Zed Head

It might be tunable with some tricks, and timing adjustments. Just be ready to make some changes. And don't forget that noise and power might not offset gassy smell and dead spots in throttle action, for your wife, like they might for you. Should be interesting.

Pretty clear that you've already decided... You haven't said if you've even driven the stock N42/N42 engine with dished pistons and 8.3 CR using the 1976 EFI system. So if it doesn't run right you won't know if the EFI system is out of whack or if it's the modifications you're making. You're going to end up with many unknowns on a primitive EFI system. Could be fun if you like solving problems, not so much if you like bolt on and go projects. I'd be interested in how the stock EFI system handles those changes but it will be hard to tell what's causing what. Good luck.

"green-eyed Lillith" brings up some interesting search results... So, it's looking like the loose pivot lock nut is the cause? Still curious. Not really clear how you received the head or what you did to it before driving. You have the most interesting thread going. My biggest problem right now is working up a way to modify my heater coolant control valve so I can fine tune the heat output (I have one of those Honda valves but small movement lets lots of coolant through), and waiting for a small oil leak to drop the oil level low enough so that I can add some seal conditioner (my leak-free engine started leaking). I might watch most of the game then leave for the last 5 minutes, like I did for the NFC Championship game, when they were sucking.

Bummer. Is that really a colonoscopy camera? I want one. Did you check any other cylinders? Still curious about cam timing and valve clearance. Although getting the rocker arm lodged on top of the retainer as it wiggled its way out seems reasonable also. There was probably a short period of time where the valve was still held up by the seal when piston damage could have been avoided. Sorry, I'm sure that doesn't make you feel better. Don't forget though - the Seahawks are playing in their second Super Bowl. A little bit of feel good. Unless you're from Wisconsin.

Since you're redesigning you might consider the battery as just another load and run a fused line directly to the maxi-fuse block. I think that connecting the alternator charge wire to the starter lug is just an inexpensive and convenient way to connect it to the electrical loads, for the automakers. That is actually two unnecessary junctions between the alternator and the loads. Each one drawing a few milliamps. I moved all of my connections to a central post, and run a separate 12 gauge wire to the battery for charging. The big cable is used to run the starter, and the wire from the alternator is connected to the central point. So after the engine starts and the alternator is charging, the current flows directly from the charge wire to the various loads, even the EFI harness power. My battery terminals have no extra wires attached, except for the ground wire on the negative terminal, and the starter only has the big positive cable. Just one way to do it. The connections all stay clean and uncorroded because they're not exposed to the acid fumes from the battery. Even the maintenance-free batteries vent a little bit.

BRAAP's writeup says a lot more than just a statement about cylinder heads. That's a gross over-simplification. I think that where people tend to get misdirected on "performance" is in focusing on peak numbers. There are many ways to increase the maximum power that an engine will produce but, with the stock EFI system, it will probably run poorly everywhere else. Most of the tuning that is done with aftermarket EFI systems is "everywhere else", to make the car drivable. Lean spots at certain RPM will make the engine balky and weak at certain times, rich spots will make it stink and might foul plugs. I have an essentially stock setup, and I rarely get the engine above 5000 RPM, where max power would be. What makes mine a pleasure to drive, for me, is the way it pulls cleanly from idle at a stop light up to the next shift point, and the way it responds to throttle from cruising at 2,000 - 2,500 RPM. Or the way it cruises at 3,500 RPM if I want a little more jump when I hit the gas. Almost all of the performance stuff you read is race-focused,which is mostly wide open or closed throttle. Many people say that adding a tunable EFI system to the stock engine parts will add more "performance" than adding parts to the stock EFI system. Even higher peak numbers.

You could pinch the hose to the booster and listen for a change in idle speed. Or disconnect it at the check valve and block it and see if idle speed is different than when connected. Might be difficult to pinch shut the old stiff hose.

It needs something to make and break the circuit to the coil. Either points or a module with a triggering device. They would all have two wires though so your picture and description aren't very helpful. Sorry. Take a picture of the top.

Semantics. It's actually the rocker arm pivot that is self-adjusting via hydraulic pressure.

New valve seals would probably hold the valve up while the retainer got pushed down by the offset rocker arm. Still curious though, that the engine ran so poorly. It's common for people to test an engine by disabling an injector or a spark plug. Sometimes 5 doesn't sound a lot different than 6. And I've seen several accounts of people driving around with an odd noise only to find out later that a rocker arm had fallen off. His symptoms seem more severe. From the work-rate shown in his prior posts I'm assuming that the head is already removed and/or the problem has been fixed and he's out driving again. We're having good weather here in the PNW. Not a good time for the car to be down.

Odd. It should have kept running on 5 cylinders. Better check your cam timing, Maybe the sprocket's loose and you sheared the sprocket dowel. Might explain a piston doinking a valve, and the fact that it wouldn't keep running on 5. I hope DPLLC didn't send you cam with a bad dowel (I just can't let the guy off the hook yet).

According to Honsowetz (How to Modify...) the max valve lift for the stock valve springs is .460". The valve seals also have a limit, which requires either an "A" type seal (not 100% sure what that means, vague memory) or Ford valve seals. Can't remember the details on the seals. Anyway, it doesn't look like a drop-in, it will take a little extra research. You've changed the topic of the thread, but it looks like you're now planning a high lift cam with flat-top pistons. It would pay to verify valve clearance with the piston tops. There might be a problem there too.

