So you guys know my issues with the Hemi eating intake valve springs....Who's springs should I go with on this rebuild for just over .700" lift?

Remember, this is street/strip application.....I can post the new cam specs later when I get home.

IMO the best are PSI springs with Xceldyne locks/retainers.

I second this

I have nothing but good things to say about Pac. Never broke any. They've showed zero loss in pressure on the two sets I replaced just on maintenance. Everything in the valve train is happy. Close to 600 passes on the lifters. Valve seats stay nice.
Doug

PAC here too.....Springs on my engine have been run 3 years with heavy stainless valves and hundreds of passes and yet to see any pressure loss.

PSI

My first thought was, are they suffering from too much heat, not enough oil cooling? No spring will hold up well if it gets too hot. Figure that out and you might find it isn't your choice of springs so much as the heat.
What springs are you running? Are they up to the task?

This is by George Bryce, its about motorcycles but it applies to car heads also, good info,

https://youtu.be/9KvRBzKjCho?list=PLB2-V7-On60DG44XrHYCVcjnL2yAoCUa2

PSI, or the Isky toolroom premium stuff, depending on the requirements. S/F....Ken M

My Dad and I have used comp endurance springs in my 418". The original camshaft in 2015 used the same springs until this summer when we changed cams. 7 years and 3 drag weeks with no problem at .650ish of lift at the retainer. 80% of drag week for me is 3000-3500RPM cruise.

If you haven't I would have someone spec a camshaft that knows you plan to drive it on the street. What little you may lose in performance you will likely gain in longevity. My first camshaft mentioned above used lobes that comp normally uses for circle track stuff. The current camshaft was lobes from the "Low shock" line that is supposed to be softer on the valvetrain. The new cam only has one drag week on it, and that may be its last as its actually a little slower lol, still some things to try before we take it out though.

That all being said my old 360 had 4 drag weeks on it with some random Reed grind .650(on the card) solid roller. I used $100 K motion K800 springs and changed them every year before drag week. I never hurt one of those springs either but they were cheap enough I never ran them more than one season.

For street/strip endurance applications, Isky Tool room or Manley Nextek springs.

AG.

All of the higher end Isky springs are PAC-alloy or PSI. I have never seen either break. I have seen them turn blue from heat but never fractured. I have a set of PAC springs that came off of a 540 Hemi with a +.700 lift solid roller. The owner wanted a smaller cam after the first few dyno pulls lol.

What are the OD and IH of the springs you are currenty using? I have the matching retainers also (stage V heads).

PAC springs on my hemi.

@Dragula - check your PMs

Sorry, forgot to post cam specs.....I will get to it tonight...

I believe Dwayne set you and me up with the same PAC 1243 springs, but I have no experience using them at this point

I don't know how aggressive the cam is or what the manufacturer suggests for springs but you might be able to run the same ones I use.

PSI 1575ML

With .710 lift it would be-

1.86 installed 228lbs

1.15 open 625lbs


1.4 diameter of the above saves a lot of weight over the 1.55 stuff.

Would say you need to measure actual lift rather than base the installed height on theoretical lift if you haven't already done so.

I think the strongest pushrods that fit is very important as well.

Yes he did. I'm on my 3rd set of them since 2006. I just changed them out when I freshened it up. They still pressure checked good both times.

I prefer PAC sprinmgs myself. Always given me great service life, we run them on the heads up car as well. So cant say never broke one but 10,000+ rpm can do that

PAC on my Hemi and 440 Sixpack. We use thousands of sets od PAC and PSI with no major issues with either.