Tennesseejed

Thanks for the feeback Pyro. Assuming the contour of the rocker arm is consistent, and I believe it is, it would seem that setting the wipe pattern to one side or the other on the rocker arm would only effect lateral forces on the valve stem. I realize this is pretty fully dicussed in other threads. My only concern with this head would be, given the shaving and shimming an whatnot, in order to move the wipe pattern to the valve side, I will probably need some very tall lash pads. Pic 3 above is the stock lash pad - .120" (thank you) - plus .135". So I'm at .255" already. I think I'd have to go well over .300" to move the wipe pattern to the valve side. I am having a friend machine custom lash pads. So avaibility is not the issue; the issue is having the rocker arm tip rest well above the top of the retainer cup.

Hi all, I'm currently rebuilding my first 280z head (N42) and interested on opinions as far as setting the wipe pattern. Pic 1: Pic 2: Pic 3: I gather from my many hours of reading here at HybridZ that it is accepted, if not prefered, to have wipe pattern closer to the pivot side. The cam is a Schneider Stage III and the rocker arms are reconditioned. As part of rebulding my head, I shaved .050" and had .055" shims made. Not really sure why I added an extra .005" to the shim thickness other than I am reusing my timing chain and I'm sure it has stretched some. I used SI valves which are advertised as 116.3mm (intake) and 117.3 (exhaust). Stock N42 valves are 115.2 (intake) and 116.0 (exhaust)(source: How to Modify) I figured that if I was going to shave and shim .050", and the SI valves are approximately .040" longer than stock valves, then if I needed to adjust my wipe pattern at all, a lash pad in the neighborhood of .010" - .030" would suffice. Wrong. In the picture above, I am using the stock lash pad with additional shims of .095", .120" and .135" respectively. I measured my stock lash pads at .160", but this is probably incorrect because I measured from the top to the bottom, not from the top to the bottom center with a mic. I.e, where the valve tip rests is recessed. I suspect I overlooked the fact that my Schnieder cam has a smaller lobe base in order to make the lobe lift greater. In fact, while I had my stock cam (now trashed), I measured the difference in lobe center - but have apparently lost my notes. I am asking for opinions and advice on the these four topics: 1. Of the wipe patterns in the pictures, are any acceptable? 2. Is the Nissan lash pad measured from top to bottom or top to bottom center? 3. Assuming, for the sake of argument, that my stock lash pads are .160", adding a .135" shim (Pic 3) means I need a .295" lash pad. I'm using new Schneider retainers, but the rocker arm end will certainly be elevated above the top of the retainer cup. 4. Should I go at this a different way? I.e, should I ditch the .055" cam tower shim, use a .015" set of tower shims I have and buy a Kameari adjustable cam sprocket? Perhaps there are other ideas/solutions? This engine is NA and a daily Summer driver. I am concurrently installing Megasquirt, but I'm 40 years old and my days of playing stoplight rice rocket jock are behind me. Sure, the engine will see 6500 revs when I can, but I'm leaning more towards a solid and dependable engine then trying to lower 1/4 mile times. NNTTIAWWT.

I think that's a different seller. This guy is selling new injectors w/o seals.

This guy is selling complete sets on the 'Bay for $145. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=160391474634&viewitem=&sspagename=ADME%3AL%3AOU%3AUS%3A1123 That's an amazing price considering MSA sells a single injector for $175. I have no affiliation with the seller, but did just buy a set. Disregard the generic picture in the ad. The injectors are the all black (SMP-FJ23). Even Rock Auto sells them at $100+/per. I purchased mine as part of a N/A rebuild. If you have a future need for turbo injectors, now might be a good time to consider sourcing them.

