Daeron

Pull all the spark plugs. Get a 1/2 inch breaker bar or ratchet, and a 27mm socket (i THINK) and try to rotate it using the crankshaft bolt. Don't mandhandle it! without the spark plugs in the only thing you are working against are the valve springs, and the force they exert is MINIMAL so the engine should spin freely by hand. If it doesn't, you have a problem. Pull the cam cover off and look at the valvetrain and timing chain. Try removing the starter and spinning the engine as described above, while inspecting the flywheel ring gear through the starter hole. If all that checks out OK, try getting a pencil and probing each piston through the spark plug hole checking for issues.. but if all that checks out and you are still binding chances are something is seriously blown. IF the engine spins freely, try using a screwdriver to "hotwire" the starter by bridging the connection between little solenoid spade terminal, and big red battery terminal. If THAT magically starts it like butter, then you need to install a new ignition keyswitch, or a pushbutton starter switch, or a relay signaled by the existing solenoid wire to activate the starter.

I like front airdam, no side skirts, stock butt, 240 chrome bumper. Preferably with either a one piece spoiler (BRE style or molded to the hatch,) or a three piece molded spoiler, and rear louvers. Get the DATSUN or 280/260/240Z black stripey decals that go along the rocker panels if you need something going on down there.. but the front airdam and the rear spoiler are my favorite LOOKING "aero mods."

Yeah, thats right, they were from a Ford. All I could remember was that they were not the standard material.

I predict you wind up sticking with an L-series after all this learning about it.

It will be nice to see the before and after pics. A clean, well tuned, and de-smogged, but otherwise bone stock L26 isn't a very common sight, especially not on this site!

this is one of those threads we have ALL read.. so some reaction was ajudged needed by yours truly *bow*

Awesome, did this engine builder have any guesses as to which casting it is?

I hope you took that in the right light Well, basically, IF what is there, in your car, is solid, then it is useable and simple enough.. If you can remove the dashboard from the car laying it out is a fairly straightforward process.. at that point you can evaluate it, and decide to reuse it with repairs/upgrades as needed (such as relays for headlights and starter circuit, intenrally regulated alternator, ammeter shunt bypass or upgrade) or just get a painless. In the end its basically a question of whethewr whats in the car now works. If so, great, use it. Relays and fresh power supply makes your headlights brighter and switch last longer, and internally regulated, higher amperage alternator swaps abound, and include instruction on installing fresh charging wire, etc. If it doesn't work so hot, it is easy to lay it bare and either fix it or scrap it. This car has a 280-style dash, right? I can't recall right now if early 260s had a 240 dash or if that's just false info i picked up somewhere, but I had a "280 style" 260 dash in my hands the other day, and the wiring on it is SO simple and easy to expose and dissect I was AMAZED!! My uncle and I were comparing it to the 5 240 dashboards that it was piled with and the difference was night and day. My dash (75 280) is far more cluttered with wiring than yours simply by dint of the EFI; this is one of the great aspects of having a 260 IMO.

uhm, I may be sending you after a red herring, but check out the valve seal installation job as done by other members here.. it may be a performance type situation that doesn't apply to you, but something in my memory is flashing a "complication possible here" sogn when I see those valve stem seals.

There is a subtle art involved in tweaking an old L-jetronic system to accommodate "hard" performance mods. There are very few inputs to the computer, and it makes its fueling decisions based on these. By changing the fuel injector flow rate and/or pressure (in other words, changing how much fuel you squirt into the manifold every time the computer says "open") and ALSO modifying the input signals from the air flow meter and the CTS to attempt to match your fueling to the way the engine breathes after your intake/exhaust/cam/port/polish/pistons. Unfortunately, since the car is equipped with at best a narrowband O2 sensor and a computer designed in 1974, you can't *really* know you have it tuned well without either dyno time or a wideband sensor and a gauge... which between them cost about 200 bucks. You can megasquirt an L28 for ~$800 if you take all the easy ways out, more like 5-600 if you do extra assembly yourself (both assuming you need pretty much everything; if you happen to have, say, a trigger wheel or ignition system you can re use, a GM MAP sensor, a wideband O2 sensor and controller, these things shave off of that rough figure.) Twenty years ago it was worth it to try and enrich your maf a tiny bit, and maybe install a potentiometer or resistor inline with the CTS to give it the right amount of gas... but the results were hazy, and the procedures were a shade more involved than many feel like working with electronics. This is why most people scrapped the FI and threw SUs, a 4bbl, or triples on the cars for so many years. Now replacing the stock FI with a MS system is at least an equally viable option. Find the EFI bible and read it through; it will teach you alot.

