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Xe268 wiped lobes

22K views 32 replies 13 participants last post by  1969chevyss 
#1 ·
Hey guys I have a 355 short block with a xe268h cam stuffed in her. I have a set of vortec heads that I will get new springs to accomodate the extra lift. My question however is this, are there any other good lifters besides the ones that comp cam recommend(812-16) that will help me prevent the chances of my cam going flat. I have been doing a lot of reading and this seems to be a reaccuring problem with this grind. My next question is for my vortec heads, what sprints can I use that will drop right in without any machine work. I read that z28 springs from northern for 525 lift will work, just would like to get you guys opinion on the matter. Thanks in advance.
 
#4 ·
As F-Bird says, if you listen to guys that don't do any research they will rawdog Comp Cams all day long. In reality when Johnson and a couple other lifter mfg's quit making lifters for a while a chit load of cheap crappy Chinese lifters came across that were made of inferior material....hence wiped out lifters and accompanying cam lobes. Johnson is back in business but if F-Bird says use the GM lifters then use them, he is a man that knows of what he speaks.

You can also do a search function on this forum..."cam break in" or something of that nature and you'll get all kinds of info. Most very good and then some not very good.
 
#5 ·
From what I've been reading, Johnson makes alot of people lifters, trick is to find out which ones. I found a guy name Mike Jones from Jones cams and they sell Johnson lifters. I think even the Speed pro are made by them too, but I will do some calling around and find out for sure. I went on Summit and found these GM Performance lifters for a 350 sbc part number 12371044. Not sure if these are the ones that you were referring to as the GM Heavy duty or not.
 
#7 ·
Comp Cams

Compcams flat tappet hydraulic failure rate is unacceptable. They know there is a problem and their answer is to keep their fingers crossed and hope for the best. I really like the Compcams grinds but I would not use anything from Comp again. When a cam fails, this requires a complete teardown. Will Comp stand behind the product. Hit and miss. If they know the XE series has high fail rates, why woudn't they nitride all cams in this series. It's simple, it's about customer service and doing the right thing, not excuses. How many out there are using Comp xe series cams? Did your cam fail?
 
#9 ·
Studebaker said:
Compcams flat tappet hydraulic failure rate is unacceptable. They know there is a problem and their answer is to keep their fingers crossed and hope for the best. I really like the Compcams grinds but I would not use anything from Comp again. When a cam fails, this requires a complete teardown. Will Comp stand behind the product. Hit and miss. If they know the XE series has high fail rates, why woudn't they nitride all cams in this series. It's simple, it's about customer service and doing the right thing, not excuses. How many out there are using Comp xe series cams? Did your cam fail?
comp,cams failures are caused by lack of correct oil, and the fact that they have a problem with a line of fakes, being sold as comps.
We've never had a camp.s go flat, but we use the correct oil, liter springs for break in, and buy directly from comp. bypassing the chance of being sold a fake(counterfit) . that a major speed shop is halking.
 
#12 ·
techinspector1 said:
Geez, what is it with you knuckleheads and these extreme grind cams?????:spank:
Have you not heard and read enough horror stories yet?????:spank:
I have NOW. LOL, I have been leaning toward the crower 60918, or lunatis 60901lk. I think the crower is a tad rowdier, but not much.
It will be for a 400 pontiac (389 block @4.120) zero deck,82 CC heads , if anyone GAS. :thumbup:
 

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#13 ·
CNC BLOCKS NE said:
When ordering a flat tappet cam always order a P-55 cam core and use only GM lifters with the steel bottom and use a good oil.

I use a lot of flat tappet cams in my circle track engines never been an issue in 38 years.

I use CENPECO 20/50 oil which has 2300 PPM of zinc.

What do you mean a P-55 cam core, is that cast iron material and what is the part number for the GM lifters.
 
#14 ·
techinspector1 said:
Geez, what is it with you knuckleheads and these extreme grind cams?????:spank:
Have you not heard and read enough horror stories yet?????:spank:

The 268 has to be a good grind cam, because people are still buying them. Wouldn't using the right quality lifters, correct cam break in and correct oil during and after break in work? I'm just trying not to buy an new cam, but if I keep reading and getting you guys opinions, I probably will. Thats why I'm not in a hurry to complete this build. I spent almost a month deciding on buying the right oil pump to make sure I didnt get one that will break off on me, there is alot info about that out there too, but most of the problems of the articles i have read were a few years ago and I assume that Melling has fixed that problem now, but since I wasn't sure I sure installed the 10553 Select series pump.
 
#17 ·
Studebaker said:
Compcams flat tappet hydraulic failure rate is unacceptable. They know there is a problem and their answer is to keep their fingers crossed and hope for the best. I really like the Compcams grinds but I would not use anything from Comp again. When a cam fails, this requires a complete teardown. Will Comp stand behind the product. Hit and miss. If they know the XE series has high fail rates, why woudn't they nitride all cams in this series. It's simple, it's about customer service and doing the right thing, not excuses. How many out there are using Comp xe series cams? Did your cam fail?
No mines is brand new stuffed in the short block now, but I do not want to have to deal with it later, so I'm just looking at swapping out the cam with a good set of lifter now.
 
#18 · (Edited)
1969chevyss said:
The 268 has to be a good grind cam, because people are still buying them.
Your logic is flawed. People still eat red meat and fat, knowing full-well that it will clog their arteries and may cause heart disease. Just because people buy these fosdick grinds does not mean that they are any good.

Read through this tutorial and see what you're missing....
http://www.crankshaftcoalition.com/wiki/Camshaft_install_tips_and_tricks
 
#19 ·
I will definitely read the article and decide on a new cam and lifter. Before I bought the cam I made a thread on what will be the best cam for my build and this was what was recommended. Now since I have found out how poor these cams lobe wear is, now it's not a good cam. I will read some more on this matter and if anyone has anymore input feel free to post back. Thanks
 
#21 ·
I have no problem machining the guide bosses for more lift if I have to. I was originally looking at the comp xe262 so maybe the isky 264 would work for me. I'm not sure what grind cam I have in my 350 now until I pull it out of the car but the sound is good enough for me with the custom exhaust I have. I'm calling isky in the morning and ask out the 264 and 268 grinds.
 
#24 ·
Does any of this stuff apply to the FORD 302 HIGH energy cam (not extreme energy)? I am looking at a comp cams 31-255-5 computer controlled cam, which on the camquest dyno software puts me at 330 ft lb, which is more than a stock 351 (which is what I am going for).

However I am scared to death about changing the cam. I cant afford to rebuild the engine if I wipe a lobe out....
 
#25 ·
Well I dont think the desktop dyno can be too terribly far off. Its only 50ft lb over what my engine is rated at stock. The engine IS stock but will be getting headers and exhaust and a K&N filter. Who knows what else. Also I might have to advance the cam a little to push the torque curve down - I am planning on doing some towing with this truck. About 6,000 worth.

Still yet, even if i only gain 30 ft lb, that puts me equal to a chevy 350 of the same year. 350s tow OK.

Big thing tho is still the fear of wiping out a cam. I know the engines are a good bit different between the SBC and SBF.
 
#26 ·
I called Isky this morning and they recommended the 264 Mega. This camed will give me more low end torque with a noticeble lope at idle but nothing to extreme. He said he have heard from people that the 264 Mega out perfomed some xe268h. The Mega 268 would fit my combo as well if I was planning on changing the stock gears and converter. I'm glad I brought this issue up now and not later causing me to tear the motor down for a flat cam. I know it is still up to me to break in the cam right and use the right oil additives.
 
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