I am doing the opti conversion on the 93Z that I am building. Originally I ordered the cam for a 93, what I didn't know at the time was you can't do the CSI/double roller conversion on a non vented opti because of the fact the opti is driven off the back of the cam gear. Now I am doing the opti conversion and am going to have to get a cam for a vented opti.

I have the webpage that shows the differences between the two cams but I still have a few questions.

How is the opt driven in a vented opti? Is is with the longer dowel pin or is it the splined hole in the cam or both?

I talked to brent today at TEA and asked him and he said it was driven off the dowl pin only. I think I caught him at a bad time because he wasn't makint much sense.

Thanks for any help.

Jason

 

There is no "spline" in the cam gear for the vented Opti. It is just a pilot hole. The Opti is driven only by the dowel pin.

 

Besides the dowel pin drive, The vented opti does have an oring'd shaft that protrudes through the timing gear and into a hole in the center of the face of the cam. It's really not part of the drive - I suppose you'd say it's a locator...

Anyway, Most aftermarket LT1 cams have the larger hole in the center, so they'll work with vented or non-vented setups (although you'll still need the correct dowel pin).

IMO - It would be worth your time to check and make sure your cam has the correct size hole in the face to work with the vented opti.

 

Thanks for the replies. It makes sense now. I miss read.