letitsnow Posted October 19, 2011 Author Share Posted October 19, 2011 (edited) I'm hoping that it's just a bit of crap under one of the towers that I didn't clean well enough, the old cam spun pretty freely, maybe not '2 finger' but better than this. I'm nearly positive I didn't mix up the towers. When I put it together last night I got 2 finger and 2 hand mixed up and thought I was alright until I did some research. Should hopefully be able to tear it back down tomorrow, if I. A major revelation I had turning it over while I was setting the lash, I could feel the compression stroke, I never could with the old valvetrain. I just attributed it to being a small low compression engine, being used to large-ish, high compression v8's. Edited October 19, 2011 by letitsnow Quote Link to comment Share on other sites More sharing options...
CamH Posted October 19, 2011 Share Posted October 19, 2011 Keep in mind your old setup was hydraulic so it may not have been 'pumped up' completely when you were trying to spin it over by hand before. There wasn't any oil pressure. Also, it was my understanding that cam towers will wear to the cam a little, so a cam may not spin as freely as you'd want it to on a fresh install. Everything will wear in and it should be fine. Quote Link to comment Share on other sites More sharing options...
calvin280zxt Posted October 19, 2011 Share Posted October 19, 2011 im interested to see your results of the n/a cam, as i have an 82zxt and an 82 n/a parts car decaying in my dads back yard.. i like cheap/free horsepower. also curious because mine falls on its face at 4500 at 10 psi but not 8 psi, thought i have a regular p90 so thats not an issue Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 19, 2011 Author Share Posted October 19, 2011 http://www.atlanticz.ca/zclub/techtips/cam/index.htm That has the specs for all the factory L series cams, the '82 N/A is kind of in between the turbo and the s30 L28 N/A cam. My comparison won't be apples to apples as I was having mechanical issues that the cam swap solved. The p90a also has the smallest of all L series cams. I can say that it is leaner up top, meaning more air is being ingested, and the car does pull harder above 4000rpms, smoothly up to 6k. Now, off to tear it apart again. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 20, 2011 Author Share Posted October 20, 2011 (edited) Well, I think the head might be warped. at least the top of the head. I can torque all the tower bolts(10ftlb) and head bolts(25ftlb, to test alignment) except the center and it will spin freely, tighten the center and it binds right up. I noticed what feels like a ridge in the shape of the tower under the center, like the tower indented the head slightly. Do I have any options other than: 1) put it together and forget about it 2) pull the head and have it machined I don't really like either. Edited October 20, 2011 by letitsnow Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 20, 2011 Share Posted October 20, 2011 "Also, it was my understanding that cam towers will wear to the cam a little, so a cam may not spin as freely as you'd want it to on a fresh install." This is ABSOLUTELY INCORRECT! The cam should NEVER run on the aluminum bearings except at startup under valve spring pressure. As soon as lubrication is supplied it will run on a film of oil. There is NO 'wearing in' of the cam towers. Anybody stating there is is missing the line-boring concept, or has improperly installed them and used that as an excuse to justify not going back and making it right. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 20, 2011 Author Share Posted October 20, 2011 (edited) Would it be a terrible idea to buy some .001" shim stock and make my own shims to get it to spin freely? Edited October 20, 2011 by letitsnow Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 20, 2011 Share Posted October 20, 2011 If you can identify which one is low or warped I could see that working...but.... Quote Link to comment Share on other sites More sharing options...
calvin280zxt Posted October 20, 2011 Share Posted October 20, 2011 http://www.atlanticz.ca/zclub/techtips/cam/index.htm That has the specs for all the factory L series cams, the '82 N/A is kind of in between the turbo and the s30 L28 N/A cam. My comparison won't be apples to apples as I was having mechanical issues that the cam swap solved. The p90a also has the smallest of all L series cams. I can say that it is leaner up top, meaning more air is being ingested, and the car does pull harder above 4000rpms, smoothly up to 6k. Now, off to tear it apart again. yea, may hold out for an "A" but looks like an "F" would be a big improvement over my "B" cam, to bad my parts car wasnt 2 months older.. woulda had an "A" Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 20, 2011 Author Share Posted October 20, 2011 The B and F are identical, except the F has a 4 degree advance, not worth taking the valve cover off. If your turbo cam is a J, then maybe, but I'd only bother if you have some time to kill. I think I'm going to pull the warped head and put on my extra P90(solid) head. The cam spins freely in that, so I don't think it's warped. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 21, 2011 Share Posted October 21, 2011 If you have an ADJUSTABLE TIMING GEAR you can make a "B" an "F" and vice-versa! I have a Tomei, and love it! Nothing like dialing in the EXACT cam setting that nets you best power under curve. Usually it's not 'straight up' but 2-3 degrees one way or the other. The effect on Torque can be spectacular... Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 21, 2011 Author Share Posted October 21, 2011 Tony, I was wondering what your thoughts on reusing MLS head gaskets were. My kameari gasket has been used twice now that I know of. Last time some of the rubberized coating peeled off, so I scrubbed it to bare metal and liberally applied copper coat. Working under the valvecover, I noticed what looked like a small amount water pooled in the low spots of the head, the oil was not milkshakey and the water was clear, not antifreeze. Think it was condensation? Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 22, 2011 Share Posted October 22, 2011 Yep! MLS do not compress. They are resuable. Short drives like when testing an engine leads to condensation. If you don't get it up to temperature (oil to 200+) then you will have water in there. If you have a PCV under a slight vacuum in the gearcase, you will 'boil' at a marginally earlier temperature as well. Usually the oil is hottest rolling in from the head, or directly off the bearings---that is where water should be flashing off to steam to be evacuated. If you don't have some place for it to go (PCV, or enough blow-by flow from bad rings to push it out your road-draft tube...) it will stay in there and just build to the point that it turns into sludge. In Michigan during the winters, people that lived and worked in-town and drove less than 5-10 minutes to work would literally get chocolate mousse in their crankcase from the condensation formed in less than 1000 miles of driving (could be a month or less!!!) That's about the only positive to a higher temperature thermostat, and that's why they go in mine during the winter for the 'short drive' cars. Anything I drive for an hour at a burst keeps the 160 thermostat. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted October 23, 2011 Author Share Posted October 23, 2011 I think it's fixed, I haven't turned the boost up yet, but it's faster than it's EVER been, at any boost. Today, with the 'A' cam and my extra p90, the car ran a 13.4 at 101 with 8psi falling to 7psi around 5100. Quote Link to comment Share on other sites More sharing options...
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