What does your machinist mean by "they're fine" though? That they meet specifications for that type, or that they'll work fine with the quite aggressive E cam? Could be a big difference.
I don't think the open specs are out of line. But the difference in seat pressure is quite a bit. 90 to 120 is 33% or so, correct? That seems like a lot in the cam world.
I bet they'd work adequately for moderate playing around maybe. At least for awhile. Maybe I'm a mama's boy at heart, but spring selection is not one of the things I've ever second guessed the manufacturer on. I've always used the springs that the cam manufacturer recommended to get the most out of their cam.
I don't hold to their own brand always, but I do follow the recommendations for lbs.
And hopefully you're building a motor to snort around in and have some heavy right-footed fun? Those E303's have been the bane of Bronco owner's existence for about a decade now. Just too lopey and lumpy for most of us. On or off road.
But since you're building a stroker that might be able to take better advantage of it's characteristics, it might be right up your alley.
But I wanted to mention other member's feelings about it just in case.
Good luck with the spring selection. My vote is the better springs right off the bat.
Spending all the time, money and effort now and then dealing with a lower-then-expected rpm capability, erratic tuning from bouncing valves, prematurely fatigued, or broken springs because they weren't up to the task would be a pain. Hate to do it all over again.
Paul
