I recently upgraded from a 350 to a fresh 455 in my '72 Cutlass. Several of you have helped with advice which I appreciate.....well....could use some more. I used a Comp cams xe268 flat tappet cam with all of the corresponding goodies from Comp. I followed the breaking procedure and unfortunately just about 300 miles into it the cam is shot with several lobes starting to go away. I am extremely disappointed and thoroughly frustrated at the thought of tearing into this fresh motor.

I have three questions. First, any advice for pulling the timing cover while in the car? I'm not pulling this motor again and obviously can't drop the pan in the car. I don't want to mess up the pan gasket. Second, does anyone know if I will have to pull the condenser out to have enough room to pull the cam? Finally, I am going with a roller set up, XR276 from Comp, since it will work with the springs and roller rockers that I already have. The parts are ordered, but I want to know if there is anything special that I should be aware of when going to a roller set up? I have seen several threads about the cam bolt and noted comments from Joe about the distributor gear assisting in keeping most of the force pulling rear with the cam but I am not clear about whether or not I need to do anything special to ensure play is not excessive.

Thanks.

 

Far as I know, if you pull the radiator you have just enough room to pull the cam without pulling the condenser.

I'll leave the other questions for those who know better.

- Eric

 

You'll need to undo the front bolts on the pan enough to drop it a bit. That makes getting the front cover off and on a bit easier.
I don't know who told you that you can use the same springs, and I don't know what springs you have, but very seldom will the same spring work on both a flat tappet and roller.
So the first cam from Comp went south and now you're buying another? Hmmmmm.....
You'll need a cam button of some sort as well as degreeing it.
Good luck with the Comp roller lifters, you might want to check out all the complaints before you install them. That's why I don't sell them.

 

It is easy to lose a flat tappet cam with modern EPA friendly oil. They need a lot of ZDDP etc. high pressure additives. Comp sells additive and oil because of this.

 

X2....I didn't know about this ZDDP issue until I read about it. Fortunately, the builder gave me a break in additive when I picked up the motor. I now use ZDDP additive in my oil changes. Is it possible to flatten a cam in 300 miles? That sounds a little odd to me, but I'm no oil expert either.

 

IMHO, if the cam is broken in correctly from first startup, it's not going to go "flat" 100 miles later. Good oil with a ZDDP additive is insurance.

 

If you change to a hydraulic roller cam think about getting a Lunati and cutlassEFTI sells them and knows his products well, also use Brad Penn oil period that will eliminate the oil problems even if you use a roller cam. and if you go back to flat tappet make sure to use a break in additive and Brad Penn oil. The cam button helps keep the cam from walking forward and you dont have to take out the evaporator or grills you have plenty of room. It is possible to flatten a cam out with the new oils that have zero protection for flat tappet cams. Good luck and like I said give CutlassEFI a pm on what cam to run with your combo he wont steer you wrong!

 

Thanks for the input. I did run Brad Penn oil for the start up and followed the proceedure....thoroughly frustrating! The only reason I am looking at the XR276 is that Comp does indicate that this cam uses the same springs that came with the XE268 that has failed. These are installed now and I really have no desire to take the heads apart.

Here is a photo of the engine as in came apart - prior to rebuild. This is the old chain and gears, but the cam button / bolt shown here is the same one I reinstalled. I assume that there are not various versions of this..??

 

Comp Cams cams have a 30yr history of being soft and their hydraulic lifters , flat or roller, are junk. Their cam profiles for Oldsmobiles are not that great either.
That being said. Don't buy another Comp cam. Get ahold of CutlassEFI and let him help you out. You'll be glad you did.
Get a stick magnet and fish the oil pan for the iron from the cam lobes. You'll never get it all but you can get a lot of it. When you have the front cover off pour several gallons of kerosene into the pan as fast as you can in an attempt to wash out as much as possible through the oil drain hole.
Before you try to pull the cam out take the bolts out of the condenser mounts and gently lay it down as best you can. It doesn't gain a lot of room but its the little bit you need to make it easier.

 

X2, thank you Smitty.
Also, I'm a little concerned about the springs. If they said they're fine for both then they were either on the stiff side for a flat tappet, which may have added to your problems, or maybe light for a roller. What spring did you install and at what height? You need to verify that one way or another.

 

Thanks Smitty I was thinking It was just me who had bad luck with comp cams and I did not like any of their grinds, Lunati has worked for me everytime but I have heard recently they have changed hands and are not the same? Not to steal the thread but which cams are you using on a regular basis?

