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Daeron

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Posts posted by Daeron

  1. I dyno'd it ONCE.....

     

    ...It made 141rwhp at 4100rpms.

     

    I went and did the math. Thats about 180 ft-lb of torque at 4100 RPM, and if it held onto 165 ft-lbs all the way to 6500 RPM that would be just over 200 wheel horsepower at 6500. Even 165 at 6K flat is about 190whp. Sounds like enough vroom for a bolt-together Z-car for me!!!

  2. I'd love to find a 16v getrag (same as the one used in the E30 M3) unfortunately it's only 1:1 top gear, so It would be necessary to source a taller rear gear than something like a 3.54

     

    Pretty sure that autos, or maybe maximas or something with an R200 came with a 3.2x rear gearset.. unless your talking about using a german rear diff too

  3.  

    Thanks!! I had thoughts along these lines and wondered if my conclusions (presumptions) were absolute crazy, brought on by an incomplete (theory only, no actual practice) engine-building education.. or whether they might actually be right. Obviously I hadn't thought of everything Mr. Vizard explained, but all of my thoughts tended towards these directions.

     

    That was an awesome, awesome read!

  4. I think the discussion should focus on the ability to run TWO DIFFERENT cam profiles simultaneously. A mild cam on on pair of valves and a wild cam on the other pair of valves. That is where S130Z was going, I think.

     

    I had an idea that might be similar to the CVCC idea by Honda. Instead of injecting fuel and trying to optimize atomization, somehow create a high concentration of fuel vapor in a pre-process, and then blend it into the incoming air at the proper ratio. After all, it's the vapor that burns best.

     

    Its alot more than that, even...

     

    Instead of having "intake valve open" and "...close" and "exhaust valve open and close" as four distinct events within the engine's cycle, you can divorce the "big valve" from the "little valve" and crack a tiny, but high inertia port into a cylinder early to aid in flushing out exhaust gasses, and leave that valve open until the very very last microsecond before sealing shut. Then, on TOP of that, your BIG valve profile can be designed for adequate flowing of air, and could even be (itself) a variable lobe timing design.

     

     

    In a way, the potential of the concept seems much closer to an "ideal" otto cycle engine design. I've thought about this a time or two, but never in as much depth as this thread has already discussed it.

  5. I posted this in my build thread some time back: http://forums.hybridz.org/showpost.php?p=971311&postcount=21

     

     

    Also, can someone tell me how you put a name to a link.....I see it in peoples sig or in a thread...it will say click me or my build or something like that and it brings up a link.

     

    In the text editor there is an icon that appears as a small globe with an infinity sign laid on top of it. Mousing the icon over the button and resting there momentarily will reveal a label that says "Insert URL."

     

    Type the text of your link, Blah

     

    Highlight it, then hit that button and paste in the address you wish to link to.

    Blah

  6. Sometimes when im filling up at the gas station, or if im talking with someone and were next to my car, I always wish I had kept at least the rear bumper. I never really realized how much I used them till they were gone. I especially miss being able to sit on the while taking a break from working on the car...

     

    You Ain't kidding, though!! Those asinine things were SO MUCH MORE USEFUL after I put them on than they were before I took them off. I have a 75 and I DDed it for almost a year before pulling them off (rear brackets left intact, nodoby wanted to get too close to my tail :)) About a year before my car went PFOOOF a cop pulled me over for not having bumpers on the car. (Actually, I went to jail over a warrant for failure to appear in court for a driving on suspended license charge that I had thought was already dealt with! so lesson: remove bumpers, could send you to jail!!) Anyhow, after that awful 24 hours, I got out and went to put the bumpers back on, and shortly thereafter I didn't know how I lived with my car without them. A somewhat ratty, daily driven 280Z DOES look uglier with its bumpers left intact.. but until I get going on other aspects of the car, the bumpers are not a huge concern for me anymore.

     

    Just ask Pavlov why. Bumpers off, go to jail, Shawn no take bumpers off again!!!

  7. So, can one assume that by increasing the opening point (temperature) of the thermostat, there is more time for the coolant to absorb the heat from the engine whilst also maintaing a higher coolant pressure in the coolant passageways around the block and head?

     

    Or does it make a difference at all when the thermostats are open in both cases?

     

    Point: Colder water absorbs heat more rapidly on contact than warmer water. the greater temp differential, the greater rate of heat transfer.

