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  #31 (permalink)  
Old 01-10-2013, 12:35 PM
How fast is fast enough?
 
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Quote:
Originally Posted by flyingputz View Post
I don't mean to beat a dead horse, but here's my dilemma. I thought I had this ALL figured out. I've got the #906 vortec heads, Comp 26918 springs(recommended installed height 1.80") 787 retainers and +.050 locks. This gave me my necessary height and retainer to seal clearance, with NO machining. I don't like the idea of taking away that much material from the guides and seat, especially since the guide is ALSO the spring locator. I don't even know if ANY material can be taken away from seat to increase installed height? Now my rockers are contacting on many of the retainers. If I put the standard locks in place plenty of valve tip is available, however, that takes away my retainer to seal clearance AND increases my seat pressure to approx. 144 lbs. I feel my only option is +.100 longer valves. I will take up any extra height with -.050 locks OR shims. I know I'll have to keep the geometry correct at final assembly via pushrods. BTW, cam is 222-230 dur. .509/.528 lift @ .050 with 1.5 rockers. I'll be using Comp 1.52 rollers(self aligning). Screw in studs are already in place. As stated, I already have ALL these parts. Any thoughts or suggestions greatly appreciated.
your seat pressure is of little significance here, what is your open pressure? If you have enough clearance between your retainer and seal with standard locks at peak lift then your best solution (and the free one) is to just use standard locks. I'm betting the .050" difference on the compressed height and pressure of your spring isn't going to make a bit of difference (provided you have clearance).

I hate to say this but the $240 you just spent on valves was over nothing.

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  #32 (permalink)  
Old 01-10-2013, 01:34 PM
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You don't want to go deeper on the spring seats if you can help it, either.
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  #33 (permalink)  
Old 01-10-2013, 02:23 PM
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Quote:
Originally Posted by ap72 View Post
your seat pressure is of little significance here, what is your open pressure? If you have enough clearance between your retainer and seal with standard locks at peak lift then your best solution (and the free one) is to just use standard locks. I'm betting the .050" difference on the compressed height and pressure of your spring isn't going to make a bit of difference (provided you have clearance).

I hate to say this but the $240 you just spent on valves was over nothing.
The problem being discussed is:
The clearance between the self aligning rocker arm rails and the valve lock (aka, keepers). The + .050" locks does nothing to provide more clearance. The + .050" locks will lengthen the valve spring by .050", provide .050" clearance between the retainer and the valve seal and will reduce valve spring pressure. .050" x spring rate per inch.

The Manley SS valves for Vortec heads have .290" tips and will solve the problem of self aligning rocker arm to valve lock clearance. The .290" tips provide .040" clearance whereas the 1955-1995 SBC valves with .250" tips provide .000" clearance. Using 1955-1995 valves and self aligning rockers can toss the self aligning rocker arms off the valve stems, or worse.

When you are using self aligning rocker arms:
1. Must use valves with .290" tips.
2. Must avoid valve float at all costs.
3. Must use hydraulic lifters.
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  #34 (permalink)  
Old 01-10-2013, 02:40 PM
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Originally Posted by cobalt327 View Post
You don't want to go deeper on the spring seats if you can help it, either.
I didn't go any deeper, just opened 'em up tp 1.350" with Comp tool #4721. The 'updated' Comp 26918 beehives are 1.310 seat diameter and were binding in areas where seat had casting ridges. Like I said, I'll definitely go a different route on my next set of vortecs. This first set was quite a learning experience. Things would have been much easier had I chosen a cam with a little less lift.
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  #35 (permalink)  
Old 01-10-2013, 02:41 PM
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Spring pockets on Vortec heads:
1. Enlarge pockets to a maximum of .100" for valve springs that are 1.350" diameter.
2. Do not machine the spring pocket depth in order to increase valve spring assembled height.
3. In order to increase spring height, use + .050" locks and/or + .100" long valves.

If there is another way to use Vortec heads, please advise.
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  #36 (permalink)  
Old 01-10-2013, 02:48 PM
How fast is fast enough?
 
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Quote:
Originally Posted by MouseFink View Post
The problem being discussed is:
The clearance between the self aligning rocker arm rails and the valve lock (aka, keepers). The + .050" locks does nothing to provide more clearance. The + .050" locks will lengthen the valve spring by .050", provide .050" clearance between the retainer and the valve seal and will reduce valve spring pressure. .050" x spring rate per inch.

The Manley SS valves for Vortec heads have .290" tips and will solve the problem of self aligning rocker arm to valve lock clearance. The .290" tips provide .040" clearance whereas the 1955-1995 SBC valves with .250" tips provide .000" clearance. Using 1955-1995 valves and self aligning rockers can toss the self aligning rocker arms off the valve stems, or worse.

When you are using self aligning rocker arms:
1. Must use valves with .290" tips.
2. Must avoid valve float at all costs.
3. Must use hydraulic lifters.
He said retainers, not locks, and also mentioned there was no contact with stock locks instead of the .050". I was just going off of what the OP posted. If it were locks I'd just grind a little off the top of the locks, .050" isn't going to harm it.

And since when do you have to use a hydraulic cam with self aligning rockers? I never heard that one. I ask because I have a solid cam I will be running with stock self aligning rockers.
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  #37 (permalink)  
Old 01-10-2013, 03:21 PM
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I know exactly what the OP was "trying" to say. I have been there before. Sometimes people get locks and retainers confused as the OP did in this case.

