Muskrat

Thanks for the reminder AK, I've actually been trying to keep detonation foremost in my mind when choosing injection components. The 450cc injectors and megasquirt should be up to the task (I hope).

I made a few assumptions when I did the calculations. The main one being if they use 240z rods due to a shorter piston pin height, and are already flattops without valve reliefs, that they will be near or below zero deck height to avoid valve contact. Of course, I've been horribly wrong before when making an educated guess, so who knows? **Edit: I used the Sydney Z car club engine calculator, and assumed a .030 positive deck height of the stock Z pistons and a 87mm bore with a true flattop piston. It spit out 8.16:1, which I rounded up to 8.2:1 because I'll more than likely have the head surfaced a tiny amount to assure a good headgasket seal. If anyone has actually installed the AZC pistons and measured the final deck height of the piston, by all means post your findings.**

I was looking at the AZC pistons because they're conveniently pre-packaged with rings and pins. I would actually like to use a flattop piston for this setup paired with a 2mm headgasket. If my math isn't wrong, that should put me around 8.2:1 compression, which seems perfect to me. As far as use, I'm looking for 350rwhp in something I can drive to work and back for grins, and then make the hour drive to the 1/4mile at Ennis afterwards.

I probably should restate my question: Has anyone had good luck with the Arizona Z Car forged pistons, or should I be looking into another brand or manufacturer?

Well, its been quite the long time since I've last posted, but I'd like to make sure I'm not forgetting something critical or have a bad parts mismatch before I progress much further. The car started its life in my posession with the origional 124k L24/E88, which I later swapped out for a homebuilt L28/N47 setup with SUs, header, and full exhaust. After the high compression NA motor died from a combination of critically low oil levels and my own stupidity, I started collecting parts for what was supposed to be a stock L28ET swap. Being horribly afflicted with 'while i'm at it syndrome' as I am, it quickly became another massive project. **Edit: I should probably add that this is a weekend/track driver that I'd like to make 350rwhp on, reliably, cruising to work and back.** My main concern at this point is the internal engine components that I origionally intended to clean up and reuse, namely the stock turbo pistons. I'd very much like to upgrade to flattop forged pistons and a 2mm metal headgasket. The block itself has already been to the machine shop once, I don't mind sending it back to get the bores resized, and the block surface decked. Should I just look away and leave the stock pistons with new rings in the block, and run it as is, or strip the engine down again and rebuild it with Arizona Z car forged pistons and 240z rods? Internals: * ARP 9mm rod bolts, 12 point head studs, and main studs * Nismo timing chain set, with cam gear * Clevite .25mm main and rod bearings Turbo conversion parts: * Megasquirt running MSNS extra software and upgraded MAP sensor * Zeitronix Wideband oxygen sensor * MSD 6A * manual boost controller * 60mm throttle body w/ ported '75 intake manifold * JSK fuel rail and TB spacer * adjustable fuel pressure regulator * intercooler, bar and plate 18x12x3" core * 40mm external wastegate * SST hybrid GT35R/ T3 turbo * 2.5" mandrel intercooler piping, silicone couplers, T-bolt clamps * 3" mandrel exhaust, Magnaflow muffler and Dynomax resonator Drivetrain: * solid front differential mount * urethane transmission mounts * 81 nissan 5-speed transmission * Exedy 2100lb clutch kit, sprung organic disk * Fidanza 10.5lb 240mm aluminum flywheel Fuel system: * LT1 Camaro gas tank and evap system (I got it for free, can't really complain) The head is going to recieve a light cleanup and port matching before going to the machine shop to get a valve job, light surfacing, and new stem seals. I do have a pair of spare heads to practice on first. If anyone feels I'm missing something critical from this setup or have any concerns, please voice them. I've taken my time getting this together, and I'd like to get it right.

Finally got around to purchasing my Zeitronix wideband setup, once I get it up and running I'll let you know how it works out.

I am also running the crackishly large 40mm Stonemountain wastegate.

I'd assume .010" undercut on both the main and rod bearing journals.

I believe thats the spec for the stock main bolts, I have ARP main studs installed, wouldn't the torque required be different?

Anybody?

Well, finally got my engine back from the machine shop, and after waiting almost a week for the piston rings, I'm ready to start assembling my motor. I'll be going with the 55ft/lb rating with oil everyone seems to agree on for the ARP head studs. The spec that I can't seem to find, however, is for the ARP main studs. Does anyone out there have an idea?

The 'how to rebuild' book really is an excellent resource, and at $20 US, its well worth the money even if you only use it as a handy reference.

Its too bad we sold that '73 convertable that we rebuilt, it had a 351c with 4v heads, Weiand X-celerator intake, headers, and a complete MSD ignition system. Actually.... I'd steal the 9" and C6 trans too, 351c drag Z anyone?

