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Daeron

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Posts posted by Daeron

    Head cooling on cylinder #5 - solutions?

    in L-Series

    Posted

    detonaton hurts every motor when it happens. IMHO, my family's Z-cars have run into this issue in the past (I am diagnosing wayyyy after the fact, hence the "opinion") and we have never been anywhere near 300 horsepower, and the only turbo'd car we have owned was a bone stock 83ZXT. FWIW I don't think the turbo car ever had the issue, and I think a good deal of our issues cropped up as a side effect of inefficient cooling due to aero concerns. (The whole airdam/ductwork/seal the radiator off thing)

     

    The way I see it, this modification is an insurance policy in any L-6 that gets driven hard.

    Making my own EFI intake... The First Casting

    in Nissan L6 Forum

    Posted

    No more talk of pricing as it will suck all of the fun out! And there's a long way to go before they're running!

     

    Derek

    Hear, hear!! I would still second the idea of selling rough castings, Buyer Beware. It is just so much effort for you to put into the pieces.. I mean, if you want to make either option available (rough or finished) that keeps all doors open.

     

    It is good to be abundantly loud when emphasizing the amount of finish work involved though. :twak:

    Hybrid Z-32 power-plant options?!?!...

    in Z32 Series - 300ZX

    Posted

    Well, then, if you REALLY want to put the V8 in.....

     

    god I don;t believe I'm gonna say this, because I REALLY WANT to see the GigantorZ32..

     

    Set it up for the smallblock. You WILL build the flat plane motor eventually.

     

    You Will.

     

     

     

     

    And then its just a pick and a plant away from going into the Fair Lady.

     

    put da chebbie in.

    My 260Z project (No 56K)

    in S30 Series - 240z, 260z, 280z

    Posted

    HELL yeah!!! :rockon:

     

    Your valves are a trifle noisy, but that could be as simple as your camera being a leeeeetle bit sensitive to the normal valve noise. Just make sure you check warm clearances after a bit, especially if she seems quirky as far as needing to warm up excessively, or anything like that.

     

    Sounds great man.. Once you get these carburetors close the fine-tuning is largely a matter of economy points; not really awful to just live with until you get it figured out. When a car doesn't run right its important to have tuning tools to rule out carburetion as a problem, but if you can get them that close, from that far off... you are pretty much set.

     

     

    :2thumbs: have fun barking second, don't forget to torque your lugnuts for good luck

    Cam install/Spring height/Rocker dilemma

    in Nissan L6 Forum

    Posted

    I am going to ask something, a detail I am not 100% clear on....

     

    Were all cylinder heads originally the same height, from firing deck to valve cover mating surface?

     

    I'm not even close to sure on how to verify this guess, but after poring over the photos I am going to revise my guess to say EXTREMELY shaved N42

     

    I KNEW it... what I would do if I were in your shoes, is get a stock thickness headgasket, and get pistons that be thick enough to allow you to machine a relief in the top that mirrors that combustion chamber, and still relieve enough compression to get you down to manageable range (whatever THAT should be, by your judgment/needs/fueling ability/etc).

     

    The "mixing" you are speaking of I am fairly sure is "swirl" within the combustion chamber, and if I am not mistaken that is one of the parameters of the flame front expansion during the combustion event. You want nice, even expansion of the edge of the flame when the "kernel" pops, so to speak. This is also effected by your piston/cylinder head clearance (you need it to be VERY close to contacting those quench pads, I don't know the number off the top of my head) so spacing your head further away from the piston is problematic.

     

    Let me interrupt this explanation to clarify that these comments pertain to CLOSED CHAMBER CYLINDER HEADS ONLY, such as the P90/79, the E31, and this shaved "N42" or whatever it is. Closed chamber means, it has those flush flat spots there, around the combustion chamber which is NOT a round opening the size of the cylinder bore, as you see in later E88s, and most american stock N-series heads (the MN47 being the major american-market exception to this)

     

    Now, you want to leave a flat piston coming REALLY CLOSE to your flat quench pads, so you don't want to do TWO things:

     

    1. Don't want a 3 inch tall head gasket to decrease compression

     

    and

     

    2. Don't want to have a piston DISH that misses quenching against this pad on the cylinder head either. You want flat top pistons, AT LEAST in the region where the quench pads are in the cylinder head. (I know, the turbo engines came with pistons that had a round dish in them, stock, despite the chamber shape.. "Why did Nissan do it wrong??" you want to ask. I don't know, probably money.)

     

    So, draw an outline of your combustion chamber on the top of your flat-top piston, and start carving a relief that mimics the "relief" in the firing deck of the head that IS the combustion chamber. It can be somewhat smaller in overall "circumference" and a bit shallower; make it the volume that you need to to reduce the compression of the engine to your desired level. You are shooting for a face that is symmetrical with the face of the cylinder head.

