I have access to a decent deal on a set of low mileage 317 heads. My 5.3 currently has the 706 heads, all stock. Was contemplating on swapping to the 317 heads because I had heard they were better for F/I motors.

Can anyone tell me the pros/cons of running these heads on a F/I 5.3? Is there anything basic that should be done to them prior to slapping them on?

Thanks in advance for the info. I searched on here for awhile and could not find anything specific to this application.

 

The 317's will out flow your heads, but you will lose some comp by just slapping them on. Which is good and bad.. you could get away with more boost with the 317's... BTW how did you make on on getting a Y pipe

 

so there is no real benefit for me to run these other than better flow? I really don't want to boost more than 8-9psi.

As far as the Y-pipe, my truck is at the shop now getting the headers on and a 3" y-pipe fabbed up. They ran a tad behind getting the 3" piping to snake through, but its all tacked up and getting TIG'd up Monday for delivery.

I bought a Dynomax Bullet to reduce the rasp, but ended up not using it because I did not want to hack up the stock 3" Corsa mid-pipe. I am either going to have a new mid-pipe fabbed up with the dynomax installed or run an option from one of the members on here.