datsunwizard Posted May 25, 2011 Report Share Posted May 25, 2011 But that is with the valve off of the seat, look at the picture. That picture is for checking for guide wear. I looked for that measurement in my old stuff, but didn't come up anything. What I use to do, is place a straight edge across all of the valve stems, with the straight edge parallel to the head surface to see what stems were long or short. Remember what you are trying to accomplish, is to have all of the stems the same length. Quote Link to comment
Sealik Posted May 25, 2011 Author Report Share Posted May 25, 2011 But that is with the valve off of the seat, look at the picture. That picture is for checking for guide wear. I looked for that measurement in my old stuff, but didn't come up anything. What I use to do, is place a straight edge across all of the valve stems, with the straight edge parallel to the head surface to see what stems were long or short. Remember what you are trying to accomplish, is to have all of the stems the same length. Ya...you're right it's off the seat. Quote Link to comment
Sealik Posted May 25, 2011 Author Report Share Posted May 25, 2011 But that is with the valve off of the seat, look at the picture. That picture is for checking for guide wear. I looked for that measurement in my old stuff, but didn't come up anything. What I use to do, is place a straight edge across all of the valve stems, with the straight edge parallel to the head surface to see what stems were long or short. Remember what you are trying to accomplish, is to have all of the stems the same length. With a straight edge....they are all at different heights. So....if I knew which one was the correct height (if any..lol), the machinist can go from there. Quote Link to comment
banzai510(hainz) Posted May 25, 2011 Report Share Posted May 25, 2011 Datzenwizard is spot on . when I was new to the L motor I had the first head done and it was a rinky dink place. But I had to question the machinst how he did the head. I asked and the machinist showed me how he measure the valve stem height. I told him I needed to use the same lash pad size with in hopefully .010Like having a straight edge across all the valves would be perfect. He stuck a valve in and had a dialgauge on the other side so I can see how much it pushed thru. Then when i did the rest at home it came out OK. I have a spare head now that Im looking at redoing. I know the # 3 exhaust is sunk were Im out of valve lash. So do I risk a new valve seat(as they can still come out ) or use another head that I know is better on the rocker arms lash/valve seat height and just do a basic regrind. then put a new cam in that. So I guess maybe you could have started with a better head. better machinist ect... to prevent some of this. The earlier heads could have more sunken valve seats till the later unleaded heads came along or if they were really but think maybe those are intakes have softer seats cant remeber. Unfortually you are learning the hard way, and costing you $$$ Then find out a Weber DGV with this cam isnt going to be neckbreaking. As sidedrafts really wake up a motor with a cam. But youll notice hopefully a different and once running youll feel good what you have done and can put other carbs on later. But thinking you have a truck a downdraft is best for the lowend up in the mountains Quote Link to comment
datsunwizard Posted May 25, 2011 Report Share Posted May 25, 2011 With a straight edge....they are all at different heights. So....if I knew which one was the correct height (if any..lol), the machinist can go from there. So "The Machinist" really screwed up then. Ok, It really doesn't matter what the actual height is, yet me put it another way. Which one of the stems gives you the best pattern, the best support for the lash pads with what you have for retainers and lash pads. Use that for the measurement, I would tend to try use the shorter one if the works out with the retainers and lash pads. Don't use the longest one, because that implies that you would have to sink the the valves, which hurts flow and lowers the compression. The seats will have to be replaced on the ones that are too long, because they where over-cut or from wear. Quote Link to comment
datsunwizard Posted May 25, 2011 Report Share Posted May 25, 2011 Datzenwizard is spot on . when I was new to the L motor I had the first head done and it was a rinky dink place. But I had to question the machinst how he did the head. I asked and the machinist showed me how he measure the valve stem height. I told him I needed to use the same lash pad size with in hopefully .010Like having a straight edge across all the valves would be perfect. He stuck a valve in and had a dialgauge on the other side so I can see how much it pushed thru. Then when i did the rest at home it came out OK. I have a spare head now that Im looking at redoing. I know the # 3 exhaust is sunk were Im out of valve lash. So do I risk a new valve seat(as they can still come out ) or use another head that I