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Finished clearancing one of the heads for the pushrods.

IMGP2647rs.jpg
 
I got the impression from Dave that you want full flow and pressure to the lifters. The oil holes (there are two) in the lifters that feed the pushrods are clearance fed. The pushrod feed holes are about 180 degrees from each other, slightly above the large machined groove around the middle of the body of the lifter. There is no trench machined into the body from the large groove around the middle of the body to these holes. The holes are truly clearance fed.

The roller bushing is fed through a small EDM hole that opens into the deep machined groove around the middle of the lifter body, and sees full galley pressure. I'll try to post a picture tonight.

edited: July 26th, 2012
I edited this particular post after finding out that the roller bushing is getting oil through a small .024" hole in the lifter body that is seeing full galley oil pressure. HIPPO (High-Pressure Pin Oiler)
 
I edited this particular post after finding out that the roller bushing is getting oil through a small .024" hole in the lifter body that is seeing full galley oil pressure. HIPPO (High-Pressure Pin Oiler)

Thats how mine are.
Allan G.
 
I got a spring recommendation from Crower.
Dual spring w/damper
O.D./I.D. Outer: 1.615/1.175"
O.D./I.D. Inner: 1.060/.775"
Installed height: 2.100"
Spring rate: 530 lbs/in
Part #68755
Color code: Gold
Free length: 2.665"
Wire dia: .225/.147"
Material: Super Clean Silicone
Coil bind: 1.190"
Retainer: 10 degree Ti

Pressures;
Seat @ installed height (2.100"): 287 lbs
At .700" lift (1.400" spring height): 671 lbs

This is for a rpm limit of 8,000 with stainless valves, 9,300 rpm with Ti valves.
Max lift: .700"

I did email them back to remind them this would be a 40-45 psi boost application. I haven't heard anything back, yet.
 
Same spring as above installed at 2.050";
Seat pressure: 312 lbs
Open at .700" lift: 706 lbs

Same spring as above installed at 2.000";
Seat pressure: 336 lbs
Open at .700" lift: 738 lbs.
 
Your old engine had o-ringed heads and matching grooved sleeves, doing that again with this setup?
 
Way too much pressure for me........but it may not be enough for 9000 rpm?@boost?
 
Way too much pressure for me........but it may not be enough for 9000 rpm?@boost?
I don't know. :confused: Seems to fall in the right range for a .700" lift, from what I've come across so far.

The heads have been clearanced for the pushrods. The length I'll need looks to be 9.400".
I'm debating whether to go with 5/16 to 3/8 single taper, or 3/8 to 7/16 single taper. The seats of the lifters will fit a 7/16 end (5/16 ball end), even with the offset. The 5/16 to 3/8 pushrod would be lighter.
 
I don't know. :confused: Seems to fall in the right range for a .700" lift, from what I've come across so far.

The heads have been clearanced for the pushrods. The length I'll need looks to be 9.400".
I'm debating whether to go with 5/16 to 3/8 single taper, or 3/8 to 7/16 single taper. The seats of the lifters will fit a 7/16 end (5/16 ball end), even with the offset. The 5/16 to 3/8 pushrod would be lighter.
Push rod size is not an area to be looking at in saving weight in this app.
 
Push rod size is not an area to be looking at in saving weight in this app.
I hear ya. I just don't want to run more pushrod than I actually need. My Stage I motor had 3/8 to 7/16 single taper pushrods, and those suckers are heavy.

Here's an interesting link that explains well the theory of valve spring requirements on a boosted motor.
http://www.magnumpowers.com/light_spring.php
 
The rocker arm geometry has been checked. It looks very good. The rocker arm roller starts inside of the middle on the tip of the valve stem with the valve closed. Moves to the middle at half lift (.350"). Rolls ever so slighty out of the middle as the valve continues to open, then ends up in the middle again at full lift.
 
Here are some comparison pics of a typical 5/16 pushrod and a 3/8 to 7/16 single taper pushrod with 5/16 ball ends.

IMGP2651rs.jpg
IMGP2652rs.jpg
IMGP2655rs.jpg
 
Here's some pics of the old Stage I head gaskets.
The thickness: .065"

IMGP2660rs.jpg
IMGP2656rs.jpg
 
It's interesting to see that one side of the gasket is showing more heat than the other side. The hotter side being the wire side.
If you know which side of a gasket is going to develop more heat than the other, where would you put the hotter side? Against the block? Against the head? Against the thicker deck surface? Against the thinner deck surface where the coolant is could carry the heat away quicker?
 
With a naturally aspirated Stage II Buick V6, Jim Ruggles suggests using a seat pressure of 220 lbs. for a 9200 rpm redline using titanium valves. How much more seat pressure would be needed in a blown application? I get the impression that you need to run 1 additional psi seat pressure to 1 additional psi of boost pressure, or exhaust backpressure. Whichever is higher.
It looks like Jim used straight 3/8" dia pushrods. I'm going with the 3/8 to 7/16 single taper pushrods again. I'm a firm believer in the theory behind tapered pushrods.

edit: The pressure differential across the valve as it's closing, multiplied by the area of the valve is the key.
 
When they figure in lash and deflection, did they have a range from coil bind that they recommend? I've been told .040-.080.
 
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