Well, I ended up going the same route as you Xnke. I gave up trying to find a vendor that stocks L6 valves from SI Valves and even NISMO dealers say it is a special order part so no joy there. SI Valves sells a 46mm intake as p/n 8000SG. Oddly, it doesn't show up on their webpage so I would not have know about it without Xnke's suggestion. Thanks. There is one other option if you want to go with SI Valves until they get another shipment of the stock 44mm intake swirl polish valves in December. SI Valve sells a 44mm blank as p/n 6108 which would need to be cut and grooved. Seemed less expensive to turn down the 46mm valves than work with the 44mm blanks. FWIW, the direct price for SI Valves is up to $11.00, but still a very good deal.

Thanks for the response Xnke. I think Coutesyparts.com includes the NISMO catalog, but I could be wrong. Do you have a part number for the 46 mm valves? I don't mind cutting down some valves to fit, though I would want to buy the exhaust valves from the same manufacturer so the stem length is the same. I also didn't see 46mm L6 vavles on the SI Valves webpage. Are you sure those 46mm valves came from SI?

Does anyone know of a vendor that actually stocks SI valves? I am trying to source one set each of the 8102E and 8001SG SI stainless valves (N42 valves). The folks at SI Valves told me they are out of the 8001SG (44mm/In.) until December. I called RPMRons and RPMMachine and they each drop ship directly from SI Valves and apparently do not carry stock. I'd prefer to not wait until December to get my top N42 top end finished. I have googled for hours and found no other dealers. I know of the Ferrea valves which are more expensive. Courtesy is $20 each. Isn't there a guy in Oregon who was selling good-quality stainless valves at a fair price? Or does anyone here on HybridZ has a new set for sale? Suggestions and advice welcomed.

To troubleshoot OE FI you have to use the EFI Bible http://forums.hybridz.org/showthread.php?t=135748 Crow, if you are not getting an injector pulse you first need to check if you are getting 12V on ECU Pin 1 with the ignition on. Go from there through the troubleshooting tests in the EFI Bible. If you are not getting 12V on ECU Pin 1 then your coil is not getting voltage from the ignition control unit (ICU). The testing procedure for the ICU is found in the FSM. I pulled an alarm system, a RF booster and a stereo installation that epitomized the definition of sub-saharan engineering out of my Z when I bought it. I've been down the road your on. Use the manuals available and keep working on it. Philbert, same for you. You mention using the FSM and a multimeter so you are certainly on the right track. Looking at the EFI schematic, both injector 5 and 6 share the same circuit. I.e., If injector 6 is getting power, then injector 5 should as well. Do the test for injector 5 on page 65. If you are not getting 12V on ECU pin 30 with the ignition on, then you have a short in your circuit. Then its just a matter of testing continuity until you find the break. Good luck.

Probably deserves it's own thread, but I have a lot of interest in the N42 shave concept after reading Babalouie's mystery engine thread http://forums.hybridz.org/showthread.php?t=141159&highlight=mystery+engine Have not been able to determine the approximate shave to make the N42 a "closed chamber" head, but I don't think finding a usable length 8mm stem valve is the hard part.

There may be more than one way to wire a 6A as stand alone (than in the OP), but you can remove the original ICU completely. Where to put the 6A can be a little challenging too. Plus it makes a little noise - kind of a soft buzzing. As far as performance gains from changing to the Blaster Coil (only), I wouldn't expect any. The reasons I would change to a complete MSD ignition system would be (1) reliability over stock system (2) efficiency/mileage, (3) smoother/easier starts and (4) stable performance at high rpms.

Josh817, thanks for posting those pics. Pretty work. Not to hijack, but do you know how much your finished rods weigh? I have searched wide but not been able to find the stock weights for 240 and 280 rods. I have been looking at the Toyota 3sgte rods as a workable replacement for a 280 build. The BE width is same and 138mm length. The only issue I see is the BE diameter is 51mm instead of 53mm. I think this can be solved by turning the main jounals down 1mm or boring the BE 1mm. Eagle says the Toyota rods are 520 grams. I think this is a lot less than stock Z rods, but I don't know how much. Jed

