Daeron

Cool, sounds like you are on top of things.. unless anyone else has something to say. I had to throw it out there; I couldnt remember who it was that said that recently and I didnt want to re read the whole thread to see if you had mentioned the concept already.

possibly you havent discovered the FAQ forum yet? Ultimate NA L-series thread? Read some of the stickies, I was amazed once I finally did.

1 fast z, I take it from the filename of the images that you dont really have a link you could post up for us to look at higher res versions of these images? The small pics are tantalizing, its almost not fair

and if THAT does not fix it, go to the tech tips page and read about your throttle position sensor. the engine temperature of the ecu sensor is the CTS (coolant temperature sensor) I mentioned before. Just turning the screw is almost certainly nothing more than covering up your problem, which is very very likely to be corrosion in these contacts or improper function of these sensors. Once they are confirmed to be operating properly, THEN you adjust the idle air mixture on the TB. The screw does NOTHING more than control air flow at idle, when the AFM flapper is essentially shut. Go download the EFI bible and read it through.. it explains in clear english how the entire FI system works, and it really is FANTASTICALLY simple.

Errr.. communication breakdown. I actually was trying to agree more with you, and say that to the uninitiated that turbo camshafts are even more mysterious than NA ones... I started talking about what I had been talking with my friend about... and then realized i had gone on at ridiculous length on something that wasn't *really* as on-topic as it could have been... I guess my re-write lost alot of my point. I hate being long-winded.. I guess I should have just posted the long version. The big reason I named ANY names was to thank the people who seemed obvious to point to and thank for the dissemination of the knowledge down to the rest of us.... NOT to say that any of us who may be smaller gremlins have to pretend we know nothing and trust it all to the people selling us parts. Quite the contrary, I was TRYING to say that using "Common sense" without the requisite knowledge to select the proper cam for your application is about the most dangerous thing you can do in designing an engine. Re reading my post, I really did do an abysmal job at saying what I was trying to say; my apologies.

any decent exhaust shop should be able to fit an MSA 2.5" exhaust kit onto a good header with a 2.5" outlet for not too much cash. Mario and I both opted for the "twice pipes" setup, which might make things slightly more difficult because of the way it splits the connected pipes into two right after the connection to the header. BUT one of the MSA turbo exhausts (or whatever they call the other, single pipe, single muffler one) should be readily made to accommodate a non MSA header.

anecdotal comment, I one time accidentally (i forget the circumstances, this is NOT like me) gassed my bone-stock 75 280 up to ahh.. significantly over 7000 before the valves started floating on me... I made a comment to a friend of mine tonight, who was looking at potential upgrades and mods to his '05 SRT-4 tonight. I said to him, "I don't know a great deal about camshafts, but I know how little I know, and I know I am learning more every day. One thing that I do know, is that for my purposes, almost any aftermarket cam for a turbocharged car, is considered "experimental equipment" to say the least." My point was that since turbo'd cars have only really been popular with a widespread, upgrade-minded public for about fifteen or twenty years, and that quite frankly, the REAL know-how on camshaft selection had NOT disseminated to the general public yet.. OHC engines have been around and highly developed in a backyard environment for several decades, now, and alot of people have learned alot from their friends who worked in a machine shop. As a result, we all know more of the intricacies of camshaft specs than we did say, thirty years ago. I'm talking average gearhead knowledge level is up.. but in regards to turbo motors, the VAST majority of us don't really grok what makes it tick just right. The elimination of the valve overlap, although it simplifies the number of factors to be considered, merely makes cam tuning more subtle and difficult to get matched to the engine being built. Not to talk down or negative about anyone and their choice of AFTERMARKET cam, by any means.. I initially started making the comment thinking about the remark made that the stock cam not making any power above 5500 RPM; Braap, tonyD and company are all well aware of the nuances that different specs can give to an engine's flow, but as far as us normal little people are concerned I think we have a long way to go. Thank god for the internet, and hybridZ, right???

ahh.. I am unsure of whether to even bother posting, I may be opening my mouth just to insert my foot.... ...but wouldn't putting the throttle linkage between #3 and #4 balance the load, and ensure that any potential future wear or difference between the butterflies would be more evenly distributed? I would hate to see you have any flex in your throttle shaft that might cause the #1 cylinder to be richer or leaner than your #6, you know? I mean, theoretically, I am right.. but in practice I have NO idea if you would ACTUALLY see the potential issue I mention... just thought I would bring it up, since you asked.