You cannot set the lash using a feeler gauge with a solid lifter camshaft if you have self aligning rockers. The gauge will not fit between the rocker and the valve tip.

Self aligning rockers are difficult to use with Comp Cams 875 or 15850 short travel hydraulic lifters. Those lifters set a .005" pre-load. I am using CC 15850 lifters and can set them with a "flick of the wrist" without a feeler gauge which is 1/16" to 1/8" pre-load.
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  #38 (permalink)  
Old 01-10-2013, 03:32 PM
How fast is fast enough?
 
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Quote:
Originally Posted by MouseFink View Post
I know exactly what the OP was "trying" to say. I have been there before. Sometimes people get locks and retainers confused as the OP did in this case.

You cannot set the lash using a feeler gauge with a solid lifter camshaft if you have self aligning rockers. The gauge will not fit between the rocker and the valve tip.

Self aligning rockers are difficult to use with Comp Cams 875 or 15850 short travel hydraulic lifters. Those lifters set a .005" pre-load. I am using CC 15850 lifters and can set them with a "flick of the wrist" without a feeler gauge which is 1/16" to 1/8" pre-load.
just cut the tip of your feeler gauges down... a set is like $5?
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  #39 (permalink)  
Old 01-10-2013, 03:39 PM
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Southern engineering will not solve the problem. If it would I would grind my own camshafts with a wood rasp.

When using self aligning rockers, the rocker MUST be pre-loaded (in contact) with the valve tip at all times or the rocker arms will be tossed off the valve. That eliminates the use of a solid lifter camshaft that may set from .015" to .030" valve lash.
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  #40 (permalink)  
Old 01-10-2013, 03:47 PM
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[QUOTE=MouseFink;1633233]Southern engineering will not solve the problem. If it would I would grind my own camshafts with a wood rasp. ...........QUOTE]

Love it,we're rolling on the floor in laughter.

Bogie
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  #41 (permalink)  
Old 01-10-2013, 03:48 PM
How fast is fast enough?
 
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Quote:
Originally Posted by MouseFink View Post
Southern engineering will not solve the problem. If it would I would grind my own camshafts with a wood rasp.

When using self aligning rockers, the rocker MUST be pre-loaded (in contact) with the valve tip at all times or the rocker arms will be tossed off the valve. That eliminates the use of a solid lifter camshaft that may set from .015" to .030" valve lash.
hyd cams don't always have contact.

I'll let you know how it goes. I may be right, or I may be crazy.
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  #42 (permalink)  
Old 01-10-2013, 04:22 PM
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Hydraulic lifter valve train must always maintain contact between the valve tip, rocker arm, push rod, lifter and camshaft lobe. That is why they call it "pre-load". If pre-load (contact) is lost due to valve float, valve bounce or lifter loft, you can have possible destruction of the engine. High lift camshafts increase the possibility of valve float if the valve springs are not strong enough to maintain the pre-load. When you reach a certain spring load, you must switch to solid lifters and self aligning rockers are designed for mild camshafts with valve lifts less than .525".

A camshaft with more than .525" valve lift require valve springs with no less than 150 lb seat pressure and 350 lb. open pressure along with full roller rocker arms. IMO, that is too high for regular production hydraulic lifters. I used Comp Cams 15850 short travel restricted oiling lifters because my Comp Cams 26918 beehive valve springs were set up at 144 lb. seat pressure at 1.750" and 330 lb. open pressure at .500" valve lift. No valve train noise and no sign of valve float at 5,500 RPM.
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  #43 (permalink)  
Old 01-10-2013, 05:31 PM
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Quote:
Originally Posted by MouseFink View Post
Hydraulic lifter valve train must always maintain contact between the valve tip, rocker arm, push rod, lifter and camshaft lobe. That is why they call it "pre-load". If pre-load (contact) is lost due to valve float, valve bounce or lifter loft, you can have possible destruction of the engine. High lift camshafts increase the possibility of valve float if the valve springs are not strong enough to maintain the pre-load. When you reach a certain spring load, you must switch to solid lifters and self aligning rockers are designed for mild camshafts with valve lifts less than .525".

A camshaft with more than .525" valve lift require valve springs with no less than 150 lb seat pressure and 350 lb. open pressure along with full roller rocker arms. IMO, that is too high for regular production hydraulic lifters. I used Comp Cams 15850 short travel restricted oiling lifters because my Comp Cams 26918 beehive valve springs were set up at 144 lb. seat pressure at 1.750" and 330 lb. open pressure at .500" valve lift. No valve train noise and no sign of valve float at 5,500 RPM.
A hydraulic lifter is designed to always have preload- HOWEVER it does not mean it does in operation. Yes even in a bone stock application.
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  #44 (permalink)  
Old 01-10-2013, 06:06 PM
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There are guys doing it. Not saying it's right, just saying. Using a roller rocker w/the rocker sides 90 degrees to the roller/valve tip would seem to be a better idea than using stamped rockers.
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  #45 (permalink)  
Old 01-10-2013, 07:25 PM
How fast is fast enough?
 
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There are guys doing it. Not saying it's right, just saying. Using a roller rocker w/the rocker sides 90 degrees to the roller/valve tip would seem to be a better idea than using stamped rockers.
hey, look at that I agree entirely with this post!!!

Its not optimal, but it works. simmilar to how some would always use a 6-71 on an sbc, it may be from from optimal but in a pinch it works.
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