 Valve geometry hell |
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| malcolm2 |
 Jun 25 2020, 09:19 PM
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#1
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Advanced Member  Group: Members Posts: 2,749 Joined: 31-May 11 From: Nashville Member No.: 13,139 Region Association: South East States 
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Help me out here. Working on the subject and can’t figure it out.
9590 cam. 0.426 lift on the card. Adjustable pushrod tool. I get to 0.426 lift. But the geometry between the swivel foot and the valve is wack. That is shortening the PR. Stretch out the PR and i get 0.430 lift and almost straight valve to adjuster. The foot is too tight to the 1.7 rocker boss. Bought some shims to lift the rocker stand and try that. Question is: why am I so far off the card lift? Does it matter? |
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| Jake Raby |
Jul 4 2020, 06:24 PM
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
With the 9590 you should dial in around a 27.1cm pushrod on the intake, to net .434” lift~
The exhaust side will usually never net more than .410” lift due to the rockers. Typically the pushrod on the exhaust side will run around 27.0Cm in length to net the most lift. These are examples, but usually pretty close. There’s 11 variables that play into this, the biggest being flycut depth and cylinder shim figures. I have taken up to .080” off of rockers, then lightened the 35 grams, with no issues. Those were for the 2563cc in my 356C, which has been together since 1999 and I haven’t broken a rocker yet.. |
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Posts in this topic
malcolm2 Valve geometry hell Jun 25 2020, 09:19 PM
wndsrfr
Help me out here. Working on the subject and can... Jun 26 2020, 05:53 AM Olympic 914 When using the swivel foot on the 1.7 rocker arms ... Jun 26 2020, 06:03 AM malcolm2 I do plan on removing material. Is it about 0.060... Jun 26 2020, 06:23 AM nditiz1 I had my rockers milled, but I can't remember ... Jun 26 2020, 07:15 AM 914werke RE: Valve geometry hell Jun 26 2020, 08:33 AM Mark Henry Don't worry about the lift vs the card.
Inste... Jun 26 2020, 09:49 AM
malcolm2
Don't worry about the lift vs the card.
Inst... Jun 26 2020, 09:55 AM Mark Henry
[quote name='Mark Henry' post='2828271' date='Jun... Jun 26 2020, 11:03 AM malcolm2 The counter sink is a nice touch. great picture. ... Jun 26 2020, 09:49 AM malcolm2 Thanks for the input. Heads are camper specials. Jun 26 2020, 11:35 AM malcolm2 I have removed about 0.060”. There is no way i a... Jun 29 2020, 05:05 PM wndsrfr
I have removed about 0.060”. There is no way i ... Jun 29 2020, 09:19 PM Highland I used this guy and he seemed to do a good job.
h... Jun 29 2020, 11:14 PM BeatNavy
I used this guy and he seemed to do a good job.
... Jun 30 2020, 04:27 AM nditiz1
[quote name='Highland' post='2829452' date='Jun 3... Jun 30 2020, 06:44 AM TheCabinetmaker My 9550 Cam, .426 lift ended up at 436. Bonus... Jun 30 2020, 04:48 AM malcolm2 Len and i talked about other machine work. IIRC he... Jun 30 2020, 07:53 AM |
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