1.7 Rockers with E303 cam???

Discussion in 'Fox 5.0 Mustang Tech' started by jimilane, Aug 13, 2005.

  1. I have a set of 1.7 roller rockers.
    The stamped rockers on one head are worn and need replacing.

    You guys think the stock (NEW) springs will hold up to the extra lift...somewhere around .530 lift???

    Well.....I think probably not.....but is anyone running an E303 with 1.7s on stock heads with stock springs...??

  2. If you like valve float and spring binding, GO FOR IT!!! :nice: :p
  3. I didn't think it would be a good idea. But I wanted to see if anyone had tried it. I bet it wouldn't idle very well. But I wonder how close the vavles are getting to the pistons...???

    I'm going to get some 1.6 roller rockers Monday.

    I put some stock rockers off another engine on tomight thought. I got rid of most of the problems. Just one rocker is ticking now.

    It seems that if a set of rockers gets worn in with the stock cam pretty good...changing the cam to an E303 makes the valves run on different parts of the rocker...then there is a little ridge and the rockers will tick.

    Amazing find...
  4. I'm running an E303 in mine, and I have a set of 289 heads on it. I would definitely recommend heavy duty valve springs. I have double springs, and I had to get some good roller rockers because I was breaking the stock rockers in half.
  5. i am running a E303 cam and the Cobra energizers 1.7 roller rockers and heavy duty springs from Crane Cams, and the stang is running strong, no valve floating and i have flat top pistons too and there is enough clearance to run the cam and roller rockers :flag:
  6. That's interesting.......where were the rockers breaking exactly. Were they cracking at the bottom where the pivot is? I just want to know where to look.
    I have the stock spring on there right now, so cracking one might not happen to me right now, but I guess I might have to put some more stuff on the engine it looks like.

    Thanks for the INFO!!!

  7. You are going to want better than stock springs even with the 1.6 ratio and the E-Cam.
  8. Im running crane 1.7rr's and the e-303 with stock springs. Have had this for more than a year and seems to be working fine.
  9. !

    I'm running GT40 heads with the springs that came on them, with E303 cam and Cobra 1.7rr :D Car runs good. I also have a stock bottom end.
  10. ive got a 91 lx non roller 302 ive got a 520 lift cam in it along with 289 heads that have been shaved 14 thousands i am wanting to run 1.7 roller rockers will it work or do i need to stick with my 1.6
  11. I swapped 1.6 for 1.7 comp roller tip rockers, and could not tell any difference at all. plus I had to get longer pushrods to get the rocker centered on the valve. I ended up putting the stock 1.6's back on.