Daeron

That plenum looks dead sexy....

(not to sound like a dick, but) Rod length has no impact on stroke whatsoever.

That was a photo of a bearing from Josh; Greg hasn't posted us any images of his bearings yet. I am wondering what kind of motor oil was being used in the engine.. Chris (ITS owner brother #2. the eldest of the five of us) said he is pretty sure that your motor was extremely low-hours, so any sort of chemical/metallurgical distress (the whole ZDDP thing that usually comes up when someones camshaft gets chewed up) from motor oil probably would not have had time to cause an issue.. but its another datum that needs to be considered.

I think the closest thing we could get to it would be a long bar with a series of tuning forks attached to it at calibrated frequencies. In all honesty, with a tuning fork of the right frequency range and an electric guitar pickup, you ought to be able to make something.. but any low tech approach towards analysis of this problem is likely going to revolve around tuning forks in some manner.

hood, 30 pounds? Doors, 30-40 pounds apiece? hatch, another 40? thats about a passenger's weight or so. You've got the bits off of your car, you tell US what they weigh The hoods and the hatches are all likely nearly identical, but I am sure the later doors were heavier than the early ones, so you would know best what the weight difference is.

What Josh pictured is very very similar to the bearings from our uncle's U20 motor (unless my memory is REALLY failing me.) However, oiling was not an issue in our situation either; oil pressure and supply were constant and the entire oiling system was well set up and plumbed. We didn't have the money to do our BRE car ALL the justice it deserved, but the accusump and oil cooler/filter setup was done very well. The motor trashed the crank bearings nonetheless. I should be around the shop sometime in the next few days; Tim or I will get some pictures of the spun U20 bearings in question, if they are still around.

Greg: sorry, I can't help you that much myself; my brother Tim Carey was with you at Sebring though. How high in RPMS did you take it? What kind of reciprocating mass are we talking about, and how finely balanced were the piston/rod combinations? What chance is there of a fuel, spark, oiling, or cooling issue particular to these two cylinder that might've been overlooked? These guys are data fiends here, because the numbers are what tell the story. your questions might generate more and better responses with more specific information; for those of you who do not know, RevTec is an established SCCA racing team that you should simply google if you don't know who they are. This isn't Joe Q. Zcarowner asking about some random stroker build here What sort of dampener were you running, and what history have you personally got with those dampeners? Like I said, I couldn't answer you any better than Tim could, but someone around here must have had this problem before, whatever "this" problem is.

Its just, its so SMOOTH*crUNCH!* classic Awesome video man, really cool swap and now its well documented. Your videos make a lot of connections for z-builders out there, keep them coming! One thing this had me thinking... If one were to install a gearbox like this, and set the engine/trans combination back an inch or two.. do you think it would still fit and function within the stock shifter hole? Cutting the tunnel is one thing, but clearing the stock center console would be probably the more important thing in my eyes.... IF SO, I think we may have found a good spot for a cupholder to go (right in front of the shifter)

what vehicle?

Nancy boy. REAL Floridians don't break a sweat until two minutes before it starts raining at 95 degrees.

There is no if about it- I drove it ever day for five years and (estimated) over 60,000 miles. It will be again, but it wont get restored... this car will be one of those band-aid restore jobs that look pretty but have lots pf fiberglass patches and BS like that. Eventually I will scrap the chassis, but until a day when I have more money, this is MY Z.

If you have a higher res version of this photo, could you please send the highest resolution version you have to shawnmcarey at gmail dot com?? This is one of the more interesting and awesome photos of a Z i have ever seen..

Heh, not his car. I *think* that is one of Greg Ira's cars.. but Tim has gone out of town for the weekend so unless someone else who knows Ira con confirm/deny that....

Largely because (I guess) the idea seemed counter intuitive; if its old hat I'll STFU. Like I said before, I suppose its one of those things I'll just accept despite my intuition... straightener before the carb I can see, just seeems like anything afterwards would net a loss. Thanks for explaining. Well, like I said, *I* was under the impression that a gap that broad was limiting it, to say the least. Apparently it isn't as important to get as ever-loving tight as I had imagine, rather there IS an aspect of "the closer you could get, the better.." Obviously compression increases, but as it does so minutely, the squishing action of the "fluid" in the chamber is giving you more agitation and "white noise" movement to grant an octane-offset from the comp increase. One issue that I have an immense amount of trouble with is the simple fact that I don't think well in fractions of an inch; I have always preferred metric measurement and "since its Japanese anyway" I pretty well have failed to get a good sense of my conversion factors in decimal places. What sort of depth would a standard L28 dished piston have if it's volume is around 10cc? I plugged ".055inches to mm" into google and it came back at almost 1.5mm, which is about what I had thought and that STILL seems a long ways away. It just makes me wonder just how flat a set of stocker dished pistons might be grindable........

Well, in a nutshell it comes from never having seen anyone gainsay brian (1fastz) in quoting that range. I have read other numbers quoted in articles (such as the Vizard popular hotrodding article linked somewhere above) but most of those guys are using SBCs as their "example" engines, and I suppose I presumed a difference in engines may as well account for the difference in head to piston tolerance needed. Since this IS the L-6 subforum, I reached for the only/best/most common datum available to me that directly references high-quench L-6 cylinder heads. (Query: is the difference between presumption and assumption the fact that I only made an ass out of myself?) So, jmortensen, rsicard et al, what sort of piston-to-quench pad clearances would you recommend running on a p-90/e-31/welded closed chambered L head? Understand, I am asking, not goading. UR50SLO: If I spray a sprayer at a screen door that is turned to mist, and not to stream, the mist tends to group up on the screen and half of it dribbles down. That was the effect I was wondering. If theres a thousand tons of anecdotal evidence saying that screening underneath a four barrel is a good thing, so be it.. that is far from my forte, I was just asking. I am all for air straightening within the intake tract, so I was curious about the matter.

