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  #41  
Old 04-03-2024, 10:45 PM
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Originally Posted by steve25 View Post
Is that push rod straight?
Was there not enough retainer to guide clearance?

Just grabbing at straws here since the only other reason to me would be the core was hardened uneven.
Pushrod is straight. 60thou+ clearance. Engine still ran great.

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
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  #42  
Old 04-03-2024, 10:49 PM
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Originally Posted by 65 Lamnas View Post
Well...that sucks. Sorry to learn of this.

Do you always use the same brand and grade of oil?
Not always but i try to use good oil. Been using 10w40 full or semi synthetic. Ived used plenty of mobil1 and brad penn in this engine but not always. Always use wix filters

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
([_|_] ##\|/##[_|_])
  #43  
Old 04-03-2024, 10:59 PM
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Originally Posted by 78w72 View Post
I bought my 1st set of comp lifters from dave at SD in 2012, had the engine/car running in 2013.. it ran great but had the notorious hyd roller ticking, dave suggested adding some seafoam to the oil to see if it would clean out any debris from manufacturing but it didnt work.

He replaced the lifters under warranty with the "new" S comp lifters that came out in early to mid 2014, replaced them in late 2014 according to my notes. So these lifters werent the shavers, look like my originals from the pics, either johnson or morel.

Is it possible the lifter wheel wasnt hardened right to cause that damage? Pretty sure the OF cams were billet, thats why they require a poly or brass dist gear. Bearings could be bad too but still roll ok under no load?
This whole roller set up parts from dave and setup by his specs. Cam lifters spring package cups. Should only be 146lbs on the seat. And i replaced the spring 5 years ago for no reason other than preventative maintenance due to relatively high lift and mileage. Yes to me the roller bearing feel OK spinning it with my fingers

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
([_|_] ##\|/##[_|_])
  #44  
Old 04-03-2024, 11:05 PM
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Originally Posted by Steve C. View Post
On the all the copies of SD Performance cam cards I have on hand they have either part # 51-000-9 or # 51-000-11

The last number, both the 9 or 11 indicate 'Steel Billet Roller'.


.
This is OF comp from Dave i think 2012. Im sure i can dig up the paperwork if you think it might make a difference. I remember its billet, i dressed the dist gear and ran a composite on it with no problems.

Im still leaning towards a cam failure not a lifter failure. The other lobes vary in appearance but none of the other have degraded to this level. They are inconsistant for sure

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
([_|_] ##\|/##[_|_])
  #45  
Old 04-03-2024, 11:14 PM
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Originally Posted by mgarblik View Post
Fortunately you caught this before there was catastrophic damage. The damage you have is manageable. Why did this happen specifically on one lobe? That can be hashed out in these posts forever without a clear answer. As one of the few on the forum who still have little issue with flat tappet cams, this is just one more example that a roller is not a 100% cure for wiped cam lobes. It did enjoy a pretty good life span for a performance engine. In the time period you purchased and installed these lifters, Comp and many others were sourcing lifter wheels and needle bearings from various Chinese vendors. There were a considerable number of failures as we know and everyone was pointing fingers and blaming suppliers. So much so that in this time frame Crower began making all the wheels in house and axles. Also only US sourced needles. That is not the case today as they feel they have found some quality imports for some components. All we can do as end users is try to buy the very best components we can afford and cross our fingers. Hope you can get it all back together and save that camshaft.
I really don't think i want to save this cam because i am suspect and don't know for sure that its a good core. Im thinking rings bearings and new cam and lifters. Yes i am glad i caught it when i did, could have been worse. But we still know metal been circulating

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
([_|_] ##\|/##[_|_])
  #46  
Old 04-04-2024, 12:19 AM
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Quote:
Originally Posted by jonmachota78 View Post
I really don't think i want to save this cam because i am suspect and don't know for sure that its a good core. Im thinking rings bearings and new cam and lifters. Yes i am glad i caught it when i did, could have been worse. But we still know metal been circulating
It is doubtful you could save it anyway. Yes it is a Billet cam, but like most HR grinds from Comp it is one of the lesser quality billet 5150 or 8660 cores, the induction hardening is thinner than a 8620 billets, not as tough as the 8620 either. That is why SR cams often cost more than HR cams, SR’s are ground on tougher more expensive cores.

  #47  
Old 04-04-2024, 05:51 PM
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Comp told me 200 on the seats if running solid rollers on their hyd roller cams.FWIW,Tom

  #48  
Old 04-04-2024, 05:53 PM
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Sorry,forgot you had hyd rollers on it!Brain fart.Tom

  #49  
Old 04-05-2024, 08:02 AM
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Originally Posted by Jay S View Post
It is doubtful you could save it anyway. Yes it is a Billet cam, but like most HR grinds from Comp it is one of the lesser quality billet 5150 or 8660 cores, the induction hardening is thinner than a 8620 billets, not as tough as the 8620 either. That is why SR cams often cost more than HR cams, SR’s are ground on tougher more expensive cores.
I didn’t write that quite correctly, the 5150 (common HR’s) and 8660 are lesser quality cores than a 8620, but the hardening on those cores actually is deeper than a 8620. The issue is more the 5150 and 8660 get used on a wider variety of profiles and you can find that the hardened depth gets to thin to regrind.


