isotropic superfinishing - camshaft

[Schwuppes]

Hey people,

has anyone used this proccess before? Apparently its finishes the metal surface down to a nanometer scale or something like that. they chuck its into some sort vibrating bowl together with these pellets and then dip it into a chemical solution afterwards. Comes out mirror finished and supersmooth and randomized surface finish... apparently its used in serious race engine to reduce friction etc.

Since these motors are know to spin cam bearings on occassion after swapping cams... Im wondering whether this would be a extra assurance

Any thoughts, experiences?

Cheers

[Bio248]

sounds pretty expensive when a whole new motor is $500.

[Schwuppes]

here in Australia I'd be lucky to get one under $1500

[Scottydoggs]

cam bearing are cheap enough to change. and easy enough if the engine is out of the car. then theres no reason to worry.

[Schwuppes]

yer but the engine isnt out of the car... when the cam bearing spins it will send all sorts of crap throught the motor... so it will need a full rebuild... thats at least 3 grand right there. I can't rebuild myself, don't have the knowledge or time.

[Bio248]

when i said 'new' motor, i meant a 'new' junkyard motor. no one buys a 0 miles motor unless they are crazy.

a lot of the issues come when the coolant isn't flushed out of the motor properly. dump a quart down the valley and wash the coolant down into the pan, do an oil change and just run it idling for a bit, do another oil change, etc.

i find that most of the time these motors die because of a mistake made when working on them. otherwise they really are tanks.

[Scottydoggs]

how high are the miles on your engine? lots of people here do cam up grades and never change the bearings, and they also dont have failures. not that ive heard of any way. and people here tend to cam engines with up to 200,000 miles with no issues.


id think you'd loose oil pressure before a cam bearing would let go and shred like a crank or rod bearing.

[Schwuppes]

when i said 'new' motor, i meant a 'new' junkyard motor. no one buys a 0 miles motor unless they are crazy.

a lot of the issues come when the coolant isn't flushed out of the motor properly. dump a quart down the valley and wash the coolant down into the pan, do an oil change and just run it idling for a bit, do another oil change, etc.

i find that most of the time these motors die because of a mistake made when working on them. otherwise they really are tanks.

yep, and i'm talking about a junk yeard engine with 150.000km too I bought my motor + gearbox for $2100 AUD last year... and thats the standard price for a motor + box combo. Prices are a little different over here

There is no coolant in my motor and oil pressure is at around 50 - 55 PSI idle and 60 at cruise. So it seems to be pretty healthy.... it has 170.000km on it which is roughly 110.000 miles.

[Bio248]

there will be coolant in the motor when you have to take the LIM off and take the lifters out so you can get the cam out, too. if you can manage to take the LIM off without dumping coolant you're a god.

[Schwuppes]

ah ok i understand now... my bad. Ill be getting the work done by my performance workshop anyway... I'll be sure to mention that.

[Schwuppes]

but hang on... why dont you just drain all the coolant first? Or impossible to get rid of all of it?

[Bio248]

you won't be able to completely drain it, there will still be some in there that'll dump when you crack it off the gaskets. it's not really a super concern so long as they make sure they flush it so that the coolant makes it into the oil pan so they can drain it.

[Scottydoggs]

when i did my lim gaskets i took the dog bones off then rocked the engine to the back and forward as far as i could push and pull it, this helped the coolant left in the lim to move over the lip inside the lim. then i broke the plastic cooling elbow then popped the lim loose then lifted it as level as possible, not a drop of coolant leaked out of the lim. i didnt even do a oil change when i was done.

[QUICKSILVER462]

New machine or reconditioned bearing surface is all that is needed for a street/strip engine. Problems arise from improper assembly procedure, not correcting worn surfaces, not checking and/or correcting bearing oil clearances. Special surface treating or polishing is only needed for sustained high RPM.