 

I've was using Bullet almost exclusively. I've recently began using a different can man for my custom grinds. He was once heavily involved in factory racing teams and has simulation programs that are the latest and greatest. Each cam is CNC ground and the spec sheets are to the first decimal point. I've found that the engines acceleration rate on the dyno is smoother and stronger across the entire power range. The only downside is cost. He's a bit on the high side, but you get what you pay for.
I'm giving Crower a shot on a current build. Years ago they had very good grinds. So I'm giving them another shot.
So many if the aftermarket companies are held by holding corporations that are just milking them for every penny they can that is disturbing. Lunati has been passed around multiple times. Crane is same way. Once great companies raped then rebuilt and then raped again.

 

that looks like a factory bolt which should be fine you can an aftermarket thrust bolt in different lengths...i would double check your parts and make sure you have the correct springs etc...and i wouldnt necessarily condem comp cams for this and go out and buy a different brand....how do you know for sure the lobes are flat? are you racing this thing

 

I use Lunati for my roller and Erson for my flat tappets.
Virtually all the major cam companies use a CNC to grind their cams. They have for years.
However recently I just had a Comp and Lunati roller that had issues. The Lunati had threads that needed to be retapped. The Comp had the #1 journal unfinished, it wasn't ground all the way to the end so the bronze washer wouldn't fit. Both Lunati and Comp quality control missed them. But I give Comp the worse rating, they should have seen the journal problem, I did from two feet away.

 

Smitty that is an absolute true statement about the cam companies, I live near Daytona and Crane was great back in the 70s and 80s same with Lunati, I used a Crower back in the early 70s and my car ran like crazy but I wanted more power and ran a solid lifter Lunati and it did run better but not alot, I had Waibel competition do all the machine work and Terry Schafer was the greatest RIP. They taught me most of what I know and Buddy Ingersoll. I have wiped out one cam an Erson from Super Shops back in the 80s and it was a complete kit with roller rockers, IT HAPPENS!!

 

I really appreciate all of the feedback. I wish I had reached out to cutlassefi earlier on about the cam as I would have gone that route up front. That said I am in a tough spot now. The valve springs that are installed are the ones that came with the kit for the XE268. They are the same part number, 995-16, that are called for with the XR276. I really do not want to take the heads apart here. I'm deeper into this upgrade than I really planned already.

I soooo appreciate the input from everyone here and find it very valuable. At the end of the day cam preference is undoubtedly as controversial as Pepsi vs Coke, but I am honestly struggling a bit with the idea that all Comp cams are bad. They sell a ton of them. Has anyone used the XR276 successfully in an olds engine? I'm not trying to talk myself into something for sure, just curious if there are any positive comp cam experiences out there....

Frustrating to say the least! Should be enjoying spring with the top down.....not tearing the darn thing apart again.

 

I don't have experience with Comp role roller cams, but I've ran the same XE274H in two different builds for thousands of miles with 0 issues.

 

I have run many Comp Cams, most of them purchased in the 1970s and 1980s. I bought a large XE from them in 2005 and it has been perfect. I also bought a solid cam from them about 3 years ago, and had them nitride it. It is still fine. A friend bought a large magnum series hydraulic for his 400 a few years ago and the engine dyno'ed over 400 HP.


In my experience, they open and close the valves just fine with good and relatively smooth dynamics and the secret to getting an "Olds grind" instead of a "Chevy grind" or some other lies in picking the right lobes and lobe center. Others have mentioned different preferences and experience above, and you have to expect such differences in advice.

 

Joades I have had many many comp cams in fact I have 3 right now and I have a brand new set of the 995-16 springs and they came with the 298 magnum and the 304 Magnum so it sounds like you did everything right and especially with the Brad Penn oil!! So call Comp Cams and make them give you another cam or at least a big DISCOUNT on another one with FREE SHIPPING!! and give it another try and like Smitty said run alot of mineral spirits thru and fish around the bottom with a magnet to clean it out then you should be fine like I said it happened to me and s..t happens it just could have been a bad cam. I worked as a machinist and sometimes a bad one will slip thru.

 

Engine has to come out to clean the block thoroughly.


There is metal particles in all the oil passages.


I would not do anything until the block is clean.


Or, another failure is in your near term future.

