Tony D

Do you understand how a basic control loop functions? You usually have (R) Reset (times the controller looks at the Set Point in a given timeframe---usually per minute) This sounds like "Update Rate" in this application (P)Porportional Gain (the user-set percentage of the scale the controller will move the control valve when looking at the "offset from SP". For best and most hair-left-in-your-head methodology you need to know how they define P... Is it 1/P or is it P/1? Usually it's 1/P meaning P is the divisor, so with a bandwith of 10psi, and a setting of P=1, with an SP of say 7, and a real measured value of PA, your offset is 3, so what your controller woudl do is move 3/10 of it's travel, then look at the reset rate, and then make another adjustemnt. With PORPORTIONAL ONLY Control, you will NEVER reach your setpoint! You will ALWAYS have an offset equal to your Poprortional band below or above your setpoint. (I) Integral Gain (don't know if this is the "differential gain they speak of, but it probably is...) is another divisor setup that is equal to time. So the longer you have a setpoint offset, the more this will take into account and make an additional correction to the move size of the control valve. In the above case where you would have a porportional offset, the integral will let you close that gap to exactly setpoint in a very short order. (D) Derivative. This is a rate of change correction factor. "Derivitave" and "Devil" both start with the same letter for the same reason "Despicable", "Destruction", & "Debauchery" do, they all connotate that bad things are happening, and you best stay clear from it. Derivative can send even the most carefully tuned system into Hysterisis from even the smallest jump... Be glad it was not included (or at least I think it wasn't included)... For your best response fastest, I would use a Quick Reset Rate, initially a Large Porportional Band (move wise, not necessarily numerically!), and a somewhat medium Integral Rate. From this if you are seeing boost overshoots and undershoots on recovery, start slowing your porportional rate, till the overshoots go away. if that does not do anything, go back to your initial setting, and halve your reset rate. If it cuts it out, you will have to determine if you want a quick reset rate, or one that only makes slow porportional corrections. I prefer to keep P and I to the smallest numbers possible for finest control, and to do this a quick reset rate is usually required, ESPECIALLY when you have fast varying load conditions (like in an automotive turbocharger!)After you are satisfied with your P response, Then find a hill and see what happens when you stay in boost for a while. If it "creeps" and it's not mechanically caused then play with integral by lessengin it's correction factor. Basically in any tuning loop you first make it unstable, then make it stable. Then upset it and check for response. Tuning the control loops on Centrifugal Compressors can be rather daunting. They pay me pretty well to do it on large stationary turbocompressors. Remember if you can have the luxury of a variable reset rate, USE IT. Start fast and over responsive, and work to the stable end of the spectrum. Basically start jittery and go towards null response. I hope some of that made some sense!

