As stated above, I'm hoping to put my motor back together soon and am considering going with the GM846 cam. My current cam shares the same duration at .050 (222/230) but the lift is slightly more with the 846 cam. .544/.56? to my current .533/.544. Will programming be necessary and how will the emissions be affected with the increase in lift?

 

is the lobe seperation angle different?

if not, i doubt you will need programming. you would deifnitely eek a few more horses out with it, but it's really not necesary. If you passed emissions with the cam you have now, you should pass with the new one.

just wondering, why swap cams if the two are so similar?

 

Yes the lsa is the same for both cams (112), my quest for the 11s seems to have stalled at 12.01. I'm hoping that the slightly larger cam will get me where I want to be without compromising emissions and streetability too much.

 

wouldnt a steeper set of rockers be cheaper and easier?

i think i would rather just throw some 1.7's in then do another cam swap, would offer the same duration just more lift.

just a thought

 

I already have a set of 1.6s. The motor isn't in the car which is why this would be the right time to do this. I'd be open to other cam suggestions though, I'm not necessarily married to this particular cam. I just have to be concerned about emissions and my current cam is what was prescribed by ARE when I ordered their package. I understand that duration has more of an affect on emissions which is why I'd like to go with more lift.

 

Well I was able to get my hands on a used 846 but now I need suggestions on timing components and oil pumps. I never had a problem with engine oiling with the factory pump but did have problems with the pickup moving around. Would a high volume pump be necessary or will a factory pump with a welded pickup suffice? Also, what kind of timing gear/chain would you guys suggest?