I installed the MSA preimum exhaust system, as well as the 6-1 header, earlier this spring on my '75 280.. The exhaust system is bolt/slip on and, imo, is a pretty well made piece. I don't know to what extent, if any, installing the header also changes install issues and overall sound compared to the exhaust alone, so take this with a grain of salt. As far as the sound, I think the "turbo" muffler leaves a lot to be desired. I get a loud/unpleasant resonance between 2000-2400 rpms above which it quiets appreciably and sounds very nice. Even lugging along at 1,500, the muffler sounds good. But with any sort of throttle between 2,000 - 2,500 its pretty awful. This could be related to having the header, which, in cojuction with the larger (2.5") exhaust did knock down some low end torque. One other issue I'm having is some rattle from the exhaust pipe hitting the underside of the differential mustache bar. This only seem to happen on take-off. It also hasn't been bad enough for me to put on the overalls and try to adjust the fit. Might get to that this weekend. Overall though, for the money, I think the MSA exhaust system a pretty good buy. I am considering buying a different muffler though. Since you are concerned about even sound, you may want to get a few more opinions before you buy. I wouldn't recommend it for what you are looking for. Maybe the non-premium muffler is better.

I'm interested in a block/crank for a build-up too.

This was my experience exactly, except I was able to fix and use the crushed center cap with some superglue and a little good luck.

I've been biting my tongue a little so as not to hurt any feelings, but, two things: 1. The body styling on that car screams for a chevy 427. Sort of a Corvette Summer kinda feel. 2. And the price sort of whispers $12,500.

If you haven't already, dropping the mustache bar off of the diff will let the nose drop about 3-4 inches (put a stand under the diff) and the bolts are much more accessible. Without an impact wrench handy, this might a lot harder than with. I left the rear sway bar in place. Still, those four bolts are a pain to get at, but I was able to do it yesterday with two 14mm end wrenches, one of which was 6" shorty. Good luck.

http://www.youtube.com/watch?v=8iffDvXTcm8

Scrounging around for a washer pump/motor for a '75 280. I think most other year models would work also.

Just an ordinary rubber hose connector.

Does sound like an intermittent ground problem as srgrunz suggests. Just to rule it out, I would clean the battery terminals and double check the battery negative gounds to the chassis and starter. I recently killed an electrical gremlin on my own Z that turned out to be a simple battery ground problem.

FWIW, I wasn't able to find the Help! Chrysler hinge kit here in Anchorage so I went to Home Depot to see what else would work. Turns out a 1/2 to 1/2 brass hose connector works perfectly when you cut one side off and file a little off the center piece. Sorry I don't have a photo. I'll see if I can't post one later. Cost was about $3. Edit: Looks like this -

+1 for muriatic (sp) acid rinse. I dropped my tank today and did the acid rinse. $7 a gallon at Fred Meyer. Put a half gallon in and swished. Put the other half in and swished again. Acid went in clear and came out yellow. Night and day difference as far as the interior color of the tank. Tank actually started smoking and it may be better to diltute the acid a bit. Mine was 20% concentrate. After the second rinse I washed the tank out with water a few times and drained again. Poured in a pint of HEET (water emulsifier) and a few gallons of gas to get to the gas station. Started right up and and didn't to miss at all, though it smoked white for a few minutes as some water burned through the engine. If your tank hasn't been out before, be prepared to re-plumb everything and buy new clamps. Took about three hours including several trips to the store.

Rota RB 16x7 w/205-55-16s. Sorry for the ghetto pic. We're having breakup in Alaska and the roads be very grimy.

Finally got around to wiring the MSD 6A unit as a stand alone ignition yesterday. MSD adaptor 8910 will work as described in this thread, particularly in andrewgore's final post. (Here: http://www.classiczcars.com/forums/showthread.php?t=22166) Stock ICU went in the trash. Hopefully this might be of some use to others trying to do the same thing. Next step is fuel only MSII. Here is the Green Hornet with new Rota Rbs.

Thanks giorgio61. MSA shows out of stock. Bought one off the 'Bay today for a couple bucks more.