know is better on the rocker arms lash/valve seat height and just do a basic regrind. then put a new cam in that. So I guess maybe you could have started with a better head. better machinist ect... to prevent some of this. The earlier heads could have more sunken valve seats till the later unleaded heads came along or if they were really but think maybe those are intakes have softer seats cant remeber. Unfortually you are learning the hard way, and costing you $ Then find out a Weber DGV with this cam isnt going to be neckbreaking. As sidedrafts really wake up a motor with a cam. But youll notice hopefully a different and once running youll feel good what you have done and can put other carbs on later. But thinking you have a truck a downdraft is best for the lowend up in the mountains Setting up the heads correctly is a very long process. You change one item and it effects five other things. On a street engine you can let a lot of the small stuff slide, i.e. small changes in combustion camber volume , flow, spring pressure, but the cam geometry is not one of them. As I said, before most Chevy ,Ford machinist don't understand the L-series heads and the geometry. Also one thing that I haven't bought up is the contact between the rocker arm tip and the top of the valve stem. Ideally at half valve lift , you want the center line of the stem to be inline with the center of the rocker tip for maximum mechanical efficiency. The rocker tip as it is going thru it motion is actually sliding across the lash pad. The lash pad thickness also affects this positioning, but you can't see this because of the sides on the lash pads. On a street motor, I wouldn'tworry as much about this, just get the cam wipe pattern to be centered or for a little more lift move the pattern toward the rocker, but stay back from the edge about a 1/16" . One thing about the valve seat in the head, you can increase the interference fit to about double if you heat the head to 390-400 degrees and freeze the seat before installation. Of course need over sized seats. Quote Link to comment
Sealik Posted May 30, 2011 Author Report Share Posted May 30, 2011 Better machinist..?..better head...? :lol: Other than what Merlin has...I believe I have the last L head in town. I don't mind paying a few extra bucks to get a 37 year old head up to snuff..... having a machinist that actually knows something about Datsun geometry would be a plus though. There are only a couple of machine shops to choose from....this one was recommended. Not to many options here......relative to you guys south of the border....or at the coast. I'm only out about 150 bucks on the head....those parts can be sold or used for another project. If the head was rebuilt to specs and Nissan Motorsports/Nissanparts.cc could of supplied the appropiate parts....I would not be in this position. There is some good that came out of this though.....did learn quite a bit....as others no doubt... :thumbup: Sooooo....it's not a total loss. :D The head was dropped off last Wednesday....the owner wasn't in at the time. I explained the issues at hand and the guys seemed to grasp the situation. No call yet.....humbled by his lack of Datsun geometry I guess. I weighed all of my rockers....there is about 5 grams difference between some of them....mismatched set. Not sure of the acceptable variances in weight....sooooo...I have a new set of rockers coming. Here's a link for some others.....20 bucks a pop....delivered....good price Not sure if they are factory seconds though....read the fine print....email seller to confirm. Not for me though.....no international shipping....as usual http://cgi.ebay.ca/OEM-NISSAN-DATSUN-L-Series-Rocker-ARMS-NOS-Set-8-/330509225328?_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D2%26po%3DLVI%26ps%3D63 Quote Link to comment
banzai510(hainz) Posted May 31, 2011 Report Share Posted May 31, 2011 The head was dropped off last Wednesday....the owner wasn't in at the time. I explained the issues at hand and the guys seemed to grasp the situation. I learned never go thru another guy!!!!!!!!Tell him your self. 5 grams diff on rocker weight? what the new set going to be. I bet the same. I wouldnt worry about it. long as they are new rockers with new cam.Its not a 7k rpm motor your building. Quote Link to comment
datsunwizard Posted May 31, 2011 Report Share Posted May 31, 2011 5 grams diff on rocker weight? what the new set going to be. I bet the same. I wouldnt worry about it. long as they are new rockers with new cam.Its not a 7k rpm motor your building. What Hainz said, the weight is not critacal on a street motor and in fact matching the rockers for lift is nice, but isn't nessasary for a street motor. What is critacal is the geometery, focus on that. You want the motor to last! Thats the important thing on the street. What cam are you going to use? How is it oiled? Quote Link to comment
