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thorfin

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About thorfin

  • Birthday 07/25/1952

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    Oklahoma

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  1. by jimbo, steveosupremeo is right, and upon an inspection of my two shim tracings, there are three holes in each shim--two for the cam tower bolts and one for the head bolt--three total----BUT m4xwellmurd3r is also right----the total height of headafter milling and shimming is the same still about the same and thus the head bolt is not too short--in fact, most of the bolts will have a bit more bite with the slightly thinned milled head.
  2. Some additional comment on the shims--you do not need to have an expensive aftermarket chain tensioner--unless you just want it!--As far as cam tower shims are concerned, there is a relatively easy solution (since Goodson apparently doesn't supply them anymore). First of all, you don't need to worry about the headbolts being too short---- the shims go under the cam tower bolts, NOT the headbolts!--in effect they make the cam towers a little taller, and this does not affect the head or head bolt connection. Now I will tell you a fact--the BEST cam tower shim will be one solid shim that is .080 thick or thereabouts--rather than a 5 to 6 stack of thin shims--and the thickness does not have to be perfect match to the amount milled off--let me explain, the factory manual allows you to mill the head up to .030 when doing a head job-----with such light milling, the chain will just be a little more slack, and there is a chain tensioner near the crank shaft to keep this slack under control--but it has limits, and .030 is the limit--so when you mill off .080 you have to get back in range of the chain tensioner--so a range of .075 to .081 will make no or little difference--close enough! Now another thing to keep in mind is these L6 heads are notorious for head gasket leaks and warped heads--too common--a weakness--so you need to make sure your redone head is flat on the bottom AND flat on the top--and both are parallel to each other---so it is a very good idea to have the machine shop mill the top flat-- FIRST-- by taking a skim cut--and if the head is not warped, this skim should be about .007 or so on the top--this way your cam towers base areas are going to be flat and parallel to each other--and THEN the head is flipped over to mill off the combustion chamber side--milling off the bottom say .078--then you TOTAL head thickness has shrunk in height by .085 inches--so a perfect cam tower shim is .085 inches thick to compensate--but as stated earlier .075 or .080 works fine too. Now for the shims--they must be THEN be custom made--there will be two types on the L6 head and a total of five needed --one for each cam tower--it seems like there is one of one type and four of another--total of five--you can tell by looking at your cam towers after they are unbolted from the head--BE SURE AND NUMBER MARK TOWERS #1 thru #5 BEFORE UNBOLTING THE CAM TOWERS!! --you can use the cam tower bottoms as a pattern for the shim--if you are REALLY going to do this, and want it, I have the two cam tower patterns traced on a piece of paper that I could send you--I also send one of the Goodson shims--it was leftover--do not have second type of Goodson shim for some reason--just the two pattern and one actual .015 thick shim--take the towers (or my pattern traces) to your GOOD machine shop and have them make the shims--it would work best if they got some genuine shim stock or good sheet metal that was already .075 to .080 thick--but do not get the final shims made until your head is milled and competely done--you may need it to be .090 or so because the head was warped! the exact outer shape of these shims is not critical--what counts is they are flat with no burrs or rolled edge--so that each tower is raised consistently--anyway-if you really need and want the pattern traces and sample shim, send me your address and I will mail them to you..--thorfin