and then the sig, "the most successful people are the ones who are good at plan B." PRICELESS!!! Well, it wouldnt be a wise idea if you are running a P-series head, because that "unshrouding" would be defeating the high-quench design of the head, and may lead to a tendency towards predetonation. I am kinda parroting a little, here, so I hope someone comes along and backs me up, heh... but otherwise, if its actually a scenario where you would be unshrouding the valves and improving the shape of the combustion chamber, I suppose it could help.. its not just a simple question of "should I do it or not," its an issue of combustion chamber design; do you want to alter that? are you comfortable designing your own, thumbing your nose to the engineers at Nissan, and the folks at various machine shops? I don't.. (at least not until this thread develops quite a bit and we all learn something, like a quality epsiode of your favorite family sitcom. ) I'm trying to be funny, and it may be taken as offensive, so advance apologies if needed, but I am making a point, too...

P-series valves are definitely shorter than the earlier Z valves; the suppliers are not providing complete information. They tend to only post what they sell, and if they do NOT have a given part on shelf.. they don't mention it.

step one: clean the connector to your Coolant Temperature Sensor. step two: check the adjustment of your throttle position sensor. (and connector) between the two of them, they account for many many stock Z-cars presenting the "running rich" complaint. this link should help, its Blue's techtips page for the FI system. download, print, and staple to your forehead a copy of the Datsun EFI bible; it is an invaluable resource.

NO clue how accurate it is, but this page is SO comprehensive I figured it HAD to be worth something.. say the word and I will post it in one of the stickied threads. http://www.jccpiston.com/manufacturer/16758/16758.html

Thanks!

yasin, is that P90 shaved or uncut? I am trying to stock pile pictures of the combustion chambers of various heads, and I would like to know rather than guess.. thanks. Also, for posterity's sake, what kind of pistons are those? You said JE, but are they L series spec, or what?

well by using the longer connecting rods from the 240 it changes the throw of the piston... thus adding to the effective stroke. if the term "stroker" only refers to a longer stroking crankshaft, then please forgive the semantic error; In any case, as I thought the negative deck height is a killer on this one.. what pistons might I be able to use to do a mild stroke job using the stock L28 crank and the 240 rods, that would give me a relatively flush deck height?

Okay, I have been playing games with the various "calculators" for mocking up an engine build.. and I have a question. What I am thinking of revolves around the head; I am pretty set on doing the P90 shaved 0.080" for an NA motor, compression goal is around mid 10s. According to everything that I have used (and I know not to RELY on these things) if I use stock L28 crank, L24 connecting rods, and KA24 flattops, I should be at about 10:1 compression...... but I wind up getting a deck height of about -1.25-1.5mm..... The reason I am posting is to ask: is this negative deck height going to have an adverse effect on the quench pattern that I am using the P90 head for in the first place?? Also, what sort of piston options might I have to still get my mild overbore/stroker engine, yet maybe tuck the piston tops closer to the cylinder head?? Obviously, I am asking questions while sitting in the midst of a cloud of ignorance here, but I am trying to read and do my research, and I really kinda want these questions answered before I read too much more. thanks gang.

Z-ya: Do you have a thread going for your progress on this intake setup?? We had discussed it before, and I was curious.. It appears that is basically a flange from a stock intake manifold welded on to the SU manifold in place of its flange?? Could you possibly e-mail me some more photos? higher resolution would be nice, but not needed... I am just very interested in this since we had the idea at roughly the same time, and I (like yourself) have the parts laying around. I could actually potentially fabricate a few of these setups, from throttle bodies to flanges, and sell them if there were demand... so you could say that I am somewhat interested..... PM me and I will send you my email address if you have any more photos. thanks man..

hey gang, I just did a write up over on my subaru forum on installing relays for various purposes into an existing electrical system (starter solenoid control, adding fog lights, I tried to cover EVERYthing...) Since the information is FAR from make/model specific, and helps fix old cars with old wiring problems, I thought I would post a link to it here, too... Enjoy!! http://www.ultimatesubaru.org/forum/showpost.php?p=598608&postcount=1

+1 on the CTS check, a VERY common problem point... the connectors get corroded because water can sit in there. you didnt get it wet, did you?? if so check ALL FI system connectors and hit them with some WD40, try wiggling each one while youre cranking.

