I have a brand new set of JUN3 that are going in my car this weekend. I was told that I need to lightly sand the lobes to make them smooth before I put them on the head .. All I can say is WTF ?!?! Is there any truth to this ?? I don't want to mess up this VERY EXPENSIVE set of cams ... Thanks !!

 

sounds like a cruel april f00lz joke...

my JUN3s werent sanded down lol

 

It's not a joke - TODA recommends the same thing for their cams.

I polished my journals on a lathe with powdered pumice first and then jeweler's rouge. They were almost like mirrors afterwards.

As long as you are using a very fine abrasive - no harm done. The metal is very hard and unless you are using a very heavy grit - you will not change the cam profile.

BPR - who loves polishing metal

 

BPR - who loves polishing metal[/QUOTE]

Sounds like a good idea...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Big Phat R &raquo;</TD></TR><TR><TD CLASS="quote">It's not a joke - TODA recommends the same thing for their cams.

I polished my journals on a lathe with powdered pumice first and then jeweler's rouge. They were almost like mirrors afterwards.

As long as you are using a very fine abrasive - no harm done. The metal is very hard and unless you are using a very heavy grit - you will not change the cam profile.

BPR - who loves polishing metal</TD></TR></TABLE>

Could there be any potential problems in the future if you don't polish the cams?

 

BPR, that makes sense. I was thinking more along the lines of 60 grit so I was like WTH?

metal polishing

 

skunk2 never mentioned this, those bastards

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RTW DC2 &raquo;</TD></TR><TR><TD CLASS="quote">BPR, that makes sense. I was thinking more along the lines of 60 grit so I was like WTH?

metal polishing </TD></TR></TABLE>

60 grit is too much. You're not sanding wood! Go with 400 minimum - I advise wet sanding if you are doing it by hand. Powdered pumice is like 800-1000 grit

The key is "light touch"

Now show me "sand da cam" Daniel-san.

"HAI Miyagi-san!"!

 

Dont these aftermarket cams already come with very polished lobes? I never payed attention to what mine looked like when I got them.

 

Instructions for break in for my Jun cams never mentioned this

 

I spoke to my mechanic about this and he says that the idea is merely to polish the lobes NOT actually sand them.. I looked at my cams and they are really not that smooth so I figure there must be some truth to this "wet sanding/polishing" deal ..

 

I say do it. Less friction = good.

This brings up another point though. What about repolishing the cams after they have been used, and you take them out. For instance, Im gonna be replacing my retainers soon, and Im wondering if it would be a good idea to polish up the lobes and rockers since Im in there? Obviously the key would be not over polish it and create flat spots or uneven areas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RTW DC2 &raquo;</TD></TR><TR><TD CLASS="quote">I say do it. Less friction = good.

This brings up another point though. What about repolishing the cams after they have been used, and you take them out. For instance, Im gonna be replacing my retainers soon, and Im wondering if it would be a good idea to polish up the lobes and rockers since Im in there? Obviously the key would be not over polish it and create flat spots or uneven areas. </TD></TR></TABLE>

I would assume that they would already be somewhat "polished" from the continuous contact with the rocker pads, so this might not be necessary.

 

Use break in lube....apply it all over the cams. Then install them and let the car idle for 20 min. then change the oil.This is what jun says to do in the manual...This has the same effect!

 

Hmm... I didn't get any kind of documentation with my cams And yes, they are brand new in the box

 

I would follow what Nasi said. Lube it up!!

 

I say until you get an answer straight from JUN, don't listen to forum wivestales.

 

i never sanded my JUNs...
used a lot of asembly lube tho...

 

I've tried contacting JUN about this but they don't answer my emails .. Without a doubt, the cams are getting lubed when they go in .. I'll see what I can find out .. If anyone has some official JUN documentation about this, please let me know !! Thanks !!

 

I'll post the JUN documentation when I get home