| Ryan5895 |
Tue Apr 17, 2012 2:54 pm |
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I have a 1200 engine and I bought a set of dual springs to complement a cam I bought. So I put the springs on and they are ungodly tough (Bent my diesel spring compressor).
So my first question is: are 40 hp heads shorter between the valve spring seat and the tip of the valve than regular VW heads?
My second question is: Are the dual springs even necessary? I have an FK41 cam with .364 cam lift and with my 1.25 rockers I'm looking at .455 valve lift. I'd rather not run the springs unless its necessary. The redline I'm looking at would be about 5400 max but more likely 4000 because of the crank. |
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| sgmalt46 |
Tue Apr 17, 2012 3:42 pm |
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| don't think you need dual springs . single heavy duty's are enough. plus i think you normally need to cut the spring seats in the head for duals. ? probably why they where so hard to get on.anyway duals are over kill. |
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| Ryan5895 |
Tue Apr 17, 2012 4:12 pm |
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Thats kinda what I figured.. The FK41 is a seriously mild cam and with such a low redline I kinda figured duals were overkill
I put them on a test head I cut for duals so that isnt why they were so hard to get on... legit, I leaned on just one spring with my entire 200 pounds and it moved maybe .100-.150 |
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| slalombuggy |
Tue Apr 17, 2012 9:30 pm |
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HD single springs will be plenty. Whos duals were you using? Most aren't that bad until you get to the LS-1 Chevy style or K motion springs FYI my new springs are 385lbs over the nose, 250lbs at rest. I had to get the machine shop to put them on for me I bent our HD compressor......
brad |
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| Ryan5895 |
Thu Apr 19, 2012 1:57 pm |
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| I'm just using some engle duals. I've never worked with true racing springs before so I really had no clue whether or not 200 pounds was alot or not |
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| slalombuggy |
Thu Apr 19, 2012 2:19 pm |
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I ran Bugpack HD singles on my 1776 (39x32 valves) with a 110 and 1.25 with steel pushrods for 15 years. Saw 6000rpm lots autocrossing. No problems.
brad |
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| Busted Knuckles |
Tue May 01, 2012 6:31 am |
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Contact the cam manufacturer and ask for specs for seat and open pressure with your valve train components instead of guessing at what should be used,
I've seen over-sprung valves wear down the lobes on cams especially now that the extreme pressure additives are gone from most motor oils. |
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