Blue's techtips page has a procedure to calibrate the AFM to factory spec, and that is what you want. if you really need the link i will post it.

here is the FAQ table of contents.. http://forums.hybridz.org/showthread.php?t=103836 and the Ultimate NA L-sreies Thread http://forums.hybridz.org/showthread.php?t=116680 Two good starts. Honestly (it hurts to say this) you may well dump 15 grand into an incredible NA motor, but I believe the general consensus is that you will not get much higher than 225-250 whp out of it. I want to believe differently, and alot of people do, but the numbers speak for themselves. Not trying to sway you on the turbo decision, but you do need to know the facts, and the facts seem to be that there arent many people with an NA dyno sheet that sees as high as 275. Anyone here care to prove me wrong?? I know LOTS of people have had very high pricetag motors built by rebello and sunbelt, only to be dissappointed in the power output versus cost.. Lets just say that you will certainly NOT be the first "die hard" NA guy who winds up getting convinced to turbo, should that happen. (myself would be included on that list, if i had any cash to play with)

Great story, man. We had this weird thing (i have NO idea what to call it) that we used for testing the maximum torque on the guns we rebuilt (up to 1 inch IR, snap on, and chicago pneumatics mostly..) It was basically a very large stud (1 1/2" diameter??) with a large nut on it, and a hydarulic plate on the back.. we would crank the gun up to full flow (we had a 3/4 inch air line going 30 feet from the compressor, through a dryer and oiler, and down to this station) and hit away at the thing. I have personally taken "broken" guns (anything from vanes and rotor to destroyed hammer cages or anvils or even casings) and rebuilt them new enough to achieve over 1200 ft-lbs of torque, as detected by that little device. Its just like turbocharging.. you do NOT get good power to your gun if you do not have ADEQUATE FLOW through your pipes. TonyD, when I first started reading your posts on zcar.com (years and years ago) i almost thought you were kind of an ass... THAT did not take me long to stand corrected on, and I think every day that has gone by I have grown to like you a little bit more. It is cool to find that we have some common experiences. Thanks for spending so much time here helping us pea-brained folks

I love the glasspack sound, I am SO shocked to find that so few of my fellow Z-ers opt for it.. I got one for my 75 but havent gotten it put on yet. The primary drawback (no pun intended, ar ar ar) to the idea of a "twice pipes" system is the poor scavenging caused by isolating two sets of three cylinders... but the MSA twice pipes setup has a collector pipe that attaches to the header collector, so I can't see why it would be at all disadvantageous... Mario, your videos say "full twice pipes" or something to that effect.. does this mean that you have deleted the collector and have a TRUE full twice pipe setup? I am imagining not, I think I have read the answer somewhere already, but I had to ask again. I've never much cared for the turbo muffler sound... it flattens out the highs too much for my taste. Give me some of that old fashioned BRAAAAP noise accompanied by a growl over the throaty, flat sounding turbo muffler any day. Of course, that goes out the window with an actual turbocharged engine, but for an NA car I am all for glasspacks.

there is a brake forum, this is the engine forum

Yes, you keep saying the car runs just fine with it on or off... if the car is running fine, what do you need help with? the car OBVIOUSLY will not IDLE with it connected or not. Now, the important question: ARE YOU running with the 240SX, potentiometer style throttle position sensor? I am betting $20 that you ARE. you can NOT run with that style TPS, it doesn't tell the computer anything. Unless you have a stock 280 (Z or ZX) TPS installed on your 60mm throttle body, and it is plugged in and properly calibrated, your car will NOT idle properly. The Air Flow Meter does NOT ever need to be adjusted; there is a "hack" to adjust it to somewhat richen the mixture along a specific range of RPM, but not the whole range. It is NOT worth it as a band-aid fix; it is a hack that is a bad idea, and not worth doing under ANY circumstances. If you want to fiddle with something to richen the mixture across the band, there are better places to hack into. (The CTS circuit, for example.) Far better than "hacking" anything is installing larger flow fuel injectors, but really you are getting to a point where you want standalone engine management such as megasquirt. However, if you take the potentiometer TPS that I bet is on your TB off, install one that your ECU can understand, plug it in, and calibrate it, I bet your car will idle right.