72 240z megasquirt Explorer 302 single pass mounted turbo, flipped shorty headers goal=400 rwhp. Ford T5 R230 rear I also would be interested in mounts and trans mounts only, but would like a bit of infomation on where the motor will sit in the bay relative to the Alsil kit. Also, with your fabbed mounts will the motor clear the steering shaft?

Fixed. I love compound problems. The positive trigger wire for the ignition module was faulty, and the section of wire the previous owner had crimped in to replace the ballast resister was corroded beyond belief. As for the carbs, there was some gunk on the floats, and some more gunk on the pistons themselves, making them stick badly. Cleaned everything up, and fired the car at around 2am and took a victory lap around the block. My neighbors hate me.

Well, its looking like the problem is twofold. I'm no longer getting spark, which I'll try to troubleshoot tonight. This doesn't explain my previous lean problem though... I'll have a look at the floats like you said Sho-Z. Thanks for the tip.

Oh, I know the throttle shafts have a vacuum leak, but I'm relatively certain that's not the problem, as I've been running the carbs as they sit now for 2 years.

To begin, I have a '72 240z that I've swapped a 2.8 motor into. Its got a N47 head, flattop pistons, header, and I'm running un-rebuilt roundtop SUs with an electric fuel pump and clearflow fuel filter on the factory gas tank and lines. I also converted to an electronic 280zx ignition. The coil, wires, and plugs are all less than a month old. This setup was running flawlessly for several months, burning a little bit of oil (a few cracked valve seals, nothing major), but otherwise pulling fine. As of about a week ago the motor had between 140-150 compression on all cylinders with the throttle closed. The problem started around two weeks ago, and about a week after running a big can of fuel system cleaner through the motor (probably unrelated, but I dont want to leave something out). At the time, the problem was limited to the motor leaning out after a long gear pull. It's been progressively getting worse over the past two weeks, and now the motor idles very rough at 500rpm (previously a nice healthy 900), and will pull for short bursts before stumbling and misfiring badly. Oddly enough, until today (problem is now even worse) I could use about 20% throttle to get me to work and back, and the car would cruise relatively smooth. Now, the car will barely move under its own power. After pulling the spark plugs, I saw that except for the cylinder that's burning oil, all of the plug grounds were WHITE. Not yellow with white flecks, but for the most part, uniformly white. I've tried my best to eliminate potential causes for this worsening condition. The fuel pump was replaced yesterday, the fuel filter is clean with no debris in it, I checked fuel flow at both the inlet to the fuel rail, and the outlet. Both had a pretty good amount of flow. I have no way to check fuel pressure at the moment, but the car ran fine before with the same model pump I replaced it with, so I doubt thats the issue. Most of the ignition components are new or less than a month old, and the vacuum advance on the distributor is connected and working. An odd thing I think I should note, I drained the fuel bowls to check for any trash (didn't find any) but I did notice a rather small amount of fuel coming out of both bowls compared to the flood from when I drained them to swap them from the 2.4 to the 2.8. It almost seems to me that the fuel bowls aren't filling up fast enough to support anything more than cruising and light throttle. So: I figure I'm looking at a fuel system issue somewhere along the lines, probably in the carbs. I do, however, have a hard time believing that both carbs would fail in the exact same manner at the same rate. So I'm stumped, hoping someone out there has had this exact problem and can tell me what needs to happen to make it right again. This is my daily driver, and at the moment, it doesn't run at all.

Well, if you don't mind loosing the relief valve, your local nissan dealership has an 'aftermarket' solution called a pipe plug. Just tell them which hole you want to block off, they should be able to find you the right part. Failing that, have a look around your local hardware store.

I would like to add that the red DZ302 equipped car that Zfan mentioned is set up for roadrace, has 315 rear tires, and as a manual transmission car gets NO traction at low speeds.

Ferd, I noticed you're local. I tried dropping you a PM, but for whatever reason the system is giving me a strange debug error. At any rate, would you send me an email at Muskratcentral@hotmail.com. I'd really like to talk to your about your swap. I hope it will live again!

I think I'm going to be sick. Edit: Now I'm sick. It does have 4 exhaust pipes!

Sounds like the PO did some creative rewiring. Easiest first: The headlights are fairly easy to replace, you'll need a medium sized Phillips head screwdriver and a flashlight. On the back side of the headlight to be replaced, you'll find a metal case held to the headlight bucket by 4 screws. Undo the screws, but be careful, I almost broke my old light because I wasn't holding the case when I pulled the last screw. If replacing the light doesn't fix your dim headlight problem, I would strongly suggest looking into the 'headlight relays' modification. I'm running relays for the headlights on my car, and you can instantly tell the difference, especially if your stock underdash wires are old and have corroded connections. This is a fairly simple mod, Pete Paraska had the instructions and a wiring diagram on his website the last time I looked. I, personally, would avoid stepping up to an HID kit until the insufficient factory wiring has been taken care of. Hope that little bit helps out, I'm fresh out of information on the other 3 problems.

Oh yes, thats getting forwarded to my DSM friends.

Thats not nasty! Thats priceless!