Sealik Posted May 31, 2011 Author Report Share Posted May 31, 2011 I was curious about the weight....so I weighed them, just for the hell of it... :D The issue was that they came from 2 different engines/mismatched.....and new rockers are going to be MIA in a couple of years, or less. New cam.....'new' rockers...which should result in a thinner pad. Pretty simple directions......"wrong exhaust valves and all the retainers have to be level"....besides....the owner doesn't do the work....they do. When I get the head back...I'll do a wipe pattern with the new and used rockers, and note the differences. The new rockers might not be even used on this head....have to wait and see. Cam is a Shadbolt....advertised with .491 lift....calculated at .470ish Quote Link to comment
Sealik Posted June 2, 2011 Author Report Share Posted June 2, 2011 My machinist does not understand why I would use various sizes of lash pads to obtain a correct wipe pattern. Figures I can adjust it by the changing the valve lash clearance.... :blink: Excellent....I know where this is going..... :huh: I tried to explain....but...does not grasp it. Quote Link to comment
Sealik Posted June 7, 2011 Author Report Share Posted June 7, 2011 Got my NOS rockers. Still waiting for the head.... Quote Link to comment
datsunwizard Posted June 7, 2011 Report Share Posted June 7, 2011 Got my NOS rockers. Still waiting for the head.... Some more input, if you don't mind. Debur the ends of the valve springs, so they don't chew up the alumiunm retainers. Make them nice and smooth. Whats the latest on the head? Is "The Machinist" going to make it right? Quote Link to comment
banzai510(hainz) Posted June 7, 2011 Report Share Posted June 7, 2011 print this for him! http://www.spannerfodder.com/the_works_escorts-generic-image.php?imageName=images/the_works_escorts/pinto/pinto-rocker-ratios.gif Quote Link to comment
Sealik Posted June 7, 2011 Author Report Share Posted June 7, 2011 Some more input, if you don't mind. Debur the ends of the valve springs, so they don't chew up the alumiunm retainers. Make them nice and smooth. Whats the latest on the head? Is "The Machinist" going to make it right? Please....input is good... :) Those are the .190-.240 (blue) retainers...most likely for another project....too tall. The Isky retainers I cut down might be used...but...not sure now if they will work with anything other than a Isky inner. If you see here...the Iskys have more of a seat (for the inner spring) than the stock L or Motorsport retainer. Motorsport 2 mill...stock L...about 2 mill....whereas the Isky has about 5 mill. From the crappy internet pictures I've been able to find on the Isky inner spring.....looks like they have less coils, spacing between the coils is more considerable. I'm thinking the stock L spring (or Motorsport) spring will have a tendency to rub on the seat???? This would happen when the spring is compressed.....2nd coil down from the top of the spring might hit the tapered edge at the bottom of the retainer??? Theories? I'll use the stock retainer if the pads are 180 and under. "Machinist" says he'll try to get the valve stems close.... But, to do so.... he'll also have to put a new valve seat in No 4 exhaust. Also stated those are stock exhaust valves he installed...as compared to the old ones. I told him that the old ones might not even be stock..being that they are longer than stock specs. Quote Link to comment
Sealik Posted June 7, 2011 Author Report Share Posted June 7, 2011 print this for him! http://www.spannerfodder.com/the_works_escorts-generic-image.php?imageName=images/the_works_escorts/pinto/pinto-rocker-ratios.gif Ya.....I emailed him last week with that info. I jotted down those directions a couple of months ago when I did my first wipe. Quote Link to comment
Sealik Posted June 10, 2011 Author Report Share Posted June 10, 2011 Got the head back....looks good. They replaced the exhaust valve seats and trimmed the exhaust stems. Did a initial wipe pattern on one intake and exhaust....180s with the old rockers, pretty much centered. Fine tune later.... Recalculated the cam....1.542-1.217 = .325 x 1.48= .481 lift. Not far off the advertised amount of .491 Was concerned about the stock L inner coil binding... Have a little more than the recommended .015 clearance between coils....good. A little less on the backside because the inner isn't holding the retainer true to the head. Outer spring is the Comp #906...not the Motorsport spring....lots of clearance. Thoughts...? :) Would like to use the inner springs I got from Motorsport...but not sure if they are the correct part... Quote Link to comment
datsunwizard Posted June 10, 2011 Report Share Posted June 10, 2011 Are those the retainers that you are going to use? If they are, you need more support on the lash pad( taller retainer). Quote Link to comment
Sealik Posted June 10, 2011 Author Report Share Posted June 10, 2011 Are those the retainers that you are going to use? If they are, you need more support on the lash pad( taller retainer). Well...the guy at Specialty Engineering suggested I could go up to a 180 with the stock retainer. ?? Looks like about 65% + of the pad is in the retainer. Could use the Iskys....but not sure about them though Or....could use the new rockers with some 170s Opinion on those inners? Quote Link to comment