     

    This achieves your goal without losing the "high-quench" benefit that is typically assumed to be the performance key to building and tuning a high-comp engine with a closed chamber Z head. MUCH has been said, correct and incorrect, as part of an explanation or as part of an argument, about this subject; and *I* am by NO means a sagacious engine builder of much expertise.. but I HAVE grown up around these cars, and around men who knew these cars, and have been extremely critical and curious of all that I have seen or read, in person, in a book, or via the internet.

     

    If anything I said was vaguely mis-stated, please correct me, but I am *pretty* sure I've hit this one.. am I right guys??

     

     

     

    Edit:

    Sorry to crow like a cock there at the beginning, but I was sorta proud that I was right, so don't read it as arrogance, read it as happiness. :)

    Hybrid Z-32 power-plant options?!?!...

    in Z32 Series - 300ZX

    Posted

    You sound torn, then.. do you want something to get into the car and get it to DD status with rapidity and ease, or do you want to build the car??

     

    If you want to build the car, I see no reason not to go ahead and start shoehorning the VH into it. (Or, if you MUST go domestic, whichever V8. :icon45:)

     

    If you want a good, quick way to get the car driving smoothly that is LESS complex than the VG30DETT, I would be willing to bet that you could set up a boosted (or non?) VG30E quickly and simply enough.

     

    It seems, to ME, that just about any other hyrbridZ32 is a chore, and essentially negate the possibility of remotely resembling "quick" or "easy" when it comes to the conversion. MAYBE the VQ would be along the same lines, but I would tend to think it would be MORE complex.. hence my suggestion to take a brief, short lived step backwards in time.

     

     

    Besides, it'll be good to have photos out there for posterity's sake. OMG SOHC 300ZX, WTF...

    z32 power ka24de????

    in Z32 Series - 300ZX

    Posted

    blah blah ka24de blah blah blah bandwagon blah blah

     

    bandwagon?? it is probably the single most widely available nissan engine in the US right now. At the very least, it is a valid question. The VG30DETT is a nasty complex beast to work on, and if he could pull 250+ out of a KA under the hood then by all means, it WOULD be less stressful to work on.

     

    Its like upgrading to rear disc brakes on a mild S30 street car simply for ease of changing your brake pads. Sure, I can fight the bloody drums, but I could also spend some time installing equally antiquated rear discs on there, not bothering about the proportioning valve or the big 4 piston front brakes, and simply flinging my overpriced wheel cylinders into a ditch. Advantageous? not necessarily. Desired/desirable? everyone has different thoughts on that.

     

    One of the rules here is that we LIKE the idea of fitting crap where it doesn't belong. I guess the idea of an L28 in an S13 240sx is bandwagoning, too?

    Hybrid Z-32 power-plant options?!?!...

    in Z32 Series - 300ZX

    Posted

    have you given any thought whatsoever to a VG30 No D????? The earliest IMSA cars were running strong with boosted SOHC VGs, and it is a *tad* simpler to work on. It is almost a dumb suggestion, but something about those cylinder heads appeals to me......... and besides, the "almost dumb" suggestions are sometimes the simplest ones you never thought of. If its your daily driver, a lightly boosted VG30 SOHC would suffice until you get the V8 in at least...

     

     

    Edit

    You SICK MAN!!! Flat-tops, in a Z32.... *shakes*head*

    400+ hp build questions

    in Nissan L6 Forum

    Posted

    Im shooting for over 400 wherever it lands i don't mind.As long as its over that amount.i was wondering if anyone could project if my build would make that much.

     

    The answer is that it could. No one can tell you if it would, but with the right details filling in the gaps you are on the right pathway. In other words, the total receipts will have far more itemized bits than you have on your list, and there are no guarantees.

    Is this a dash cap on my car?

    in Interior

    Posted

    I would just go buy a half-height plastic dash cap and pop it on over the original.

     

    Take the cap back off anytime you want the car to look pretty.

     

    REALLY, the only way to preserve the interior of an S30 is to park it indoors all the time, or get rear louvers and a windshield screen that you use religiously. That, plus tinted windows, make a Z SO MUCH nicer inside. Less frequent need of detailing by far. THIS is the reason camaros, Zs, and many cars with very sloped rear decks use louvers; to keep the sunlight out of the car and preserve the interior. Louvers and a windshield sunvisor (especially now that they have the reflective mylar ones; My uncle's car hasn't really been on the road for about 10 years, and HIS interior ir the one I am picturing) keep out so much UV and heat it is ridiculous.

     

    I call these cars my favorite little greenhouses.. ANY angle the sun is at, it pours into AT LEAST one of the two pieces of glass. Usually it is both. Trust me; in South Florida (as in other places I am sure) you recognize features like this in automobiles; especially when you and your family live lifetimes in them.

    Rough Idle, White Exhaust liner and Spark Plug on #3

    in Nissan L6 Forum

    Posted

    what are your compression numbers? it is easy to say "okay" but with additional evidence, sometimes a simple dip is enough to indicate a problem.

     

    I would also try swapping #3 injector with another injector, to see if the problem follows the injector or not. It is probably a red herring.. but it *is* alot less work than pulling the head.

     

    Have you tried a leakdown test? That might also help to corroborate the "headgasket" diagnosis.

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