I think it depends on how far you let things go before. Some people recommend just scuffing up the pressure plate and flywheel with sandpaper if there are no grooves or heat-check spots and the surfaces are still flat (checked with a good straight edge). Monroe describes it in his How To Rebuild book. AS for where to get them, RockAuto has a good selection, the auto parts stores still stock them, and Nissan dealers may still carry them also. After sanding the two metal surfaces, clean them well with brake cleaner. You'll need to know the size of the pressure plate and flywheel. But the disc itself fits the transmission shaft, so that's what matters, aside from friction surface size. I've sanded and cleaned a flywheel surface with no issues, using a pressure plate and disc kit. 30100-Y6800 http://www.courtesyparts.com/clutch-dis-p-329045.html (225 mm)

http://iraggi-alternator.com/support/index.htm

Most of the guys that have built engines will say that the slight bump in CR, and the headers won't improve performance much at all, on their own. The CR increase will make the engine more likely to knock, even with 94 octane (does Canada use the same octane rating as the US?). The stock exhaust manifolds are pretty good. The P90 head might flow a little more air than the other heads (the square unlined exhaust ports), but not much. The fuel rail and the injectors certainly won't do anything at all for performance. You'll need to find some injectors that match the stock injectors almost exactly or you'll screw up the ECU's fuel control. The aluminum Pallnet rail will probably help with the heat soak though, so that's an improvement. But you can do that with the barbed injectors. Most of the changes you're planning won't add much over stock, and will cost more money and complicate things. What are you hoping for? A rebuild with stock parts would probably get you the best running and most dependable engine, using the stock EFI system.

You need to make the drawing match the alternator. Looks like someone wired a GM alternator for "one wire" operation. This link might be useful - http://www.hotrodlane.cc/ONLINETECH/CS130DREG.html Here's another - http://www.dynamo-bg.com/en/res/files/22/CS130en.pdf Can't find any "A" or "B" labels.

Apparently those "horns" are for Noise-Vibration-Harshness (NVH) damping. If you have a ZX transmission you can use them. If you have an early transmission there's no holes for them.

211.9 cents/gallon for 89 octane in the Portland Metro area. And they fill the tank for you.

Someone, I think Tomohawk, asked a while ago about how many seals it takes to do a whole car. Looks like you used a front door seal (http://www.kiapartsnow.com/genuine/kia-wthstp-frt-door~0k01858760b.html) to do the hatch, is that right? So three door seals will do all three openings, but a person might not want the Kia Sportage hatch seal. I didn't think a door seal would be long enough for the hatch but looks like I was wrong.

I only have 280Z and 280ZX pulleys. I'll be keeping my eyes open in the wrecking yards in the future though.

There's a whole big thread on Hybridz about the LD pumps. Apparently, the original LD pumps pushed more coolant so people wanted them for their performance engines. But they don't make them anymore so the parts places are selling the gasoline pumps as LD pumps, or getting them mixed up. There are subtle differences in the pump body and blades. Some people ordered LD pumps and got gas pumps, some got LD pumps. And, for a while, the cast impeller pumps were hard to find,m apparently, only the stamped impellers were available. And they weren't very good. That's all I know. I'm always looking for easy part swaps though, so if a cheaper L4 pump will do the job with just a different pulley, that would be neat. The main reason I posted...

It would run like a turbo L28, off-boost. Probably okay. 17% more displacement, and bigger valves, might make up for the lower CR. There are general formulas out there that try to estimate the benefit of increasing CR. Here's one - http://www.wallaceracing.com/hp-cr-chg.php Doesn't look like much loss. This is one of the basics of the argument people make that optimized ignition timing is far more important than a few extra CR points. The added displacement might actually increase power. The engine will sound a little dull though. The exhaust won't have that rippy sound that high CR and a performance cam tends to give.

That narrows it down. The LD28 pump is typically used by people that want more coolant flow. The cast impeller pumps are commonly available though for the typical L28. The LD thing confused me. Still not totally clear though, to me. I think that you're saying that the height of the water pumps are different, putting the pulley mounting flange closer/farther from the front of the engine. You didn't say specifically but it looks like you're assuming that the L$ pump impeller will fit the L28 timing cover and bolt up correctly, and the only issue is the pulley mounting flange offset. Anyway, looks interesting. If you supplied some measurements people could check their pulleys. Short answer, for me, is no I have not tried this. I do have some L28 pumps that I could measure though. As I said.

There was a guy on the forum a while ago that put either a P79 or P90 head on a block with dished pistons. Said it ran fine, but it was his daughter's car and he was just getting it running so he could sell it. It was an EFI engine. Assuming the engine itself is in good shape, your biggest issue might be getting the SU's and intake mounted and the carbs tuned. I don't know if the P90 heads come with carb manifold mounting holes. I think that the other heads, N42, N47, for sure, and maybe P79, do, but they're designed for NA. The P90 is a turbo design, so no need for carb manifold holes. That's probably your decision-maker.

Not a big deal in the big scheme but the later 240SX's did get the reverse synchro. It's shown in the Motortopia link above (copied specific below), and in the FSM's (baulk rings for 5th and reverse, 1996). Of course, Nissan kept the 240SX name but changed the platform from S13 to S14, so that's different. The Z31 71C's had some improvements also, like double synchro rings for 2nd gear, some years even had double rings for 2nd and 3rd. The cases are the same though, so the swap procedure works on any of them. Don't know about the Z32 versus Z31 stuff. People tend to call this a bellhousing swap but it's actually a front case swap. If you're from GM world, a bellhousing is completely separate from anything that holds gears and bearings. It is essentially an adapter for the trans and engine, and covers the clutch, flywheel and input shaft, In the procedure being discussed here, the part being swapped is precisely machined and contains the bulk of the gears and bearings. The "T5"'s use a separate bellhousing, I believe, but that's a completely different transmission and manufacturer. http://www.motortopia.com/cars/1973-datsun-240z-11118/car-pictures/240sx-transmission-swap-14041/IMG_2766JPG_Thumbnail1.jpg-412263