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grumpyvette · 12-10-2008, 11:09 AM

HEY GRUMPY?
I have some comp beehives on my bbc, part #26120
I also have a lunati voodoo hydro roller part # 60212
I have 1.72 ratio full roller rockers up top, I've cycled the engine through many times and checked clearance and have just a smidgen above .060 clearance in the middle.
This isnt a dedicated track car, just for street, and I dont plan on ever going above 5500rpm with it and have a rev limiter just to make sure, but does that amount of clearance with those parts seem safe enough to you? I don't think comp makes a stronger beehive for hydro rollers, and I dont feel like respending money, I've read many things and some people say you should have .100 clearance in the spring, and others say .060 is fine, what has been your experience?

I've called comp and they said they should be fine. However, I highly doubt they are going to reimburse me 8k in parts over their springs. I do want to protect my 8k I put in there, but at the same time dont feel like shelling out $250+ for new valve springs when the ones I have are brand new.

And I checked these clearances with no oil in the lifters whatsoever, they were completely bled down.

The people that assembled them for me http://www.m2race.com said on the install sheet that the installed height is 1.890, the installed pressure is 160lbs, and that coil bind is a .625 gross lift.

Comp says these are good to .600 lift and with the 1.72 ratio I come out to .607 lift. The tech on the phone told me it should be fine.
Would you run em?

ASSUMING your figures and info are correct,if your installed height is 1.890 and coil bind is at .625 thats 1.265 height for stacked spring coils, add .050 for minimal clearance and youll see a .575 MAX valve lift on the cam, BUT..

http://store.summitracing.com/partde...5&autoview=sku

http://store.summitracing.com/partde...2&autoview=sku

comp shows a 1.23 coil bind height, so given your lift is .607 the installed height and other clerances are critical to finding out if it will clear safely, 1.890-.607=.660-.050 for clearance =.610 so youll be ok IF the true installed height is really 1.890,
now heres what ID do,IF you want extra clearance just to be safe, ID install valve keepers/valve locks that gave me an extra .050 lift
http://www.cranecams.com/?show=brows...Number=99099-1
by seating the retainer .050 higher on the valve stem....since youve got no intention of running on the ragged edge of the rpm band, changing the installed height will lower the valve spring loads slightly but in your application thats almost a total non-issue, and yes it may require longer pushrods to get the rocker geometry correct so think thru your changes carefully.

12-10-2008, 11:09 AM	#3
grumpyvette retired mech engineer Join Date: Sep 2007 Location: florida Posts: 159 Name :	HEY GRUMPY? I have some comp beehives on my bbc, part #26120 I also have a lunati voodoo hydro roller part # 60212 I have 1.72 ratio full roller rockers up top, I've cycled the engine through many times and checked clearance and have just a smidgen above .060 clearance in the middle. This isnt a dedicated track car, just for street, and I dont plan on ever going above 5500rpm with it and have a rev limiter just to make sure, but does that amount of clearance with those parts seem safe enough to you? I don't think comp makes a stronger beehive for hydro rollers, and I dont feel like respending money, I've read many things and some people say you should have .100 clearance in the spring, and others say .060 is fine, what has been your experience? I've called comp and they said they should be fine. However, I highly doubt they are going to reimburse me 8k in parts over their springs. I do want to protect my 8k I put in there, but at the same time dont feel like shelling out $250+ for new valve springs when the ones I have are brand new. And I checked these clearances with no oil in the lifters whatsoever, they were completely bled down. The people that assembled them for me http://www.m2race.com said on the install sheet that the installed height is 1.890, the installed pressure is 160lbs, and that coil bind is a .625 gross lift. Comp says these are good to .600 lift and with the 1.72 ratio I come out to .607 lift. The tech on the phone told me it should be fine. Would you run em? ASSUMING your figures and info are correct,if your installed height is 1.890 and coil bind is at .625 thats 1.265 height for stacked spring coils, add .050 for minimal clearance and youll see a .575 MAX valve lift on the cam, BUT.. http://store.summitracing.com/partde...5&autoview=sku http://store.summitracing.com/partde...2&autoview=sku comp shows a 1.23 coil bind height, so given your lift is .607 the installed height and other clerances are critical to finding out if it will clear safely, 1.890-.607=.660-.050 for clearance =.610 so youll be ok IF the true installed height is really 1.890, now heres what ID do,IF you want extra clearance just to be safe, ID install valve keepers/valve locks that gave me an extra .050 lift http://www.cranecams.com/?show=brows...Number=99099-1 by seating the retainer .050 higher on the valve stem....since youve got no intention of running on the ragged edge of the rpm band, changing the installed height will lower the valve spring loads slightly but in your application thats almost a total non-issue, and yes it may require longer pushrods to get the rocker geometry correct so think thru your changes carefully.