Im assuming that the reason my opti died was that my dowel pin is to long. It installed it the way it came from comp and after doing a search that is a likely cause for my problem.
In the post I read it said the dowel pin from comp comes .840 inches long, mine needs to be .620 long since I did a vented opti conversion.

What is the best way to go about this? Measure two tenths and grind it off? Im not going to take the cam out of the car so Im going to mask and cover everything real good except for the dowel pin.

To anyone who has had to grind down their dowel pin, how did you do it?

Also does it have to be exactly .620 or can it be .610, .615, etc

 

I was told a dremel tool

 

I used a dremel tool and just marked the dowel pin with a permanent marker.

 

I wanna make sure I do this right this time. I have a dremel....how did you guys measure a mic? a ruler etc? I just dont wanna screw up again and blow another opti.

 

We just pounded the dowel in as far as it would go and used a mic as we ground it with a air powered grinder. Constantly measuring as we went.

That dowel is made out of some pretty stout steel. I can't imagine how long it would take with a Dremel!

I chamfered the tip of the dowel a bit for an easier insertion in the opti. I didn't want a sharp lip. The dia of the dowel is .250 max. so don't mushroom the tip as it is ground down.

 

Yeah, I just tapped mine in with a hard rubber mallet. I'm using a Comp cam as well. The way it came, it was a little too far out, but once I tapped it in, it was perfect.

 

I have to shorten mine too. Do you think it's safe to bang on the dowel pin while the cam's in the engine? What's behind the cam in there? Somethin solid?

 

I didn't do any precise measurements. Just used a tape measure and marked the pin with a marker.

The dremel tool with a cutting disc, cut right through in it about 10 seconds. It cut very easily.

I then took some emory cloth and sanded off the burrs.

I too was afraid of banging on the cam, so I lightly tapped on the pin and it didn't seem to move so I then just cut it off.

 

Do not hammer on the pin or the end of the cam.

If you must do it with the cam installed, the biggest danger is the grit and chips you make getting into the engine. Mask off the area like surgeons do before operating: just the portion of end of the cam exposed where the dowel fits. Plug the threaded holes to keep grit out, or tape over them.

I like the dremel cutoff disk idea. It'll give the least grit/chips. You could also use a vacuum cleaner while you are cutting to suck out the grit. I would.

You could wrap a 5/8 (.625) wide piece of tape around the dowel pin and use it as a cutting guide. A BAND-AID Junior strip is .625 wide, BTW. Clean the dowel with alcohol to degrease it first. If you slip with the Dremel you'll already have a bandage for the cut.


Definitely smooth off the sharp ends.

 

I would agree with your comments. The approach I mentioned above is with the cam out of the engine. I can't imagine someone installing a cam and then trying to get the dowel to the correct length. The procedure to shorten the dowel would be much more delicate/complicated with the cam in the engine.

 

Well Im going to do it with the cam in the car. Ill do what oldsstroker said and make sure everything is masked off good. Ill mark the cut line with some permanant marker and go at with my dremel.

Can you cut off too much? What I mean is that Im going to mark off .2" of an inch but If I get closer to .3" or so is that going to mess things up? Are .01ths critical here?

 

Are you in the middle of doing this now? Why not just get the pin to the desired length when the cam is out? Also I tapped mine in with a hammer & a piece of aluminum to the correct length. I see no problem with tapping it in as long as you use a piece of aluminum as the blunt. It does not take much effort. After all it is a Dowl Pin. Also don't the comp cams pins come longer for the vented opti's? I still have a non-vented opti which needs the dowl pin to match the stock cam so I needed to shorten it.

 

The cam is already in the motor. Its already degreed, etc and I dont see the need to tear down the whole front of the motor along with the intake etc just to grind down the dowel pin a little bit. The vented opti's need a .620 dowel pin. The pins come from comp .840" long...

 

Ahhh. Me stupid... I can't comprehend what I read. Sorry. I definately wouldn't tear the cam out either....


Also I wouldn't tap it in with a hammer either...... with the cam in the car...

 

i to had to grind while the cam was installed. i used a piece of old inner tube cut a small hole then turned a tube to fit the i.d. of the opti seal. pressed the tube in and used an angle grinder with a 3/4 sanding disc.if your not in a hurry send me your address and i'll send you the tube.
matt