Roller cam bearings

I have about 20 1/4 mile pass on an engine I built last summer.It is 528 steel crank aluminum head engine solid roller cam. While in staging line last weekend at idle i herd squeling from the engine and then it died. Towed it back to the pits. turned the motor over by hand and seemed to be alright so I started the engine and it fired up. The oil pressure had dropped 10 psi from 60 at idle to 50 psi. I thought maybe the noise cam from the starter maybe it stayed ingage. So i made another pass and ran tenth faster then any other pass that weekend. I was concerned about the loss in oil pressure so when I got home I dropped the oil pan and found cam bearing all mangled up in the oilpan. I looked up into the engine with the pan off and i can see another cam bearing walking its way out. My question is should I be running roller cam bearings. I am going to have roller cam bearings installed to save this block but is this something I should have installed when I built this engine.

Its probably the result of not enough bearing clearance to start with so few passes on it. I don't think the roller cam bearings are a must , but I have ran them in the past with no problems , just make sure who ever bores the cam tunnel gets it straight .

You may have to run roller cam bearings now that the bearings have spun.....or maybe not, depending on the damage to the housing bore, if any.
Most cam bearing issues are due to lack of clearance, oil delivery or both. Unless one has very high RPM and spring pressures the non-roller bearings will work very well.

WOW, I'm surprised it would effect it by a tenth. Glad you caught it and didn't destroy the engine.

IMO something doesn't sound right about this deal. The camshaft had to be in a severe bind to kill the bearings and then the car go a tenth quicker. I'm thinking you have a cracked block. Check the main webbing carefully before you spend any more money on it.

Charlie

I had the exact same situation on my first 460. It started as a crate motor, and I upgraded to a Comp Cams XR292R roller cam. Upon noticing a drop in oil pressure, I dropped the pan and found #3 cam bearing munched up in a wad at the bottom of the oil pan, and #2 cam bearing half way out of its bore. At that time, the concensus was that the Clevite cam bearings have a tendency to "stick" to steel cams at start up, causing the cam bearing to be slowly turned in it's bore until the oil feed becomes blocked, and the bearing self destructs. My machine shop checked the cam bores, and #3 was at the very outside of the tolerance, so I decided to take a chance on the rollerized cam bearings. The bearings themselves are not that expensive, about $35.00, but the machine work, and installation was about $450.00, but on the bright side - I havent had any problems with them in several thousand miles of driving. A much cheaper alternative would be to get the cam bores checked, if they're okay, have your machine shop install some coated Durabond cam bearings. That's my story, and I'm sticking to it!

Wayne (SAWDOFF) Pearce

Can someone explain to me why a person will painstakingly set main & rod bearing clearances and then check their cam bearing clearance with a simple "the camshaft turns" measure...?

Spun cam bearings in a 385 engine happens a LOT because of not enough oil clearance, (or simply not enough supplied oil), at the cam journals.

Thanks for all the responses. When puting this engine together all clearences where checked and where in spec. I will post a pic of the bearing and you can see that the bearing didn't heat up or starve for oil. I will check the block over to see if any main webs a cracked. The engine should be out tonight hopefully. And again thanks for the replies. Aaron

Same thing happened to me. I installed a solid roller cam and it tossed bearing #3.
Went with the roller bearings. The machining may seem expensive, but it less than the cost of a new cam and a tear down and put back together even if you count your time at minimum wage.

I don't know about BBF's specifically, but I hear a lot of big HP guys switching away from roller cam brgs. They make more HP with flat bearings and far less hassle. Harmonics are better, parts last longer, etc. Some are running aluminum bearings, although I don't know any specifics about that. If your cam bores are screwed up, you could have them bored and/or honed and easily make aluminum bearings to the new OD and have the ID's honed in the block. Then you'd know your clearances and your cam tunnel would be straight and true.

64 fairlane wrote:Thanks for all the responses. When puting this engine together all clearences where checked and where in spec. I will post a pic of the bearing and you can see that the bearing didn't heat up or starve for oil. I will check the block over to see if any main webs a cracked. The engine should be out tonight hopefully. And again thanks for the replies. Aaron

How did you check clearance on a roller beaaring?

Scott Foxwell wrote:How did you check clearance on a roller beaaring?

It wasn't a roller bearing that failed.

After installation, the needle roller's spec may be checked with a tapered plug gauge. The spec is 2.1256"-2.1271".

For the complete FRPP Needle Roller Installation Instructions, Click HERE.

Paul

Curt wrote:

Scott Foxwell wrote:How did you check clearance on a roller beaaring?

It wasn't a roller bearing that failed.

I don't think I said it was, but thanks for answering for 64Fairlane.

Paul Kane wrote:After installation, the needle roller's spec may be checked with a tapered plug gauge. The spec is 2.1256"-2.1271".

For the complete FRPP Needle Roller Installation Instructions, Click HERE.

Paul

Thanks Mr Kane.

Paul Kane wrote:After installation, the needle roller's spec may be checked with a tapered plug gauge. The spec is 2.1256"-2.1271".

For the complete FRPP Needle Roller Installation Instructions, Click HERE.

Paul

thanks Paul! i'm about to put some in my eliminator block and this helps.