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Must remove inner valve spring for cam break-in, really?

Richard150MPH

Veteran Member
Must now remove inner valve springs for cam break-in, really?
There goes my schedule for getting my truck back together!
This will be slow to do, access to the heads is not great.
Pretty mild cam, Comp #12-230-2
.432/.444 gross lift on a 110 center.

Never had to go to such lengths before.
I know the newer oils are crap, but I did pay $21.00 for Lucas break-in additive.
The only brand available without having to wait another three days.

So it looks like I have to bring each piston to TDC, remove the inner spring, then reassemble, eight times. :(
Then run-in the cam before repeating the chore a second time to put the inner springs back. :( :(

And some folk think Lotus or Alfa Romeo engines are a pain!
 
Well #=!!, after reading the entire Comp Cams instruction sheet I do not need to worry over their non-existent warranty.
Not able to just drop a few hundred more dollars in order to have ONLY Comp components!
I think they may have just lost a customer.
Good thing I only plan to put one more SBC together.
Suppose I will contact Summit Racing about the spring rate of the heads I bought from them before final assembly. But they are not Race heads so I expect the springs should be fine.
 
If they aren't "race" heads, they shouldn't have dual springs. If they are duals, they're too heavy and that can cause premature failure and you've most likely found the reason you lost those 2 lifters/lobes.
 
Seems companies do not want us to be fully informed.
I looked up my heads, SUM-152123 to find the spring pressure to ensure compatability with the Comp cam.
Summit site says single spring and damper, but does not give spring pressure or rate.
So I will call Comp in the morning, and maybe Summit too, to verify what is correct.
Still fairly certain I lost the old cam due to incorrect lash and being too deaf to hear it.

BTW, not thrilled with the rocker to valve stem alignment of two valves on each head.
It is said these are DART castings.
If I ever build another SBC I am going to insist on adjustable guide plates at the least.
No way to adjust these.
 
If the heads you have are the Summit brand heads they are made by Dart so I'd look on Darts website for the spring rates and compare that to what summit and Dart say when you call them, I've never screwed with removing springs when breaking in a HFT cam but last 1 I did was 10 yrs ago and it was a Summit white box Crane 226/226 @ .050, .533/.533 lift, 108 lsa and broke it in on stock 22,4xx mile 454 with PP heads, then swapped heads and had retainer/guide contact, this BS soft metal they're make FT cams and lifters from is a joke unless you get a cam from someone like CamKing Mike Jones, Redline, Isky, but I'd never buy a Comp Cam
 
Comp guy says to verify the pushrods are spinning when I crank the engine over by hand.
If they are I will be fine, if not springs are too heavy and I still have to pull the inner damper springs.
Old lifters were evenly worn, not slotted.
 
Lot of people mistake damper for inner spring, Comp tech guy said PR should spin turning engine by hand? I cant see how that can happen? are the lifters still rounded or Convex on the bottoms? should be able to rock them on a pane of glass
 
New cam and lifters.
With all that lube I don't really expect the push rods to be spinning.
May be able to see the lifters turn when hand cranking?
Old lifters appear to have been rotating, the wear was even, not slotted.
 
Must now remove inner valve springs for cam break-in, really?
There goes my schedule for getting my truck back together!
This will be slow to do, access to the heads is not great.
Pretty mild cam, Comp #12-230-2
.432/.444 gross lift on a 110 center.

Never had to go to such lengths before.
I know the newer oils are crap, but I did pay $21.00 for Lucas break-in additive.
The only brand available without having to wait another three days.

So it looks like I have to bring each piston to TDC, remove the inner spring, then reassemble, eight times. :(
Then run-in the cam before repeating the chore a second time to put the inner springs back. :( :(

And some folk think Lotus or Alfa Romeo engines are a pain!
Would you like to do that job twice?
 
This was the second time around.
Crower stated that as long as the push rods rotate I will not have to remove the damper springs.
They spin, so I should be good to go.
Have about a hundred miles on it so far.
 
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