  3. I did this p90 modification in 2004. It is not easy to do right-- You will want to use or have flat top pistons and you will have a 10:1 compression, and will need to use premium gasoline thereafter. so my advice is make sure you really want to do it--takes time and study. Recommend to get the datsun hotrodding book and study up on method of adjusting the the lifter shims--these are different than the cam shims. You need to be very good, or have a shop that is expert with the z head. Here is a link to the shims, made by Goodson.com--you need the DHS-60 model shims---and do NOT use more than five(5) sets of .015 shims--more than 5 equals a problem! I don't know if Goodson makes them still------you will have to call them. 1-800-533-8010 about $80 for five sets. I have their catalog but don't see DHS-60 on their website now--Call! These are very precision with no burrs--you need to have consistent very flat shims to insure no problem with your cam alignment. http://www.goodson.com/technical_support/instructions/DHS-40.pdf OK!-- also the valves you want are made by "SI Valves" and they are the very SAME manufacturer that Datsun Competition catalog lists. I used the stainless steel swirl polished version and they were half price DIRECT from SI, compared to distributors like you listed--mine were $9 each in 2004. Here is a link to the valves I used-- http://www.sivalves.com/ocforeign_valvessp_nis.html To get a good cam wipe pattern on my performance cam I had to actually trim a few of the valves a few thousands in length to custom fit each one --again you need a very good auto machine shop to help do this correctly--it is not done by hand--need proper valve machine fixture to grind 100% flat and parallel. Have fun! it does work as described in article. ---Thorfin
  4. The army is will pay you a $50,000 sign-on bonus.
  5. Hey --my bad !--my comment and advice above was for the SIDE windows--yes you have to cut the hatch seal--be real careful ---easy to drop glass hatch and break once seal is cut all the way around.
  6. Use a long bladed thin flexible serrated kitchen knife (don't tell the wife/girlfriend) and slide it in the accessible area of the glass (from the inside as I recall) and "saw" that seal over about one side of the glass(one side)--then gradually strart to put some prying force on the glass in the area of the cut seal area--not so much that you risk breaking the glass---- with some pressure and time the remaining seal will start streching and releasing and you can then more easily finish sawing/cutting the seal--this takes about 15 minutes a side to do---the seal is some kind of heavy super sticky tar that can never be reused--after the glass comes off you can finish snapping this stuck-on remaining tar off much like removing sticky/hardened gum--then when you get 90% of it off use some disc brake cleaner or carb cleaner on a rag to finish dissolving the remaing stuck on black glue. For reinstallation, I recommend using a uniform and fairly wide bead of black silcone rubber(RTV), applied 360 degrees around the glass seal area, and then press /position glass until it sets up--have fun!
  7. Agree you should use an initial light coat of adhesion promoter if taken down to bare plastic. The paint system I use then calls for one coat of sealer, then followed by bc, cc--two coats each of bc&cc with 30 minutes of flash between coats.
  8. Really liked your video--I smiled the whole time--enjoy your success!!------LOL with you struggling to find the right tap at the hardware store--I've been to that same store and its great because you save a lot of time cause they don't have what you need, and then you go home!
  9. A good possibility is your fuel pressure regulator has failed. This is very common for age of car. When it does, the pressure at the injectors goes to about 75psi instead of about 32 psi. You have to install a pressure gage in the line to tell for sure, which is a pain in the *** ! But an indirect couple of clues will be you will often hear an extra irritating buzzing noise coming from the rear of car at idle--this is the fuel pump being overloaded and the pressure relief on the pump venting gas back into the tank--also the inside of the tail pipe will be sooty black-black due to running way too much fuel-- extra rich mixture. I've had three zx's do this so I think it is an inevitable failure. The fuel pressure regulator sits on top of the fuel rail and it costs about $80. although right on top in plain view, it can be a little booger to change because the hoses are all old and hard-- if so use use new hose--high pressure injector hose--very important--it costs about $5 a foot for the correct hose--- 5/16" as I recall works good as a replacement--anyway the regulator is something to suspect--I wouln't have brought it up but it took me quite a while to figure this out and a lot of extra gasoline.
  10. The short answer is --NO--NEVER. Get a new OEM Nissan set(can get from MSA)--that is the best thing to do. These rockers have a special hardened wear area that will destroy your new cam unless new. Or, you can have your old ones resurfaced by Delta Cams--they have done this for lots of z cars--below is a link to them--call for a current quote. It seems like they charge about $4 each, times 16, plus shipping. http://www.deltacam.com/index.php
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