Sealik Posted June 10, 2011 Author Report Share Posted June 10, 2011 Check this head out. I mentioned the amount of pad sticking out....but.... it was of no concern...Robello built the head. Mine looks like the one on the left Confusing... :D Quote Link to comment
datsunwizard Posted June 11, 2011 Report Share Posted June 11, 2011 Are you sure that rebello build that head? Look at those different sized lash pads, they sure didn't equalize the valve stem lengths. Back to the retainers, I would like to have more support on the lash pads, just like the stock way. If you could get 75% I would feel better. Are you mixing different brands of valve springs? What does the cam manufacture recommend for springs? The cam manufacture should state the pressures required with the valve seated and opened. Quote Link to comment
Sealik Posted June 11, 2011 Author Report Share Posted June 11, 2011 Are you sure that rebello build that head? Look at those different sized lash pads, they sure didn't equalize the valve stem lengths. Back to the retainers, I would like to have more support on the lash pads, just like the stock way. If you could get 75% I would feel better. Are you mixing different brands of valve springs? What does the cam manufacture recommend for springs? The cam manufacture should state the pressures required with the valve seated and opened. Yup....Robello http://community.ratsun.net/topic/26256-codys-green-69-510-4-door-gumby-power/page__st__80 Trying to figure out the springs right now... :blink: .... :D Nothing was suggested by Shadbolt for springs. Stock L inner is close to binding...outer will work I think. Have some Comp springs the "machinist" supplied.....but after further inspection..ID is a little more than stock... movement in retainer. 1.013 (Comp) and 1.001(stock) approx. Can't find any .150-.180 retainers anywhere. Also have a set of M-99996-M1046 from Motorsport....was not sure if they are correct. Also...when using inner and outer springs...the coil lean has to be opposite of each other??? I could use these Iskys for more support??? Emailed the tech guys at Isky....no reply Here is my starting lineup....lol 2 stock Ls....2 Motorsports...1 Comp. EDIT No change on lash pads between new and old rockers. Here's the Comp specs. Quote Link to comment
banzai510(hainz) Posted June 11, 2011 Report Share Posted June 11, 2011 I think the lash pad is too much sticking out esp #2 and #3 rocker that I see. Im sure it will work to get running. Dude its time you to run this your milking this cow out to long. the valve stem height are all the same(pretty close is good enough) now right.? Your new lift is 481. Then maybe just put both motorsports springs in and see if the isky reatainer you modded will work now with the lash pads you have DONE!!!!!!!!!! Prime fuel pump and carb Prime oil pumps set valve last set distributr and it will start up! Quote Link to comment
Sealik Posted June 13, 2011 Author Report Share Posted June 13, 2011 I think the lash pad is too much sticking out esp #2 and #3 rocker that I see. Im sure it will work to get running. Dude its time you to run this your milking this cow out to long. the valve stem height are all the same(pretty close is good enough) now right.? Your new lift is 481. Then maybe just put both motorsports springs in and see if the isky reatainer you modded will work now with the lash pads you have DONE!!!!!!!!!! Prime fuel pump and carb Prime oil pumps set valve last set distributr and it will start up! You do realize that is not my head in pic....?.... :) The modded Isky retainer fits perfectly for a 180+ lash pad. My concern was the longer stem at the bottom of the retainer, holding the inner spring.....possible rubbing issues. And yes.....Milk.....does a body good.... :D The roadster springs are a little excessive I think....was suggested I should use a spray bar if utilized. 99996-M1046 Coil bind at .970 280lbs/in OD 1.34" assem height 1.72" seat pressure 120lbs Pretty much double the specs of stock springs. Assembled those in my head....very stiff...could not push open by hand. My installed spring height is 1.70 with the Isky retainers. Since you have installed and ran inner and outer springs that lean (coil) the same way, with no issues....I will use the Comp (outer) spring and the roadster inner. The Comp has a slightly larger ID, less interference with inner coil. Comp seat load is 60 lb at 1.60. Not sure of the combined seat pressure....but much less than 120lb. Could push the 'loaded' valve open by hand. Noob spring pressure tester.... :lol: Quote Link to comment
banzai510(hainz) Posted June 13, 2011 Report Share Posted June 13, 2011 now you have roadster springs? Now Im more confused. spray bars are for cam with a hole in the back(unplugged) Run a KA oil pump!!!!!!!!! Quote Link to comment
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