My thought had always been to throw the L20a crank into an 89mm bore N42 block with LD 140mm rods and KA pistons.. I have never (to my satisfaction) determined whether the diesel rods had a different pin. (according to this thread it appears so, for my purposes thus far I can ignore it) If it would pin together, it would produce a 2602cc motor with just over 2:1 r/s, 14.4 degree max rod angle, and using an E31 head and flattops, 11.2:1 compression. Yes, that is high compression, but with a massaged E31, or a massaged P90 (shaved, about the same chamber volume as an E31) and a good fuel tune, and factoring in the detonation resistance from the piston speeds, I think 93 octane might work? If not, small piston reliefs mirroring the combustion chamber to reduce a few ccs of chamber volume could drop compression down to a more manageable level. I wouldn't presume to try and tune this on carbs, and it would probably take a GOOD standalone with a GOOD tune and the right camshaft.. BUT as was said above, if it can be assembled from junkyard parts and tried out, the head and block can be re used with a different reciprocating assembly. If I can get the crank I pretty well have my heart set on building this motor sometime, just to get it done. I know that if it can be done right, I can do it, and I want to. Pre-RB, No D!

Well, the Mr. Fusion unit is easily unplugged and only secured by four 1/4-20 bolts, the radio telescope equipment unplugs easily enough, but it might take half a day to remove entirely (sure, it isn't a drain on horsepower when it is unplugged, but you don't want to leave all that dead weight in the car, yanno) and *some* of these cars had covertly installed ICBMs in the rear deck. (They WERE built during the Cold War, remember) Careful research on the web regarding "Freedom of Information Act" might shed some light on how to tell if your car is so equipped, but TBH good luck. "The basics" is about all the electronics this car ever HAD.

I cannot imagine a scenario where you would want to leave the suspension on, with the vehicle on a rotisserie. Access to the underside of a rolling chassis is accomplished through a lift (if you are lucky) or jack/stands; Rotisseries are for frame/unibody recon work.

I seriously thank all of you guys for sharing this... I grew up around twin and triple weber/mikuni/solexes on my uncle's cars, and cannot tell you how many engines and setups I have seen pass before me... but only in the last 4-5 years have I gotten into auto tuning as a hobby for myself (kinda thought it was beyond me before that, figured I would be half-fast at best) and there simply haven't been carbs in front of me.. So you are filling in the technical details that simply appeared to be magic tricks in front of my eyes as a kid, is what I am saying. Now next time the roadsters fire up, I will know what I am doing

Holy Ancient Thread Batman!!!!!

google the phrase "techtips datsun" and go to Blue's techtips page. Find the EFI bible. Download it and read it through at LEAST twice, even all the diagnostic tests. IIRC, the Bible says to check the AFM first. TPS wouldn't cause it to fall flat on its face; if the TPS was bad it would likely be open at all times, which is "cruise" mode (as opposed to "idle" or "WOT," the only other two positions the TPS can be in.) Cruise mode wouldn't fall flat on its face; it would run rich at idle and lack a little power (and possibly cause some detonation issues long-term) at WOT. google xenons30. (or s130 if you have a Z) Find the FSM for your model year. Find the Engine Fuel section. (If you have a model year without a complete FSM, find an adjacent model year, they are virtually all the same from 75 thru 83.) Find the fuel pressure test section. Test fuel pressure at speed according to FSM directions. I fix my car one procedure at a time. Until I have followed directions, I am fumbling about in the dark.

Mark: I think that what the Sergeant is trying to say is that the fuel flow into the jet well is not properly inhibited (by which I mean to say, OVERLY inhibited in this case) and that improper fuel flow characteristic, and corresponding variations in the jet well, causes you to "correct" other jetting settings in a manner that brings out your two rich "dead" spots. He seems to be saying here: that everyone is using jetting to band-aid over what is essentially a fuel starvation issue, but a post-float bowl starvation issue. I am really fuzzy on the carbs, so I may be mis interpreting, but if you look at the AFR graphs, you REALLY have to look hard for the rich spot in his setup, and his lean(er, there arent really any LEAN spots) spots seem to be his primary deviation from standard.. *maybe* he is slightly richer than ideal across the whole board. Again, I may be wrong, because I am in WAY over my head as far as the carbs go.. but I think I am understanding what he is trying to say better than you are. 'Course, I could be tooting in the wind, too

always been partial to Infinity Kappa 6x9s with EMItweeters. If you can set up a bo to set them at the right angle, the acoustics in the S30 are phenomenal.. I had my kappas rolling around in the back in boxes for four years and I could hear a world of difference between having them just sitting on the deck pointing forwards, and being propped up and pointing along the roofline of the car. That much would hold true for any 6x9 I guess.

