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Daeron

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Posts posted by Daeron

  1. 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.

  2. 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.

  3. 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.

  4. 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!

  5. I want to get rid of all Electrical Things That arent Needed just the basics lights,dash lights, wipers, and so on. I was Searching But dont know what to type to get me where i want to go So if anyone can point me to the right direction i Would Appreciate it........ I Will post some pictures later

    :redface:

     

    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.

     

     

    :ass:

     

     

    "The basics" is about all the electronics this car ever HAD.

  6. 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 :D

  7. 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.

  8. 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:

    Follow me here if you will.

     

    If you are starving the jets at 4500 rpm, and did not know why...you would put in larger main jets to compensate...We all have fallen into this trap...Large main jets...add 50 for the airs...then run out of gas at 4500rpm.

    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 :coollook:

  9. 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.

  10. 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.

  11. 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.

  12. 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!!!!

  13. No, I wouldn't recommend pulling the head... if you are seriously a novice the intake/ehaust gasket job alone is a great enough challenge, but be aware that the primary problem with working on your own car is NOT, "Can I do this or not?" The issue is, "Can I cope with the potential complications that may arise when I do this?"

     

    Taking the intake and exhaust off of a stock L28ET is a pretty respectable chore to take on as a novice, but it shouldn't present TOO much difficulty if you have the tools and initiative... Label everything, bag your bolts according to what they came off of, label everything, maybe get some nice colored tags so labeling everything is a bit easier, and while you are at it go to xenons130 (or something like that) dot com (just google it, I never remember the specific URL) and download your FSM if it is available.

     

    BUT, beware that you may break a stud off, round a bolt head, or do some other asinine thing that could complicate matters. Take your time, and if fasteners don't yield to your wrench, don;t get stupid. Make sure you have your wrenches squarely and solidly on all bolt heads or nuts before applying serious torque, make sure you have the RIGHT SIZE (some are 12mm, some are 13mm when dealing with intake and exhaust; NEVER trust any rule on which is which, feel the wrench on the nut!)

     

     

    But honestly, with patience (and with the aid of poverty, I am right there with ya buddy) this job can be undertaken by a newbie. Just search around and read other peoples stories, see what PROBLEMS they ran into, and find the best way to anticipate what might come up on your car. Learning from other people's mistakes saves alot of time :burnout:

  14. That photo makes three Hybrid Z'ers I know of that do all their automotive work in flip-flops! :-P

     

    Add to that list Cobra_tim (me brudder) and count my old man for my citizenship. My uncle, half the time says "You guys, and your safety shoes!" and the other half of the time he cannot because he is guilty too.

     

    I prefer to be barefoot, period. Flipflops are my best friend due to the compromise; I will NEVER wear them to the shop. I value my little toes far too much, and soccer players by their nature take care of their feet. You don't see a masseuse working with a hammer often, do you? :-D

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