Crane Cam problem

[Big Woo]

This is regarding Crane Cams Mitsubishi 4G63 camshaft set P/N 435-0014 grind number MIT-264-25R-10
Intake duration 256 lift .443
Exhaust duration 245 lift .424

Has anyone run into a problem with the intake cam, where the slot cut into the back of the cam for the CAS (cam angle sensor) is too narrow for the CAS drive lug to fit? As I measure it, it is .011 smaller than the width of the drive lug. I din'nt bother trying to exchange the cam with Crane, I just modified the cam on the bridgport.

Having used just about all of the aftermarket cams available for the 4G63 over the years, this is my first time using the Crane Cams.

For others future reference this grind is a tight fit with 9:1 JE's and 1mm over valves. Both the block and haed were used but have never been previously cut/decked. I took .004 from the block, and ,006 from the head well within specification for clean up.

The JE's needed the exhaust valve eyelets releived a bit as the 1mm over exhaust valves tended hit the top edge of the eyelet. The intake side was fine.

With the valve grind done and all valves seats at identical depths within .005 as measured from the head surface initial piston to valve clearence was .044 on the intake side, and .038 on the exhaust. definently in the tweek zone. Since I could not cut enough from the JE pistons valve reliefs and still keep sufficient material between the bottom of the valve relief and the backside of the top compression ring groove (yes this gets very close on most four or five valve motors), I opted for a custom head gasket.

The folks at Cometic were very helpful and had a custome thickness version at my door in four days. (SBR could learn something here) I ended up with .104 on the intake and .098 on the exhaust.

I just thought I would share so others could bennifit.

 

[PieEyedPiper]

Good post.
Had you contacted Crane about the CAS issue? Just wondering what their comment would be.
Would you say it was a PITA to mod the cams to work?

 

[DoyoFCT]

I have heard about this problem before, so its definitely not a first. I also think other brand's have had similar issues. I'm sure they would exchange them out for you.

 

[Defiant]

the slot cut into the back of the cam for the CAS (cam angle sensor) is too narrow for the CAS drive lug to fit? As I measure it, it is .011 smaller than the width of the drive lug. I din'nt bother trying to exchange the cam with Crane, I just modified the cam on the bridgport.

Oo. Is that thin enough to not cut through the case hardening, or is that part of the cam not treated? I know the lobe faces are.

 

[Big Woo]

Case hardening generally penetrates about 1.5mm or 0.059 inches per side. I opened the slot about .018 or 0.009 per side, this made the final width of the slot consistaint with the plethora of old stock intake cams laying around the shop.

I did end up contacting Crane, and they did offer to replace the cam, however this was after I had cured the problem. I am happy with the decision I made, since shipping to and from Crane along with their turn around time would have added 10 to 14 days to the project.

I have used Crane's products many times over the years (this was just my first use of their Mitsubishi cams) and I have found thier products very good in general, and they have alwasy stood behind their products and workmenship. Most of this previous expierence (specific with Crane) has been with V-8 engines in the IMSA (to date myself) NDRA, W.O.O. and SCCA series.

To quote another wiseman's thread I just used the
"reley on ability" method