Foot firmly inserted into mouth; many thanks

I would bet that all of your problems are EFI related. this thread hereshould connect you to the EFI Bible, which is an invaluable resource. Chances are likely that your problem lies either in the TPS, the CTS, or possibly the thermotime sensor or cold start injector circuits, but it could be anything. The EFI bible CAN be used as a tool to verify, step by step, component by component, that the entire EFI/ignition system IS functioning 100% and then the problem MUST lie elsewhere. The cam timing remark meant basically, ensure that the timing chain is not advanced or retarded a tooth; the timing isn't adjustable per se but obviously if the chain is off.... Welcome to the Wonderful World of Inline Six Bliss!!! The stock EFI is kinda crummy for power, but using an inexpensive DIY EMS system like megasquirt can set you up for an easy 220+ horses NA (NA horsepower starts costing money quickly after this point.. but the car is light, so don't underestimate what fun 22 horse is capable of!) and then there is always the option of turbocharging. The stock turbo motor internals seem to be good for up to 400 horse, and for that you typically need a good big intercooler, some sort of intake manifold solution, (ITBs or aftermarket mani, stock EFI manis are largely restrictive TBH) injectors, and a turbo upgrade... but the longblock is still stock. And, of course, theres always the option to drop the stock motor and replace it with something more.... to your tastes. MY tastes happen to center around the Nissan L-series, so I'm no source of info for "all that hybrid junk" but Welcome to HybridZ!!!

Bump to show this thread to Searchy! (Rate the Thread, guys, this is one that ought to come up as soon as someone searches for it!)

Visual jet inspection and confirm that they are the same size (by measuring if at all possible.) Obvious point, but you didn't say much, so I had to make sure you checked. Its all I could think of, beyond the steam cleaning thought. What do the spark plugs look like? Dizzy Cap terminals for #4 and #5?

+12039782938745907823908723429387298374 to the 12308597293 power

(still reading the thread but) I have to point out that .033" is a VERY wide piston-to-head clearance for a quench pad... .024-.021 is what I hear is the sweet spot. Okay, the screen on a MAF is there to straighten the airflow and reduce stability..... because turbulent air moves in more directions than one, and will cool the hotwire of the MAF off more rapidly than straight laminar flow. this totally alters the signal that the MAF sends to the ECU; TonyD (I *think*) told a story about boggling his little daughters' mind by opening up his engine and "blowing out the fire" simply by blowing on the MAF element. Most of the time OEM manufacturers take great pains to place the MAF after a fairly long straight run of air piping, because many autos have experienced bucking and surgign issues that were literally wind-based due to overexposed MAF elements; its the single greatest drawback to a MAF-based system IMHO (but that is an opinion I have lately been wondering if I need more education to leave behind; I may be "wrong" but I will still say I prefer MAF based over MAP until I learn more about MAP) So, how does the screen help a carburetor?? I would have thought it would be a gathering spot for gasoline to separate out of suspension onto... I had posted something else here, but somehow it got clobbered into browser javascript gobbledygook. In short, i said I was posting largely to subscribe because I am interested in this idea and happen to have a pile o' L-6 heads so, you never know. So, don't take much offense or read any aggressive condescension into my quoting above. I caught the gobbledygook when I came back to recommend that John Coffey read the pdf file that was linked to earlier in the thread, http://www.herningg.com/singh/Engine%20Running%20Tests%20Analysis.pdf I didn't read it through in depth but it appears to be a thorough, documented analysis of this idea. I am going to look into it further after I get further caught up on my normal internet prowling; my wireless card has been out for the last two weeks.

Okayyyy, I am no LED professor here, but my understanding leads me to believe that you are crazy. IF a method for dimming the LED illumination were found, it would involve alot more complex circuitry than the simple rheostat potentiometer used to decrease the voltage to the circuit for the incandescent bulbs. I would LOVE to know if a setup that allows dimming were available, and how much it would cost.. but I am fairly certain that it would take "a setup."

My information came from a hunch that was supplemented by parts website information.. I forget which, but I *think* rockautoparts.com was where I found diameters and spline counts on the various discs. I haven't had a chance to look at any of the parts, so it is all conjecture. I would LOVE to see something come of the stuff though.

I am not even 100% positive I understand what he is saying here, but I agree with him! (disclaimer: i did understand the gist of what careless was saying)

every L-series intake manifold has the oval-shaped hole in the flange for the TB, even all of the USDM ones and we never got anything but single plate TBs. Our cars just have to cope with the awkward shaping from factory, and when people install the 60mm TB from the Ka they hog the hole out as much as possible to make it work. Snag a TB from a stanza or a 240SX or something, and adapt that on there (unless you are close to achieving your other intake setup you mentioned earlier in the thread.) If the large butterfly is 30mm in diameter and the small one is 20, then you have a combined cross sectional area of 1021mm^2. If they are 40/30, they are equal to a 50 mm TB with a total cross sectional area of 1963mm^2, and a 60mm TB has a cross sectional area of 2827 mm^2. I HIGHLY DOUBT its 40x30, but I have never laid eyes on one, so I obviously have no place to speak on that one... but you tell me. BTW, for reference purposes, a 2.5" exhaust (63.5 mm) has 3167mm^2 cross sectional area, and a 3" (76.2mm) has 4560mm^2 cross sectional area.