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Just need a baseline to start... 580-610 lift solid flat tappet crane gold 1.7 rockers. Don't want to pull engine to get numbers off the cam (if it even has any) checked them while repairing other custom parts (see below) intakes went from 10-21 exhaust more consistent at 21-23 I'm thinking 16 intake 22 exhaust comments welcome I'm an Oldsmobile guy not used to these fancy parts in BBC :))eek:))

 

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Just need a baseline to start... 580-610 lift solid flat tappet crane gold 1.7 rockers. Don't want to pull engine to get numbers off the cam (if it even has any) checked them while repairing other custom parts (see below) intakes went from 10-21 exhaust more consistent at 21-23 I'm thinking 16 intake 22 exhaust comments welcome I'm an Oldsmobile guy not used to these fancy parts in BBC :))eek:))
I would make note of the tight ones, and make sure to check them the next time you run it.

My own personal guess on an unknown solid flat tappet setting would be .022"/.024".. .002" extra clearance on the exhaust valves.
 

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You might want to do a leak down on the cyl that bent the pushrod just to be safe. you also may want to be sure the flat side of the roller rockers are facing up :))THumbsUp
 

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Ramp speed....

Valve "lash" is a recommended setting of the cam manufacturer based on ramp speed... Some cams are slower than others and require less clearance to maintain the designed duration of the camshaft... Others are fast, and require more. An old school idea says that loose lash gives you more bottom end, and tighter lash gives you top end, and additional RPMs. (not a lot, but some).... A mere .002 tighter MAY give you 200 RPM up top by increasing the duration of the "valve event". The lift isn't changed enough to matter.... The .018-.028 settings mentioned are certainly close enough to run with just about any solid grind, and from there some close monitoring and a little experimentation will allow you dial it right in to your application..... If it's a monster down low and noses over up top, try tightening in .002 increments until you balance out your performance for the best of both worlds.... I set valves cold, and if I need to check hot I'm only looking for consistency throughout the valve train...Which will also tell me where, (.xxx), my cold setting is when hot.... IMO, the best thing you can do for a solid cam application is a quality stud girdle to keep things where YOU put them.....
Ray
 

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Well....

When setting cold add .002 for iron block, iron heads
Subtract .006 for iron block, aluminum heads
Running a MK IV block, AFR aluminum heads, and a "Bullet/Straub" roller cam, I set the valves @TDC to the recommended clearances cold.... After a few runs for tuning I re checked hot and nothing had changed, well maybe a thou here or there, but nothing that couldn't be related to the new valve train parts finding their "home"..... I'm betting if I set them -.006 there would have a whole bunch too much overlap.....Not to mention the additional duration... Vacuum is a precious thing in a NA application..
Ray
 

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Well I'm going to go ahead and pull it. See if there's any numbers on it. Its only 8 bolts. Should change the oil and flush the sparklies out. Shop owes me a dyno run anyway.
 

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Running a MK IV block, AFR aluminum heads, and a "Bullet/Straub" roller cam, I set the valves @TDC to the recommended clearances cold.... After a few runs for tuning I re checked hot and nothing had changed, well maybe a thou here or there, but nothing that couldn't be related to the new valve train parts finding their "home"..... I'm betting if I set them -.006 there would have a whole bunch too much overlap.....Not to mention the additional duration... Vacuum is a precious thing in a NA application..
Ray
I too have set my lash cold..I belive the moter cools faster than I can move
Joey Grose told me ..solid roller .016 cold int. + ext.
I do .018 seems to be fine............the jesels dont really move to much
 

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Mine is a cast iron block, Brodix aluminum heads, comp billet roller, ....... Brodix says to set valves -4 from the .028/.030 advertised I set them at .024/.026 and checked after bring the motor up to 140* ....... they were .028/.030
 

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I don't know Jim. .000 to +.002 with iron heads is not unusual at all, and I subtract .006 my alumn heads. Maybe running gas and longer periods is the reason. All I know is that -.006 works the best for me.

As for medication, I saw your PS driver tonight. Now thats medicated ...Yea Dale is a real trip but he can drive, Rob drives too but he is still learning., and also me ofcourse.And now my Cousin Jody with the SE When Dale and Jody get together I don't know who is worse, Hope you had a good time there I didn't make it there this year maybe next year.
 

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Sorry jimbo, but those numbers are not mine. Taken off the Crane Cam website. Guess you better give those guys a call and straighten them out ???
Maybe I better, But I don't run crane cams either, I run Crower cams and Alky engines, My rockers don't move anything like that. Maybe .002 or .003 max,
 
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