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That's not a Harbor Freight scale..can we trust it?
What brand/model spring is that? I suppose Ti retainers. What material are the locks? What's the spring weigh by itself? Need to get off my lazy butt and pull a BTR .660 and weigh that setup too.
That's not a Harbor Freight scale..can we trust it?
What brand/model spring is that? I suppose Ti retainers. What material are the locks? What's the spring weigh by itself? Need to get off my lazy butt and pull a BTR .660 and weigh that setup too.
The scale is legit. I use it to calculate bobweights and it's usually within a gram of what the scales at Scat, Wiseco/K1, and Callies say.
The spring is Comp's "new" conical spring (7228-16) with the OEM steel retainer and locks. I haven't weighed any of the springs by themselves.
Yea that's why i would stay away from cheaper springs like comp's.
I wouldn't call them cheaper, they were still like $250 for the springs alone. That's about the same for a lot of dual spring kits that even come with retainers, seats, seals, etc.
My problem was CREATED by CompCams "behive" springs and cam at Westech, a bench Dyno test.
My ECU-882C, my coils, turbo LS, Comp Valve Train, Comp "turbo" cam. (free)
The Spring broke in minutes, cam made no power BEFORE the spring cracked.
I called Carl Wegner, he stated "I have never broke a "behive" PSI 1511ML spring in ANY of the GNW engines we sell, they are required items."
The camshaft was replaced by a stock GM ZO-6 item.
The PSI-1511ML's where installed
The engine now ran fine, we made 1200+ HP@22 PSI.
Another item I will NEVER understand, why most install a TI Retainer on an exhaust valve when the weight, with a steel retainer, is still less than the intake with a Ti Retainer.
Another item I will NEVER understand, why most install a TI Retainer on an exhaust valve when the weight, with a steel retainer, is still less than the intake with a Ti Retainer.
Lance
I have always wondered the same thing. Technically you don't need quite as much spring, either; especially not with the smaller exhaust valve and Ti retainer. But like everything else it seems the market is based on sets of 16, 8, etc.. You can buy singles but it doesn't save much. I bet mfgs/vendors also don't want to depend on the end user to put the right stuff on the right valves. Put the lighter spring and/or heavier retainer on the (bigger/heavier)intake valve and things can get 'splodey.
Finally got off my butt to weigh some BTR parts. This is the BTR "Platinum" .660" lift kit (SK001) with titanium retainers. The locks are not titanium in this kit but steel(or some ferrous material but close enough)
BTR dual spring: 94g
Retainer: 9g
Locks: 3g
So the BTR duals weigh less than a 918 single?! No wonder we've been eating up the marketing of duals having no disadvantage(weight/power/RPM) compared to singles.
Again, the BTR .660s are fantastic.
But with the right setup, there is likely a place for a light-weight beehive.
YES, I do use different springs on Intake/Exhaust Valves.
I have used "duals" on intake ONLY for a SC engine requirement.
This method can allow for seat pressure (high) AND low nose pressure (Hyd Lifter).
I have used "solid" Intake Lifters/Hyd Exhaust on SC cams.
I would like to ADD, the cam lift/nose pressure amount can EXCEED the ability of the stock GM lifter to maintain "0" lash as RPM increased.
07-16-2016, 09:19 PM