Last edited by Jay S; 04-05-2024 at 08:19 AM.
  #50  
Old 04-05-2024, 11:14 AM
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I had a single lobe on a CC HR (billet, not sure which one) repaired by CC and it worked out well.

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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
  #51  
Old 04-05-2024, 12:07 PM
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Interesting.

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
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  #52  
Old 04-05-2024, 12:19 PM
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Call them up and tell them the SN of your cam and they will know if it can be fixed.

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1967 Firechicken, 499", Edl heads, 262/266@0.050" duration and 0.627"/0.643 lift SR cam, 3.90 gear, 28" tire, 3550#. 10.01@134.3 mph with a 1.45 60'. Still WAY under the rollbar rule.
  #53  
Old 04-05-2024, 12:41 PM
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My concern is how to make sure this doesn't happen again. Whats the most reliabe street/strip setup going these days?

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
([_|_] ##\|/##[_|_])
  #54  
Old 04-05-2024, 12:55 PM
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Not directly related to the above question but it was interesting despite being old....

CONSUMERS RANK THE BEST CAMSHAFT BRANDS

https://hedgescompany.com/blog/2012/...etical%20order).


.

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  #55  
Old 04-05-2024, 01:39 PM
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Quote:
Originally Posted by jonmachota78 View Post
My concern is how to make sure this doesn't happen again. Whats the most reliabe street/strip setup going these days?
Considering you had 12 years on this, I don't know that I'd necessarily say it was unreliable. I think in a street/strip modified hotrod playground like this, we have to have realistic expectations.

I'm dealing with my own 10 year issues on my build and it sucks as it's all kind of snowballing a little bit. But I do think that some of these things that we use have to be thought of as wear items to an extent.

I think if we want to get 50K+ and 20 years of service out of these parts, they are going to have to be engineered closer to OEM specs. If we use the LS engines as an example, we know they use lazy lobes and low springs pressures. They also benefit from much lighter valvetrain components.

So, this means we likely need to look at older, lazier cam lobes and look to making the valvetrain as light and as stable as possible. This may mean looking to things like beehive springs with titanium retainers and lighter valves than we typically run. We need to be able to get the spring pressures down.

Without being able to do that, I think the lifters specifically, have a shelf life.

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  #56  
Old 04-05-2024, 09:48 PM
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Without getting too detailed on what you could do different, for how yours failed, an improvement would be to have that HR cam ground on a 8620 core next go around. The 8620 surface is tougher, it wouldn’t flake out as easy. The Bullet HR cam I have in my TA is on an 8620 core.

  #57  
Old 04-05-2024, 10:07 PM
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If I was to build a new street engine I would do acomp hyd roller cam based on the Magnum lobes and run 1.50 rockers.I would use lightweight valves maybe smaller stems and light weight retainers and would hope they would be able to use like 130-140 on the seats .FWIW.Tom

  #58  
Old 04-06-2024, 07:55 AM
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That's what Ive always strived to do with engine builds Tom. Make the drivetrain parts as light as possible in the hopes that I can run less spring pressure to control things.

Pontiacs are almost as bad as other engine makes like big Chevy and big ford when it comes to valvetrain weight.

One reason I like the parts AFR uses in their heads. They are the only aftermarket head I'm aware of that uses an 8mm valve stem. Everyone else uses 11/32. It's only cutting ounces but that's the goal.

By doing things like that on my BBC, which are terrible for valve train weight, even though I still run 150 lbs on the seat, it's gone 25 years and thousands of miles without a valve cover removed and spins 6500 on a hydraulic roller with a 2.25 intake valve. I would imagine after all these years the valve springs might have 140 lbs or even less spring pressure.

Not positive any of that helps but I've had excellent success knock on wood.

Other things you could look into is cryo treating. Things like springs etc... the 327 my son is doing he had Paul cryo treat the entire engine, valve train, block, crank etc....this one is being built to rpm with a hydraulic roller and make some steam with a peanut motor

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  #59  
Old 04-06-2024, 08:07 AM
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If it had a OF cam it would have had all magnum lobes. OF2 has more aggressive XR’s on the intakes

  #60  
Old 04-07-2024, 12:15 PM
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Thanks for the input guys that helps. Yes this cam has magnum lobes. Jon

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'78 Macho T/A DKM#95, 460cid, SRP pistons, KRE 310 D ports,
3" pypes, Hooker 1 3/4" headers, hydraulic roller,
10" Continental, 3.42 gears
11.5 @117.5mph 3900lbs
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