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| Dr Evil |
Jan 11 2009, 09:09 PM
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#1
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Send me your transmission! ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 23,041 Joined: 21-November 03 From: Loveland, OH 45140 Member No.: 1,372 Region Association: MidAtlantic Region
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About corvair heads:
I went to the machine shop on Fri to get my heads that were finally done now that I located the rare valve locks. Of course it could not be that easy. The machinist tells me that the springs are too tight. Understand that these heads originally had smaller springs on them as they were the older model. The spring pockets were widened for the later style springs. I am using standard size valves, retainers, and locks. Here are the numbers: Recommended - Installed spring height 1.660" - Closed tension 78-86# - Open spring height 1.260" - Open tension 170-180# Actual - Installed spring height 1.450" - Closed tension 130-140# - Open tension Just above 300# So you see a difference in height of .200 and almost 2x the closed tension. However, research has shown some interesting things. There are options for springs; stock, Iskey, and HP. The stock are known to be crap as they lose their tension and are unpredictable in such. Here are the interesting numbers regarding the 3 options: Stock: Closed- 100, open- 205, coil bind- .096 Iskey: Closed- 130, open- 230, bind- .379 HP: Closed- 140, open- 265, bind- .093 So, you can see that the stockers are not even as low as is prescribed in the service manual and the aftermarket ones are all where I am now at 130-140#. That is still more pressure than I want. Here are the questions: 1- I need valves that have an install height of 1.450 and allows for .400 movement. Looking at these parameters I shopped for springs, are these likely what I would need? http://www.compperformancegroupstores.com/...ory_Code=SPRNGC 2- Provided I have enough material in the seating surface, would it be a bad idea to have them mill .200 out of the pockets? The machinist is not wanting to do this, and I have a spare head we can inspect to see if it will work, but woudl it not be easier to find shorter springs? This is my first time getting deep into the valve spring thing so if I am missing something, let me know. I am thinking that finding shorter springs should be the best bet, though. |
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| orange914 |
Jan 11 2009, 09:20 PM
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#2
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http://5starmediaworks.com/index.html ![]() ![]() ![]() ![]() Group: Members Posts: 3,371 Joined: 26-March 05 From: Ceres, California Member No.: 3,818 Region Association: Northern California |
corvair (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/icon8.gif)
(IMG:style_emoticons/default/shades.gif) (IMG:style_emoticons/default/biggrin.gif) |
Dr Evil SOT: Valve spring woes Jan 11 2009, 09:09 PM
sixnotfour call john barnes ,206-365-3900 , 30 plus year, hp ... Jan 11 2009, 10:03 PM
Vacca Rabite Could you have custom springs made?
Since you have... Jan 12 2009, 09:33 AM
r_towle cutting the spring seat is a viable option.
It wil... Jan 12 2009, 09:58 AM
Dr Evil After removing the inner dampener and changing all... Jan 12 2009, 04:51 PM![]() ![]() |
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