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Mack

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Everything posted by Mack

  1. a lot of the stuff is pretty close. head bolt holes are pretty damn close, and you could probably make it work just by offset drilling the MB head holes closer together (side to side, not front to back, obviously). The only other major hurdle is the thrust bearing location. Merc has it betwen cyl 4 and 5 and L is between 3 and 4. Not insurmountable, but just to give you an idea of what you will be dealing with.
  2. Ive got the swap, I hardly even notice the shifter position.
  3. there are ways around this. S13 rears bolt right in if you modify the top mount to fit in the 280ZX strut tower. the fronts.... require a bit more modification. I've stalled in the middle of putting S13 front hubs and coilovers on my 280zx using mostly off the shelf parts and the stock 280ZX lower control arm. the only piece of the puzzle I havent figured out yet is the fact that I need a longer tie rod. Inner or outer, doesn't matter, it just needs to be longer by about 2 in on each side. But then I will be able to run 300zxtt big brakes by simply bolting them on and full S13 coilovers with the height adjustability independent of pre load.
  4. I rated the cam before the head work and throttle body, because you need the cam to take advantage of both of those. and swapping out a cam can be done without pulling the head. Porting the intake really won't do anything, at least on an EFI intake. You can smooth it out, but to actually port it would be a huge pain in the ass and you may as well build a custom one at that point. That being said, I did take the injector screw bumps out of the ends of mine as well as smooth out any bumps and ridges I could get to. if you want more compression, you'll need a different head or to severely modify yours. at that point, all bets are off and you may as well do some porting, polishing and cam swapping "while you're in there". You will end up with a few more than an additional 20 to 30 at that point.
  5. Some ways for more HP... easiest to hardes. A cold air intake/aftermarket air filter/mod your stock air box. 2.5 mandrel bent exhaust. with the proper muffler, it SOUNDS awesome as well. a header. although it wont do much other than sounding cool without a lot of other work. A cam. easy, bolt in power if you know how to work on these engines valve bowl work. Just blend the valve bowls into the upper portion of the seats if you ever have it off for a headgasket. more compression. flat tops and the .080" P79/p90 head mod. Or the maxima N47 head. Megasquirt. one of the BEST bang for the buck mods out there. hands down. definitely NOT for the inexperienced mechanic or tuner. I did all of these, except for the cam and the header. I also added a 60mm 240sx TB and got a bit crazier with my cylinder head porting on a maxima N47 head. My car (1980 2+2) went from a high 17 / low 18 sec stock 1/4 mile to a VERY low 15. That is on a puny stock cam. Next mods are a regrind, which I have sitting on the shelf, and a custom ITB manifold, as the stock intake manifold is very small and restrictive.
  6. I wonder why the torque was so low in comparison to the HP?
  7. thanks BLOZ UP! I was kind of worried for a second there, but then I figured teh z stores disclaimer is probably a blanket statement left over from the L series, which are a lot more finnickey about cams from my experience. I am probably going to get this regrind. 131H because it will allow me to retain my stock springs and it won't be too wild, as this is still in a truck. no need to build a high rpm monster, haha! I think a retune would make it run optimal, but without it, being a MAF system, it will still put out more HP because the MAF is measuring air coming into the engine and giving it the required fuel. My xterra is a 2001 and I am going to lightly port/port match the heads as well. I got my ideas from this article. pathfinder build They supposedly picked up 4mpg on the highway, even while towing!!!!
  8. Hello, I am in the middle of a headgasket on an xterra (suprise!) and I figured I may as well throw a set of cams in it too "as long as I am in there". I have found conlicting ino on the net about what needs to be done. Can I use regrinds? the MSA site sells regrinds but only offers "Warranty on camshaft requires use of new rocker arms, proper springs, proper lifters " what the shit does that mean? why would I need new rocker arms when it doesnt even touch the lobe directly? I called them and they of course were no help. They just recommended replacing the entire valvetrain because "previous wear on old components could cause premature wear on the cams" Right. JWT wants $560 for a set of billet cams. that's a bit steep. What are you guys running on yours?
  9. I am very interested in this build. I still have the block I took a crank out of and sold many moons ago, as well as a COMPLETE LD28 that I am holding on to for now.
