be specifically what that cam manufacturer requires.

Are you running a stud girdle? How about the AFR hydra rev kit?

[68 C-10 KID]

I'm running shaft mount Jessel rockers on the heads.
I was told there shouldn't be a need to run a rev kit. I have good thick push sticks from smith bros.
I also don't take the motor past 7200rpm.
I looked into the factory specs of the heads and what Isky was calling out.The springs fell into the correct range.


Isky fixed the cam for $150
and rebuilt my lifters for $225

[wildearp]

Thick pushrods can be pretty heavy. Same with rockers if they are steel. I don't know what the Jesels are. My point is the roller cam I ran really floated the valves quickly. Maybe call Isky and ask for their specific recommendations. I went purely on lift and pressure specs and cracked an entire set of springs due to the harmonics of the roller cam. When I called the cam manufacturer, they knew exactly what happened before I could get the words out. They sold me the correct springs at cost. A professional engine builder and racer either missed this, or didn't bother to check it. Do your self a favor and make the call.

Even with the correct springs, they floated very quickly, on a SBC, well under 7000 rpm. I wish I had ran the rev kit.

[Super73]

Lobe shape has much more of a negative effect on valve control than lift does. Two cams with the same lift, one with a lot of duration vs shorter duration, the longer duration one (generally speaking) will be easier to control than the more aggressive short duration lobe.

However, many other things come in to play here, such as intended RPM range, lifter weight, push rod weight, spring weight, retainer weight, rocker ratio/weight and where the weight of the rocker is (60% over the nose vs 50% over the nose).

Spring design has changed dramatically in the last 10 years. Less people run tripple springs, dampners, and extreamly high rates due to this improved technology.

[stich626]

Originally Posted by 68 C-10 KID

Upon warm up on the motor the other weekend. I was getting mean green ready to head down to my friends shop to Install a pair of Moroso trick springs. My cam chewed up my roller lifter and dropped metal shavings all over 1 and 2 piston and then started in on the others. Great news is the system one oil filter did its job and the mains and rods are still in good shape. The bad news is the motor had to be bored. Luckily it cleaned up with a .040 bore and not a .060. New SRP pistons and rings on the way!

The machinist looked at the cam and lifters and he believes Isky ground the cam on to big of a blank and they ground past the hardness. It had pitting and bad wear into the lobes, Damn the bad luck. Has anyone ran into this before? Its a billet cam.
I need to send my lifters back to Isky and have them rebuilt. Should I send the cam back to and ask whats wrong with there bump stick?

I Have bought a new cam. specs are 106 lobe sep on a 268 274 dur with a .666 lift. The old cam was a 108 lobe sep on 260 260 with a .642 .642
I haven't been to impressed with single pattern cams so I hope this one works well.
So this is how my drag season started for me.

I'd love to know why , they think the cam ate the roller lifter..????
99.995 of the time it's the roller lifter that failed.. not the cam, that had a rolling wheel rolling over it..

[68 C-10 KID]

Isky claims that the lifters were bouncing on the lobes due to floating the valves.

Looks like my elitist of a machinist and my self need to go to class and learn how to set up heads for cam specs then.

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[68 C-10 KID]

Well, I pulled the pin on a set of headers Sunday @ the local parts trade show.
I picked up some Headmans 1 7/8" to 2" w/ 3 1/2" collector. I would imagine this thing is going to breath just fine.
http://www.summitracing.com/parts/HED-65022-6/

I should start the engine assembly next week. I will keep everyone posted.

[68 C-10 KID]

Started the assembly process this week. Waiting on a ring grinder from power house tools. So I can drop the slugs in. Tomorrow I will work on the cam timing.

[shortbed70]

Wow sounds like you've come along way with this motor. I can't wait to see and hear this thing run in a video. When you hoping to have it togather
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