Thread: What would cause this lifter failure (pics attached)

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Originally Posted by DennyW

From reading your discription, I would say to check your clearances on the cam bearings. If the clearance is tighter on 1 or 2, and the rest are looser, guess what ? The tight ones will starve on oil.

Also, never rule out the new parts. I have gotten a few that were bad right out of the box.

The hardness depth on stock Chevy cams in general are not very deep, and it doesn't take long to go through that if not properly done on the breakin.

Note: I was talking to a engine builder, and he told me that 2 cams from Lunati had went flat on him. He switched, and no more problem. I'm not knocking them at all, cause I know they have good products. Just a note on this is all.

Chipped lifters indicate chatter. Make sure you use a slick oil. Also, if the lifter holes are mis aligned in relation to the cam lobes, or the ramp on the cam is to steep.

Denny,I would guess the Lunati cam failure was due to the lifter crown and not the cam it's self.

Originally Posted by DennyW

Maybe, but that's not what Dave told me. We went to college together for automotive in the 70's, and he has been doing engines of all types for years. He said they were telling him he didn't break the cam in right. I know better than that myself. This guy is very fussy when he builds an engine. Clean room, and the whole nine yards. The third cam, he used another brand, same procedure, and no failure. That was in the same engine the other 2 cams were installed. That was his final test to see if it was the cam, or an engine problem. So the same engine was used. It is still racing the track.

ps, Bill, I'm not advertising this. Just showing that the guy that told me has lots of experience in this field. I took address and phone number off his card.

In our IMCA mod. engines we had a couple cam problems and after checking into a few area's we found brand new lifters from two different cam companies that had a small dish in the lifter face rather than a crown.

Originally Posted by DennyW

Yes, that happens also. That's one reason I mentioned that it could have been the lifters. Maybe the Monday, Friday thing, or the checking of clearances slipped by a few of them. Now, you never know where you may get your parts from. If you see sand, or taco sauce in the box, take them back.

I know what you are saying about the sand or taco sauce.
I had a brand new set of TRW pistons that I had bought about 12 to 15 years ago that had a little to much taco sauce on them.
I think that was when I switched to JE/SRP.

Guys, I've heard of those type of problems with Lunati cams and I seem to remember that Crane had the same type of problems a few years back.
The old Isky 30/30 cam I've got has been in three differeent sbc's and I've never had a problem with it. BTW, the last time I looked on Isky's site the cam listed for a little over $600.

Does anyone remember when the oil companies started to take zinc out of their oil.
I wonder with a flat tappet cam how much this will effect things?

Denny,take a look at this web site.www.JoeGibbsRacingOil.com
Then click under Why use JGR oil?
If you scroll down father you will also see some info. from Exxon.

Denny, is it safe to assume that you're not a fan of Lucas oil additive?
Since I bought the '91 Dakota with 145 plus on the clock I've used that along with Castol high mileage 5W-30 oil. It's a 318 with TBI and at the present time I don't want to rebuild as the engine doesn't smoke and uses less than a quart between oil changes (300 miles). What would you recommend?

Originally Posted by NTFDAY

Denny, is it safe to assume that you're not a fan of Lucas oil additive?
Since I bought the '91 Dakota with 145 plus on the clock I've used that along with Castol high mileage 5W-30 oil. It's a 318 with TBI and at the present time I don't want to rebuild as the engine doesn't smoke and uses less than a quart between oil changes (300 miles). What would you recommend?

We used the Lucas in every race engine we built up until last year.
No problems.
It really seemed to help our oil temp. more than anything else.

Thanks, Denny.
So far I've gotten the mileage to almost 17MPG which I think is pretty good for this truck.

Originally Posted by DennyW

They are on my own good to use list. And, you have living proof it works. Keep using it.

I try to use what works on a particular engine type. If the seat spring pressure is 115-150, a good quality oil will work great. As miles pile up, they need a little extra to keep going. I just feel that some additives are just a money catcher. There's just a handful that really do good things inside an engine.

If you are going beyond the the normal range of engine building, with spring pressures exceeding 150-400 lbs, the normal range, by all means, use the slickest, toughest oil products you can find.

Hey denny how do i found out what my seat pressure is? the only "pressure" numbers i can find on my valve train is just the spring rate of 417 lbs/in

heres the springs that my cam calls for and currently using: http://store.summitracing.com/partde...0&autoview=sku

edit: Nevermind. i'm sturpid. hah summit also provides that information somewhre else: Seat Pressure at Installed Height (lbs) 105 lbs. LOL
so i guess i'm not in that much need for mega-oil

Originally Posted by DennyW

Really good info. If you notice though, after 1.5 hours or so, (100-150 laps), they do say drain and replace oil for extended protection. It sounds like good stuff, but I use this, Schaeffer for years, and have had really good results. You must understand that I don't do full out racing, but have done some serious street and early drag races. Most of my replies are related to guys that build things for fun, street race, and do not have money for the big buck engines. (That sure would be nice though).

When I have built engines on a regular bases, I would build them to exceed what ever the customer wanted. I pretty much blue printed all the motors I did, even the daily drivers.

I know things are changing, and sometimes I fall behind a little on the latest changes.

http://www.cincy-racing.com/schaeffer/news.htm

The XP1 oil is for engines that operate at 250 F,over 9,500 rpm's,and 500 miles.
In the last year we have tightend up all our oil clearance's and we run a mix of the XP1 and the XP3.
We use to take out the inner spring on our flat tappet engines now we just use the "break in oil " for all the flat tappet engines.
We simply bring the rpm's up to about 2,500 and vary them every 2 min. up and down about 500 rpm's we break the cam in for about 25 min. with this method.We have had zero failures in over 35 engines.
We have also upped are seat pressure another 10 lbs. on the last 8 engines.
Are we right? Are we lucky?I don't know but so far so good.