Hey all. I am building a 383 from a 96 Caprice (5.7L lt1 block) she is pretty much done. When the engine shop looked at the cam the dowl pin looked REALLY long for some reason. I brought in the cam that was in the motor (which had a vented opti by the way) and the pin on the cam from comp cams was LONGER. Now i know the non vented cams the pin is shorter, and the vented one is longer...whats the deal with this cam having a longer the stock pin for the vented opti? I saw this and had the engine shop pull the pin out of the new cam and put the old pin in from the original cam, was i correct in doing this? THanks...

 

the pins on cams by comp cams are usually longer and either need to be shortened or you have to swap your dowel pin in like you did. it def was the right choice so that you dont burn the opti out.

 

awsome, thanks.

 

As long as the pin isn't longer than ~.685" you should be ok.

 

Usually, on vented Opti's, guys like to run a double roller timing chain, therefore, the pin would have to be longer..Im sure there is another reason for that, but thats what i can think of, off hand.

 

Shoebox....The cam is in the motor, the cam retainer plate is on and so it the timing cover, etc.. etc... I am also using a coyles double roller chain. I will have the engine shop mesure the distance the pin is sticking out. I know it definitly isn't flush, it sticks out quite abit which looks fine, but i want to make sure so i dont tear up optis. What should the legnth of the lin be when everything is together for a vented opti?

 

Just called my engine shop and had them messure the pin. The pin sticks out .360 out of the cam gear when it is all assembled. Is that correct for a vented opti?

 

The total length it should stick out of the cam is .620 or so.... who knows what it is after the TC gear is on.

Bret

 

Yep, my stuff all says .620 out the front as well. I know just a smidgen longer and it will bottom out in the opti.

 

Assembled though, out the timing cam gear, its .360" is that ok? or will i eat up optis? I heard something that .375 was the MAX is can be out of the timing cam gear. Sound right guys?

 

Do a search I know both measurements were discussed about 6 months ago on this forum.

 

No way to tell with a cam gear other than a stock one. Use some clay on the back of the installed opti to see where the pin is coming to.