     

    Point: Any thermostat, or even a thermostat gutted into being simply a restrictor plate, acts as a pressure differential point in the cooling system. The pressure is higher "before" the thermostat than it is in front of it, because the pump works against this restriction and is pushing water through the engine into the thermostat housing, through the restrictor. So even wide open, at a colder temperature, a thermostat in the housing is MUCH more than pulling the thermostat altogether.

     

    Now, my thinking is, I run the lowest T-stat I can find (because I have read the points braap made above, made by MANY others, and also because I live in S. Florida. Its 83 degrees out right now on December thirteenth in the rain at 2 AM.) and use the coolant with the highest rate of heat transfer that is practical in the situation. That Thermostat, even when wide open, restricts things enough that the constant flow of my water pump (often at high RPMs) is inducing plenty of pressure at the high point, which is the system BEFORE the thermostat.

     

    I don't know how much weight you want to put in my experience; I said "practical" about coolant before because most of my L6 miles driven and owned are on a bone stock N42/N42 L28E and "practical" meant "water. I can always flush the thing out, and its gonna get rebuilt eventually anyhow." :shock: But my points stand.

  8. To the mild level I currently intend to build this, the RPM and power levels are such that decent cast pistons would survive. Budget will dictate the level of crazy this build will take on. (Plans could easily change depending on what parts become available that will tolerate regular blasts to higher RPMs, i.e. 7.5k, 8k, 8.5k... ). :wink:

     

    I've been fairly certain that you were fully aware of this the whole time, Paul, but my nature forces me to make abundantly clear the following point:

     

    Your rod selection is the important bit. I would be cross-referencing all the piston and rod numbers I could get my hands on, in search of a rod compatible with both a cheap cast piston, and a nice, possibly higher CR forged piston. My thinking is, you can match your rods with your crankshaft and block (ie BE bore, thickness, and rod length) and stop thinking about rods, when you find the rod to use that gives you two alternate piston choices.

     

    Like me: I wanna build a big bore, short stroke, long rod 2.6 based on a L20A crank. I wanna do it for s***s and giggles. I could use LD28 rods, and KA pistons. If it winds up failing to meet any of my expectations, I wind up switching to shorter, L24 rods, throwing in the LD crank that came with my rods (:icon56:) and keep the KA pistons and poof, there I am. Same block, same pistons, diff rods and crank. You would obviously jsut need to switch the slugs, but the concept is the same. Build a concept engine with failure in mind, so that if failure occurs, the next step is easy, and if failure DOESNT occur, then the next UPGRADE is easy.

  9. Also, if I understand the entire argument behind the higher-quench heads, the ultimate extension of braap's point is that with a more ideal combustion chamber (shaved P-series) you would still be at a similar compression ratio as your 44cc N-series, but this change in cylinder head design would allow you to advance the timing further, tuning the car into more power.

     

    The key element is "tuning the car into more power." More than your measured power output at 10:1 compression presently. There is power to be found with compression, and power to be left behind with timing. The cylinder head change might not itself be enough, the cooling mod might not itself be enough, the entire affair may well in fact be a Quixotic attempt chasing a theory that works better on other motors than on ours (in which case, Pete, your setup might well be preferred simply for ease of dialing the power in.)

     

    The actual combustion characteristics of the different heads, and their effective contribution to detonation resistance at high compression, are up for debate. But if you could get a head/piston combo on there that gave you 10.x:1 compression and let you run 93 octane to dial in higher advance, you would see more power.

     

    Edit:

    Awesome Freakin Thread!!!

  10. Can I ask what the large silver cable (with what looks like an inline fuse) is doing? Looks a like it is joining a distribution board and a small wire.

     

    Looks like its just an installed power tap for a possible future sound system or large draw device, or maybe an input of alternator power. the two small red wires behind the large wire head don't look to actually go into the top, and it also looks like the bus terminal is all empty at the moment.

     

    Also, he said "Almost done from the left: constant hot 12 volt distro" or words to that effect. I just noticed that, myself, going back and looking a second time, though. So obviously we all miss some little things :icon56:

  11. Next, The 440.00 dollar harmonic balencer from BHJ has failed. They make the hubs out of alluminum. I should of cought this before I installed the unit. You cannot have a press fit of about .002" from the ID of the harmonic to the OD of the crank snout, with the hub out of alluminum. When that crank and snout and the harmonic hub gets to 200 degrees, you loose all of that press fit, for the reason of material exansion difference in rates between alluminum and steel. From my calculations, it becomes .002" clearence at that temperature.

     

    Thanks for the all-encompassing update on the engine. You seem to have listed the same number twice here, and I am not sure if that was purposeful (and you didn't list a preferred tolerance) or if it was a typo, and the first number was intended to be a more ideal relative sizing.

