Thread: valve spring pressure

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I did a cam change on my 454 (bored .030" over) and ran into valve bounce at 5500 on the dyno. HP at 5500 was 483 and still climbing until bounce set in. I have a juice roller cam - Comp Cams 11-451-8 (230/236 @ .050", .547/.547" lift at valve, 112 deg lobe sep). I am using Comp Cams beehive springs #26120, which have been on the engine a couple of years.
Question is: I bought some .060" cups to go under these springs in the hopes that they will stiffen them up enough to allow another 300rpm or so. Will this work, and will the springs be more likely to fail with the decreased .060" installation height?
I have all the good parts in the rotating assembly to allow 6000+rpm (Manley H-beam rods, cross-drilled nitrided forged crank, forged pistons etc).
I just want to get near 6000rpm out of it - then I'm pretty sure I will have 500hp.
What other tips might anyone have for getting a few more revs - would shaft rockers do it? (kind of expensive!)
Thanks guys,
Chris

valve train weight is some thing you have to over come were a dual spring with or with out a damper i still feel is a better way to go?? then a single spring i know beehive is the way everyone is going but i feel a dual spring there some back up as well you bust one of you bee hives spring your down with busted parts 060 may not help. you want 135to145 on seat and open 350to 420 lbs would help i have had bbc go past that but with out a rev kit your starting to get at a point were the added weight is hurting you.if you still want your beehive look at 26120-16 should be good for590 lift you should get the set up of 1.880 .i was thinking we did talk about a rev kit last year ? Howards sell a rev kit for hyd roller lifters and now sell a pro max roller lifter 91171 for past 7000 rpm with 200-225 on the seat and 500-575 open then you can go past you cam grind if you go this way i would look at a steel core cam not a iron core if you go this way

what makes you think its valve bounce???

Thanks, Pat.
I currently have the beehives #26120 you suggested. As they were expensive (especially with the titanium retainers) I'd kind of like to stay with them. If there was a slightly stiffer beehive spring with the same diameters and installed height I wouldn't mind trying them.
Yes, you are right, you did suggest a rev kit, but I think the link-bar design of my Lunati roller lifters won't allow it. New roller-lifters would be expensive... Hell, maybe I should just get a new set of lightweight rollers that would allow a rev kit!!
Any recommendations??

Jerry, Peter Knight at Knight Racing who built up the engine seemed to know straight away what it was when the power suddenly stopped on the dyno at 5500rpm. They have a very good name over here and have built a lot of racing big-blocks for Can Am series etc, so I trust their know-how. He did try a couple of different ingnition settings, but things actually got worse when he did that.

juice roller cam----lifter pump up at that rpm???

did try a couple different ignition settings, but things actually got worse???? then its ignition and /or hydraulic lifter pump up

When I said "got worse" I meant less power.
You think it could be lifter pump-up? Do all hydraulic rollers do this at these revs, or can you recommend a brand/part # that will go past 5500??

there many roller lifters that i have used that went over 55000 .but why ?soild will go wayyyyyy past that .you should gear for TQ that cam is going to shut off much past 5500????

Well,

I have found some stronger beehives made by PAC Racing which are dimensionally similar to the CCA 26120 ones. They are PAC-1255 which are rated at 185 lb at installed height and about 410 lb at the 1.33" spring height at full lift of my cam. Old springs were 155 lb and 350 lb over the nose. Hopefully this will keep the valvetrain in check up to close to 6000 rprm.

My questions:

1:I'm hoping this pressure won't be too much for hydraulic roller lifters?

2:do I still need to shell out for titanium retainers (7.7 grams) or will I get away with the steel ones (12.3 grams)? Cam specs are on my first post.

3:I want to install the new springs without removing heads if possible. I have one of those gadgets for compressing the springs with the heads in situ. I believe that by plugging in a compressed air hose to the relevant spark plug hole this will be enough to hold the valves in that cylinder up hard enough to allow the springs to be removed. Has anyone done this, and does it work? What's the best procedure?

Thanks, guys.
Chris

yep i was looking at PAC springs made here in mich them springs are bit more .i would call who made the lifters thats getting up there but filled with oil the lifter should hold. do you have a steel core cam? thats alot for a iron core cam.i swap out springs that had 280 and 700 open on the engine

Pat,

it is a steel cam. The lifters are Lunati. So, I hope it's going to work. Steel or Titanium for the beehives' retainers, do you think?
What about the valve replacement with heads in place?
Chris

your talking a retainer smaller then 1 inch so some of the new ligth weight steel are not to bad .i did not look at the O.D of the retainers i have rework the retainers on the lathe many times . as for useing the tool and pumping air in the head i have done it many times .i used the cheap manley tool but the fork part may fall thru the smaller retainer .it is not that hard to do put air in the head the air will push the piston down tap the retainer with a ligth tap with a rubbber hammer to break the loose the valve locks .then use the tool to push the spring down. locks will now come out. then take tool off .you want a magnet on a stick that will help with locks . you want every thing at hand .when spring is off. i put the retainers with locks back on the valve with a test spring if i walk a way from the job .if some thing happens the valve will not drop down the bore .you need to know if the retainers are the same set up height if not your going to have to shim or use a + keepers to get them were they need.on the engine i would use a snap gauge/telescoping and a mic to check height

Pat,
that's a great help - many thanks!
Chris