End stands required?

[matt souders]

A couple questionns. First I'm going to be running the xe 274 cam on either comps 924 springs or on a set of Howard's springs the comp springs are 112 seat and 303 open pressure and the Howard's are 110 seat and 315 open. With this sit up are end stands for the rocket shafts required? And the second question is which springs would you guys prefer?

[Ranch]

My experience
   No. but you should be concerned about your heads being preped for that lift (.565). I use to run up to 7K with OEM shafts and stands with the old solids "B" cam (.500) and No problem.  If you have any concerns, you might want to get the beefier shafts from Doug @ "Precision Oil Pump" (your shafts might be a little worn). I like to run my oil tins and it's hard to fit them with an after market valve assembly.
Springs... Go with what is recommended by Comp, it all work together. Usually it's cheaper when you buy the whole package....JMO... Hope it helps

[rcodecj]

My old Crane cam had .542 lift with no problems.
My buddy's Crane cam had .580 lift and he snapped shafts.
It isn't all about lift though, with an XE cam that has more aggressive lobes, higher valve spring pressures and more lift, the end stands would be good to have.
I wouldn't run without end stands anymore, just wouldn't.

[fastback 427]

I'd run the end stands as well. I've snapped a couple shafts myself with a .569 lift cam as well. Lots of flexing on that shaft hangin out there.

[chris_r]

+2 on dove or doug h-d shafts and you are good to good

[matt souders]

I guess my question about springs is more about which brand would you trust more for reliability.  Comp recommends the 924 spring and that's what I have. I also have the Howard's cam springs that are very similar just a tad stiffer. I recently heard that comp springs have questionable reliability. I'm not saying that it's true I just don't know. The Howard's stuff I have zero experience with and just got the springs with a set of heads I purchased so if I'd use them I'll have to take me to my machine shop and verify the pressures, because of there unknown history.

[CaptCobrajet]

I would invest in HD shafts, and studs.  Also measure all of the stands and make sure the shafts will be straight and not bending when torqued.  With that kind of cam and spring load, good fasteners, good shafts, and a mill or surface plate to tweak the stands all the same will be just fine.

[Joe-JDC]

The seat pressure is low in my opinion.  I don't think you will be able to control valve float with that much lift and only 112# seat pressure.  I personally would like to see at least 135# seat pressure at correct installed height for any FE intake valve, and the larger the valve, the more seat pressure needed.  Joe-JDC

[chilly460]

My rocker shafts showed signs of flexing on the outboard ends with a little 270H Comp, shifted at 5500.  I think the more aggressive ramps on modern (not that the 270H is modern, but it's more aggressive than 60s tech) cams is the culprit.  Good peace of mind to go with captured stands or thick shafts. 

[matt souders]

I know you said correct installed hieght but if you have the clearance and no coil bind what's the down side of lowering the installed hieght to achieve the pressures you recommended. I'm just trying to understand not argue. Lowering the installed hieght to 1.85 on the 924 springs will get me close to your recommended pressures. That's .05 lower than the advertised installed hieght. If you tell me that's not a good idea I won't do it just asking.

[CaptCobrajet]

You just need to make sure about the coil bind height.  As long as you stay .060 from coil bind, you can shim or use -.050 locks to shorten the spring height.  I think 310 open pressure will be fine with that cam.  Seat pressure is not as critical as the nose pressure.  If you push a "driver" flat lifter too far, you start to run the risk of lobe failure.  I like to overdo it on valve spring with rollers or Shubecks, but a street flat lifter is a place I might lean toward using the minimum. JMO.