     

    Since your opinion as a machinist and hi-po L6 builder is respected, I wanted that a little clearer for future reference. Obviously this is all in regards to 5-600 hp + machines, but the better the data, the better the HybridZ... right?

     

     

    Incidentally, are you planning on using another stroker crank at 87mm? Or were you going to try the head out on a more stockish, 2.8 liter setup? If I were in your shoes, I would be wondering if you might be able to eke the same power, with greater reliability, out of less displacement and more boost (when wanted, of course.) The answer to that question would be one benefit of the experiment, but it would also give you an opportunity to try out your new thrust washer design without risking another diesel crank.

     

    Just my thoughts. If you haven't figured me out yet, I have always believed that there was no such thing as a bad idea, because any idea can shed light. Even ideas rejected entirely draw boundaries.

  12. WOW that was a lot to digest.... Thank you for your input, this is a thread I plan on re-reading in the future and it seems like you just added about a metric sh!+load to it...

     

    I am for some reason stuck with this preference for MAF based systems, and I have no rational justification for it (whatever justifications MAF versus MAP have, I have no personal experience to make any argument worth dingo's kidneys) but that has been the reason I have kept this idea in mind... and you point at the Maxima that had twin butterfly TB's, which touches on another idea I have had...

     

    so like I said, thanks!!

  13. IMG00385Medium.jpg

     

    "Shoehorn: Its whats for dinner!!"

     

    "There were these things he had to do..."

     

    "Fat guy in a little coat.... Faat Guuuy in a liit-tle Coo-oat......."

     

    "Sitting to my right, the Jones family, 1, 3, and 5! To my left, the Robertsons, 2, 4, and 6!! Welcome to the Feud!!"

     

    "Because it was there"

     

    That picture just deserves words, and pondering.

  14. Man, a guy can't get aways wit nuttin' dese days wit all da coppers 'round watchin' all the time...

     

    I poop freely, like I write...like a sheep that got into the peach orchard.

     

    I just had to point at the butt you drew.

     

    (I always was mature for my age!!!!1!)

  15. *Just to note: i was in no way attempting to devalue the work that was done in balancing, its very good work. I admire his patience and fortitude in doing so! There is definately something to be gained for all of us from his work. But i was just highlighting some details that needed clarification, by bringing abit of science to the table. Sorry, i am doing analytical chemistry at the moment, affectionatly dubed "anal" chem! lol

     

    oy...

     

    But then again, tony highlighted your * nature and then included a parenthesized exclamation point, which is an old keyboard rendering of an arse....

     

    *(I couldn't actually say anal there and infer it as your nature. Seemed too forward. Woops.)

     

    But seriously, we like people who spell things out here when they speak accurately. (Or was that precisely? hmmmm....)

  16. I read those links. The thing that is outstanding is that blaming oil for bad engine work (or a bad custom muscle engine build) just too easy to pass up. If it were true that it was the lack of zddp that cause their problems, don't ya think that it would be true all the time in similar engines and catastrophic in less than 1500 miles all the time in similar engines?

     

    When my reality conflict with internet reads, I choose reality.

    I buy the cheapest non-synthetic oils I can find for my L28's.

    I drive L28's every day and rack up thousands of miles a year without any issues. Heck, one of my L28's has 400,000 miles on the original cam/rockers and is still going strong on "store brand" 10W30.

     

    The question really is how may high power custom muscle engine builds and how many rebuilt old MG engines also have problems during the "break-in" period while running high "anti-wear" additives?

     

    well, given the nature of my first comment in this thread, I suppose I will field this. I haven't made any posts because most of the details of the matter have dimmed in my memory, but as I recall the blame for the camshaft lobe destruction was about equal parts lack of zinc, and poor metallurgy in aftermarket camshaft blanks.

     

    The steel in many aftermarket camshafts (and, presumably any new rocker arm surfaces) now available for flat-tappet engines is not up to the task of long life under intense spring pressures without the zinc additive.

     

    A factory camshaft blank, factory rocker arms, and ZDDP additives are three steps you can take to avoid this catastrophic problem that anecdotal evidence suggests is possible. You are the one who has to read the information available, and analyze the anecdotal data available to you, and make the call on what goes in your crankcase. For the record, I haven't driven my Datsun in five years, (oh my god i cant believe its been that long) and when I did I never used anything but inexpensive brand name Dino oils. (Whatever decent brand was on sale.. Typically GTX or Pennzoil, but I'm not picky.)

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