My current valvetrain has worked flawlessly over the last year, and some 50 or so 1/4mile passes. However as always I think there's more in there somewhere. I was going to switch to a 1.6:1 rocker ratio, and I'm not comfortable with using these springs at those lift levels. They may be fine, I'll have to pull one to be sure, but why not do a little more to control valve movement?

The beehive type springs sound like the "real" deal, and will help reduce a lot of weight at the valve end. The intended RPM range for this motor is under 7500rpm, currently limited to 7300rpm, and I have had no issue with the valvetrain (YET!).

Gross valve lift will be .608I/.6144E. Net valve lift with a tight lash will be .590I/.5944E. I think my current springs will work fine at this level, but be in the neighborhood of .060" until coil bind. Spring rate is ~186lbs on seat, and ~450lbs open. I am using Titanium retainers as well.

The argument implies less spring rate is required to control the valve due to the decreased mass of the valve side component.

That leads me to my question ( I have yet to consult Comp Cams about their product line ): What part number would be an equivalent match to my current springs, that would handle in excess of .600" of lift? Tall order I believe just from looking at what Summit has available.

Any input on these, or should I just get a bigger set of the standard springs and titanium retainers?

Thanks, any input is appreciated!

 

I have the same cam and have 1.6 rockers and use CC 929 double springs. I just had a quick look at the beehive spriings and I thought the selling point was the fact that they were a little smaller in diamter at the top and that makes it easier to clear rocker arms, I am sure you have seen the Crane Gold rockers clearanced for big springs. If you have no clearance probs I would go with the double springs probably cheaper. I will check to make sure that is the right spring number when I get home. Also when changing the rocker ratio be sure to check the pushrod does not rub the head as the higher ratio will bring the pushrod in closer to the head when the valve opens, and you might need to adjust the guide plates too

 

I've used two different springs on my low .600 lift solid rollers.

K-Motion 1100 1.550 dia 215 open max lift of .650 so i ran .050+ retainers. so it increases the max lift to .700 and dropped the closed pressure down to @195#

Great springs, but 195# is only needed for motors spinning over just over 8000 rpm with light valve train. I only need @ 175# seat and valve float would be near 8000 rpm even after some use where they loose a little pressure. So it's "Zero" valve float at my lower 7500 rev limiter cutoff.

This past spring I went with Comp Cams# from Summit racing "CCA-916-16" 1.554 diameter 200# seat and .700 max lift. I used the same +.050 retainers and the max lift is .750 It also brought the spring pressure down to @ 175# closed

 

i'm going to try a set on my 383 (hyd. roller)

 

Don't quote me COMP, but I've kind of heard that Hydro-Rollers top out about 155# seat pressure. after that your compressing the plugger. That's why H-rollers kind of have the low 6000 rpm natural rev limiter called valve float.

 

I don't know if the beehives have the same effect on GenI engines but the new 427LS is supposed to have a 7,000 rpm redline. In a recent HOTROD magazine article about the crate LS6 they found peak hp @ 6400 with the stock cam and at 6,600 with an after-market cam.

 

that's one reason why i want to try a set,, low weight ,also the retainer's.. less beating the seat's ... it's a test for me ,, the 3.0 Mitso. engine's used them yrs ago a quick rev. didn't hurt thing's

 

I run the CC 26918 models with CC R type lifters and a GM 847 camshaft (.575/.595 lift) to 6800 rpm with no valve float.

Prior to this I had issues with the REV 1122 springs including an AFR Hydra Rev kit at 6200+ rpm.

My pressures went down over the nose and on the seat as well as switched to a more durable steel retainer rather than the previous Ti one.

I'm sold on this type of spring...especially considering I stopped dyno testing at 6800 when looking back on it, I wish I would have pushed it to see how high I could have taken it...7200 or more???

I just looked at my notes...the Ti double spring retainer came in at 14 grams and the beehive steel retainer was 11 grams...