yeah, seriously, first you are saying your mom won't let you work on the car at your house, it has to be running NOW, then you want to talk about turboing the car? That is how people wind up getting too deep into projects and screwing themselves over.

An L28 is an L24 with a different crankshaft and rods (shorter rods, longer stroke) and a bigger bore. Not THAT much bigger in any dimension. People "shy away from boring out L24 blocks" but only in the sense of boring it out for a ma displacement L-6. If I am not mistaken, the P30 block that is in the 73 car could be bored to 280 spec safely, and with the L28 pistons, and the crank and rods from an L26 (I could get the crank/rods for you, we have two L26 engines we were discussing stripping and junking today) you have a 280 motor. But that is all displacement. The BIG difference between the turbo motor and the earlier NA Z motors is the shape of the combustion chamber in the cylinder head. Have you read through the stickies regarding different cylinder heads? The P90 and P79 that came in the 280Zs (P90 being turbo and 79 being non) have large displacement (~53cc) quench style chambers, where the later 240 motors, 260 motors, and the 280Z-no-X motors had open chamber heads. EARLY 240Zs with the E31 head have a quench-type combustion chamber similar to the P-series heads. This is ALL a GROSS SUMMARY of things you need to know more thoroughly yourself before you make your decisions. The combustion chamber on the E31 head is smaller than the P-series, which means that the E31 out of the box would give you higher compression with the same bottom ends. (by the way, with either of these heads in an NA application you will want to be using flat top pistons, not the dished used in the early L28 motors (Z no X) and the turbo L28s.) So, in the end, my point is that there is no real serious difference between an L24 and an L28e.. nothing magical except displacement, and slight differences between the interchangeable cylinder heads. Some choose to take a P90 head and shave 0.080" off of it, using N-series valves and cam tower shims to fit the valvetrain geometry, and not need to bother replacing valves with larger than originals (something you would want to do on a stock E31 head. The later head also has hardened valve seats that tolerate unleaded fuel; pre-77 heads all had bronze seats.) But a motor with fairly high compression (9-9.5:1), an electronic ignition distributor from an early 280Z, (search) your round top carbs (ACTUALLY I just heard that the needles from your flattops, can be swapped into the roundtops, for a good street performance needle) and an appropriate cam will deliver you plenty of oompah for your little old Z car. Never forget: 200 horsepower is ALOT of power for a 2000 pound car. Yah, the Z isnt THAT light... but you aren't talking about a Cadillac here. Once you get to a point with carbs, a cam, and good spark, you can turn your attention to improving your car's handling and get alot more driving fun for your dollar than you will by going all the way to 2, 250, 300 horsepower on stock rear diff and suspension. Ask anyone with a 250 horsepower dyno sheet: they burn tires! Personally, I've always been happy with a motor that delivers a satisfying *barK* from the rear tires shifting hard into second and third; if I had to exercise utmost control to shift into third gear, I wouldn't be having as much fun.

You worried about the pistons at all?? A quick look at the pictures and I want to say you could just clean those nicks up and run the bottom end as is. I wouldn't necessarily say this so flat-footed, but you are wanting to swap engines anyhow, and the motor you are dealing with is (depending on how you look at it) either a 240 with the wrong stroke and rods, or a 280 with the wrong size pistons. In other words, a 260 motor isn't exactly premium for resale, so I wouldn't fret over it.

omg good guess for me, I just picked a line from a song at random.

If I was better at finding the right words to say, I wouldn't need to write these mother-lovin songs!

Somehow I imagine that was just something the guy did with his transmission jack to show off how light these new 'vettes are.... Incidentally, we just bought a nice asymmetrical bend-pak for 1500 and its going up at the shop tomorrow, w00t w00t I say!!!!

Oh My GOD thank you for this thread!!!!! It would be SO easy to get a little bottle jack, or even remove the ram from an engine hoist to incorporate into one of these!!!