  10. also, keep in mind, calculating the difference in diameter would give a better indication than the total area, since the middle of the valve is solid and air only flows around the perimeter of the valve face.
  11. I am looking to purchase a 280ZX gnose for my kaminari widebody car. If anyone has one or knows where to get one (short of importing from JDM land...) please, contact me or post it in here. I'd even take a shitty zforceproductions one if someone wants to get rid of it. I can pay or trade parts for it. thanks!
  12. You might want to give Guy Henson at Damn Good Motors in Minneapolis a call. He is a real personable buy and does some of the best custom cam work I have ever witnessed. He even designs his own camshafts, down to the profiles and ramps for existing engines and has worked on some rather odd stuff. He is VERY good at one offs and customization.
  13. yeah, you really need a maxima N47 (or shaved P90/79) to run those numbers. I ran a stock MN47 on an f54 flat top with a felpro gasket for years. (daily drove in phoenix heat too!) Hell, it would probably still fire up if I put the intake back on! the calculated cr on that is about ~11.5:1. it ran on pump premium with a total adavance somewhere in the high 20s. with a stock cam. keep in mind that the more quench the less advance you NEED, as the flame front doesnt need to travel as far. Having MS&Se helps a lot as well. EDIT: to throw in some experience that pertains to the original content of this post, before I installed the head I gave it a very mild port job that was basically limited to cleaning the casting lines and blending the step right above the valve seat into the bowl. I also port matched the gasket and the intake as best I could. All was done with just burrs and a dremel. no polishing. When I pulled the intake off, the ports looked fairly clean. FWIW, but anecdotal at best.
  14. See if you can get some before and after flow numbers with the valves. I'd be interested to see if they make that big of a difference!
  15. the benefits of it would be that if you had fine enough electronic control out of it, theoretically you could throttle the engine with it and run a 300 + degree "full race" cam and have all the power in between that your little heart desires. You could also set it up completely mechanically, but the control would not be optimal. Complexity? not much really. it would add a few moving parts to a standard head. nothing nearly as complex as the vq37hr system, or even a honda vtec for that matter as it uses a hydraulic lifter esque part. I know all of you are thinking "oh great, now we won't be able to wick the RPMs up" But there have been recent engines built with hydraulic lash adjusters that are very capable of 8500RPM in STOCK trim (check out the vw 07k!) The Jury is still out on cost. I'll know more after I have a chance to speak with the patent attorney. That will hopefully be soon, but as I understand it he is dealing with family issues in rexas right now. And TimZ, I am glad someone appreciates my avatar!
  16. I know this has probably been covered a thousand times before, but I have an idea that would be easily retrofittable and could even be made 100% mechanical with no need for electronics what so ever. This system will essentially work on ANY non shaft mounted rocker arms (yes, SBC, SBF and mopar) Cost shouldn't be too bad, as there isnt much complexity or need for a whole slew of new parts. Some minor modification to the cylinder head and valve cover, but other than that it should be a bolt in affair. I have spoken to an engineering firm about this and they seem to think it is feasible enough to at least warrant building a prototype. I am also waiting to speak with their in house patent attorney about filing a provisional patent, at which time full details will be released. It would essentially do what the intake side of the vq37hr VVEL system does, except a lot less complicated, and easily made to work on the exhaust side as well. So, any interest?
  17. The MN47 head is fantastic. With some very mild porting work (port matching gaskets and cleaning up the valve bowls) it will flow jsut as good as a 2.8 head, and with the smaller valves, you will get increased port velocity. also, smaller valves means less valve shrouding. Plus, with the small combustion chamber and its high quench design, it will be more efficient and require less timing advance for the same amount of power. The valve size isn't really that big of a factor because the intake manifold runners are so damn small on these engines. I would look into the LD28 intake manifold, if you have the means to convert it. THe runners are substantially larger diameter than even an L28 manifold. Someone was messing around with a dual throttle body set up using SU manifolds, but I do not know if this ever came to fruition. Might be something to look into .
