If you add 1.6 rockers to a stock engine. Does that advertantly change the duration of the cam?

 

It will shorten it slightly. It will also give a shorter ramp rate and ever so slightly less lift.

Stockers are 1.7

 

So say I got 1.8 or 1.85 rockers. Whatever they are. That will also change the duration?

 

why would you go DOWN in rocker ratio ???

 

Its not my question. Someone else asked me and I posted it. I realized the 1.6 was a mistake once I re-read it. I think he meant 1.8.

 

Apparently a larger ratio will add some more duration, lift, and if they have a roller tip will free up a bit more power there due to the lack of friction.

 

I concur ... they will also increase the ramp rate ever so slightly too.

Typically speaking, there are other places to yield better gains than rockers. If you want to make a difference on your valve train, I would go with some Ti retainers and keepers. Maybe a spring change, but if you go with a much bigger spring, better look at pushrods too.

 

the rockers will change the duration of the cam giving the stock cam an ever so slightly lope. as this is what happened when i did mine. gave it a whomp whomp whomp sound. i like it. sounds better than stock but you have to listen for it. i bought the comp cam roller rockers and it did free up a little horse power but the main reason i bought them is that i am planning on changing out the whole valve train to comp. springs, retainers, push rods, keepers, lifters, and of course a cam. 212/218, .522/.529 114lsa to be exact.