 

i agree with this... unfortunatly if you just replace the cam with metal parts floating around that would be a half measure fix

 

If he had an oil filter on it then there should be no contamination of the galleys. Cams that go flat don't put out chunks of debris. They wear away in fine powder like particles. Many many people have had a cam go flat and put a new one in without issue. Should there be a failure down the road he's really only out the gasket set.

 

that would be good news...did he find any solid metal under the valve covers?

 

I agree with Smitty on this one as I wiped out a cam and I flushed the engine cleaned the pan and took off the valve covers and cleaned and inspected everything put in the new cam and lifters broke it in and changed the oil right after the break in and then again after 500 miles and drove it for 30 thousand miles of drag racing and hard driving.

 

Well your going to be a gambling man with that strategy...better check the lifters and say a prayer for all the bearings

 

Well I might have been lucky but I have had broken pushrods at the track and broke roller rockers arms and pieces of metal everywhere with some pushrods broken in pieces and the timing chain in pieces and did the same on those flushed and used a magnet, changed the oil and filter and kept racing. If his budget can stand it I would say take it apart and clean everything but sometimes you do the best that you can afford to do and like Smitty said the cam turns to powder as the lobes wear. JMO

 

Well, I tore into it this weekend. Surprisingly the cam does not appear damaged to the naked eye, though the dial indicator would disagree. I did find two visibly broken lifters, though neither was on the valves that earlier had misteriously increased in lash. These had both broken the retainers that keep the plunger in. I'm sure that this probably accounts for much if the noise. While glad to not see hunks of cam missing, the missing retainers were a concern. As I am this far into it I pulled the motor mounts loose, broke out the joist, and raised it enough to pull the pan. Found the missing metal in there and cleaned it all out.

Since I have the roller cam in hand I changed out the flat tappet 268. I don't trust it at this point and certainly don't want to throw new lifters at it. Next challenge appears to be pushrods. Comp recommended 7783-16 which are 9.000 inch. They aren't even close to long enough. The rocker binds up before it makes contact. I assume I am hosed and need to order a length checker which I am in the process of doing. I'll chat with comp tomorrow. The old cam came with 9.547" pushrods. Those will mount up but they appear to be too long event to the eye. They put the roller on the outter edge of the valve step on the base lobe.

Since I am obviously not in "kit' mode at this point, anybody have any good pointers on how to set this up right? I get that you want the wear mark in the middle of the stem, but doesn't it move across the step a bit during operation? Should it be in the middle when on the base lobe?

The photos attached are a crude layout of the pushrods that I have now.

Picture one gives you the idea of how much shorter the entire assembly is. The roller has the rocker that was recommended with it and the flat tappet has the one that was in the engine with it.

Picture two is just for kicks showing both lifters using the OLD pushrods from the flat tappet cam that was just removed. Obviously much longer on the overall assembly so I am needing something in the middle.

 

I cant see pics on my phone and not familar with that set up but what about just getting a few adjutable set up push rods

 

Yes quit dealing with the pimply faced kids reading off a screen at Comp cams.
You should have returned everything to Comp and gone with the advice given. They don't have a clue.

You're probably going to need around a 9.300 pushrod, but that depends on the rocker, stem height, deck height etc. But only guys on here who have done this would know, not Comp Cams. And a 995-16 spring is a bit stiff for a flat tappet, especially the open pressure. The typical installed height on early Olds heads is about 1.650-1.680. If you put that spring in at that height that could have been the cause of your trouble in the first place.

Sorry but I get a little testy when someone asks for help then doesn't heed the advice given. However I wish you the best in your endeavor.

 

Wow...there you go, lol i guess thats what 1939 germany was like

 

I dunno - I don't think I've heard of German cars wiping cams.

- Eric

 

Joades you should get an adjustable pushrod so you can find the exact size push rod and I have had lots of trouble in the past with comps push rods but I know alot of people who have had no trouble just saying thats been my experience and the 995-16s are too much for that valve spring height but thats moot, you have to have the right springs set at the right height and pressure for that roller. JUST LET CUTLASS EFI help you get things right on the cam!!! Thats what he does and he knows his Cams take a look at the 468 build and the comments on that engine! and with chunks of metal I would take it apart clean everything and reassemble it you have spent so much time and money and you dont want to do it all over again! especially since retainers and lifters broke thats alot of metal. The only thing you will be out of is a little more time and a gasket set, but get that cam,, lifters pushrod length, springs, pressure, height and the right retainers and keepers!! and degree the cam. like I said Mark knows his stuff and will help you get that motor running right!

 

Did the spring pressure match up to spribg installed height