  18. On the cams note, something I have considered while dreaming up stuff in my head that I have no money for.... How about a modular camshaft like Ford used on the 4.6s? cut the lobes and bearings out of whatever material you want and use an EDM to slice them like loaves of bread. Maybe an indexing keyway cut into the cam and lobes to make sure everything lines up right, bingo.
  19. If high compression with maximum ping resistance is what you are after, look into a maxima N47 It is a completely different animal than the Z N47. they were available in the 1981 to 1984 datsun 810/maximas that came with an L24E engine. MADKAW you have a PM as I didn't want to thread jack.
  20. What are you having done with your head? I would look into a P79, P90 (both at 53.6 CC combustion chamber) or MN47 (a maxima N47 which has about a 40cc combustion chamber) as they have a much better closed combustion chamber that resembles SBC aftermarket heads and many people feel work better with flat top set ups. I run an MN47 on my bone stock L28 F54 flat top set up which produces about 11.5:1 compression! yeah, its high, but it also produces a LOT of torque because of the compression ratio but also because the MN47 has 42mm intake valves as opposed to 45mm on the L28 stuff. LOTS of velocity. I have not installed an aftermarket cam on this yet, and I do have to pull a bit of timing, but I am running megasquirt controlling fuel and spark, so my situation is a bit different than running carbs and a regular distributor. I feel an aftermarket cam with more duration could be the hot ticket with this set-up.
  21. The turbo charged cars also came with a significantly more advanced computer control system from the factory than the N/A cars did. The ECCS system was light years ahead of the L-jetronic. I don't think a non hydraulic cam will work in a hydraulic head. You would be better off just grabbing the P79 and running that until you can find all to proper components for the P90a, or you will have to do a hydraulic to mechanical conversion on the head using time-serts threaded inserts. Get the P79 head, blend the valve bowls, bolt a turbo manifold on it and forgettaboutit.
  22. Yeah, oil brought one of the engines up some, but the other was still low. I made a leak down tester and I'm certain the issue is valves now. Burnt valves, to be exact. Cylinder 1 is about at 95% sealed and the next highest is around 45%. I spun the engine with a ratchet on the crank pulley with the tester in the plug hole and air never stopped coming out of the exhaust on most cylinders, some the intake too. Time for a valve job. Can you post a link to the manual?
  23. I am putting a Z32 back on the road this summer. The engine that is in it has a rod knock. that one is shot. I have an engine that I pullled out of car that last ran 5 years ago that I unfortunately put into a wall during a track day. I also have another engine that was pulled from a t-boned red light runner about 6 years ago. Obviously, neither one of these engines have run in quite a while. I tested the walled car, all spark plugs out, one cylinder at a time with a battery and the starter still hoooked up to the trans. I got anywhere from 45psi to about 90psi except for one cylinder at about 150psi. I checked and all timing marks line up, so I know it's not that. I checked the T-boned motor the same way as the walled car, and every cylinder is about 45 to 60 across the board. I KNOW for a fact the walled car ran and drove, and boosted quite well. The other one, I bought on the guys word. So, is it possible that both these motors are Fizz-ucked? or am I dealing with hydraulic lifter bleed down? (as both have been sitting for at least 5 years) does something need to be done with the VTC? the tests were done with just the positive and negative hooked up to the starter with a jumper button thing. No fuel, no spark no ECU.
  24. I just purchased another 280ZX. I rescued a 1983 280ZXT 5spd 2 seater with 97K, that had been sitting in a barn since 2004. It was posted on craigslist for a song and a dance, so I called the guy, he told me it was sold and someone was coming to pick it up the next day and that he would call me if it fell through. In the grand tradition of craigslist deals, the guy flaked and never showed or called. His loss, my gain. I am working on getting her running right. I am pretty sure she needs a fuel pump and an oil pressure sending unit as it reads 0 psi, but the light is off and the lifters are SILENT ( I can hear the injectors clicking over the engine running), which would not happen if it indeed had ZERO oil pressure. The rust situation is minimal. one or 2 soft spots in the floor and surface rust on the wheel arches as well as a couple spots on the hood. Solid rockets and frame rails though! I'll probably make it daily drivable and pass it on to a deserving home, as I have too many projects as is right now and I already have a 280ZX that is "my baby".
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