There is NO turbo distributor! On a US specification ZXT, the easiest method is to simply go with MSS from the start! Of course, if you want to source a European or JDM distributor for the turbo L-6, THEN you could use it as MS alone, with the vacuum/boost cannister taking care of retard in the stock zone. Of course when you later converted to MSS, you would end up going to a fixed trigger, and negating that neato Euro Dizzy to begin with. The 81-83 Turbo Distributor is just that, it distributes the spark (on an 81 that's ALL it does! There ain't but a rotor in there!). It has absolutely nothing to do with spark production in relation to engine speed like a conventional distributor. It is a dumb box, it does nothing but shoot the sparks. It doesn't advance, it doesn't retard, and without an interface to read the pulses from an 82/83 CAS housed inside there, it won't even give you a timing pulse! Now, for a conversion of an 81 to MS alone, you most likely would simply install a convetional ZX Distributor, along with it's support, into the place where the 81 Dizzy went. It is the ONLY turbo engine in the US that will do that easily. (The 82/83 have a different spline configuration and will need to have the oil pump dropped, and the dizzy shaft rephased and reinstalled with one compatible with a distributor.) After you have a conventional distributor in there, you can use an MSD box, have it fire the coil and do whatever you like with the spark as far as retard. Advance you are limited by centrifugal in the mechanisim, along with vacuum advance canister limitations, of course. For all the hassle, simply use the tables Moby has for the spark. I have mine working again. I made a miscalculation on the number of degrees I was advanced, and had entered the wrong numbers. Under high vacuum conditions the spark was "jumping" one terminal in the firing order (at least that is what I think was happening) I have now made successful pulls in fourth up to 4500rpms (3.36 rear end) with no surging, no popping, no spark knock, nothing. Though now upon having my 81 CAS unit off the car and looking closely again, I may be able to do another mod that will not entail removal of the front pulley and rotating it for maximum advance. I had misinterpreted the timing information given in the FSM, and with a bit of work with adremel tool it MAY be possible to get just enough advance for the 81 CAS to work without pulling the pulley off, and drilling the second hole. Just for information, I will probably use my spare 81 CAS for a N/A conversion to MSS, and my spare 83 CAS/Driveshaft combo for another conversion of an N/A engine. The real advantage of standalone is being able to tailor your spark curve. Mobys timing is safe and works, you can always tune it later on. But there is really only so much you can do with fuel alone. And spark advance available in Moby's tables should add up to far better cruise and partial throttle economy than the stock system had! Can you tell I'm in a hotel room now with time on my hands? LOL

I would have to agree with Alan on the cost aspect for sure! I rue the day I made the statement "I'm not paying $3500 for any damn Z-Car with a fancy engine when I can get one just as nice from the used car lot for $2400!" Three years later, I was again taunted when the inspection rules changed and the current owner of that 432 wanted to trade me even-steven for my 73 LHD 240Z Turbo with full flares and all, along with a spare engine, and several rocket boxes full of spares. Thanks to the US Governments' forms in triplicate, and already having them filled out for shipping, I would have done that deal in a quick second! Now, it's a pipe dream unless there is some sort of insurance settlement or lotto winning! LOL The 432R models were very stout engines indeed. I would not be so quick to disparage a factory sponsored racer with well over 240+ hp in conservative tune (on carburettors) against an L24 with only 150... Lets' not even throw in the Mechanical Slide Valve Fi version seen in some places... The Z432R was a badass vehicle, engineered with no holds barred towards performance. It has been said that the specific output was over 150HP / Liter in some engines...

What did I say about "forged pistons" when we got that Megasquirt fired up? LOL

Oh, forgot to mention. The price point was not conducive for sales in the Z-Car marketplace. Originally the second generation kit was around $3400. The firstgen as closer to $2800. When they went back into production, the manifold and supercharger cost alone, retail was close to the cost of the complete analog EFI kit: $3400! So then is when Sandy decided to split the stuff up. The Holley system added another $1500, to $2000 Retail cost to the kit complete. Imagine the overwhelming response for a $5000 supercharger kit for vehicles that sell for under $1500 complete... Most people by the time it went back into production had aftermarket ECU preferences, and they were smart to realize that and offer the components.

Jim Cook Kit hasn't had a carburettor offered in the kis since the 80's! They went to the Holley Pro-Jection (or whatever the first generation four-barrel throttle body system was called, it was Analog) early in the 90's (90 I believe). Then the kit went out of production for a while, and when it came back they split the kit in to supercharger and manifold, and the injection kit, after finding no interest inthe components combined. The digital Holley system worked much better then the old system, but so many other alternatives for EFI existed aftermarket, Sandy figured it wasn't worth their effort to package it together---with all the liability of selling a "complete kit" entailed. So JCR does produce a kit that mounts the supercharger on a dedicated manifold that fits under the hood. The EFI is up to you! The Supercharger does utilize a four-barrel mating flange simply as a holdover from the early design of the kit, and the second generation of the kit using the Holley Throttle Body. Many of the successful campaigners of that kid use an 80mm T/B from a Q-Car or whatever mounted on a simple adapter plate. Simple is as simple does! LOL

There is a bit of a misonception there! The 81CAS sends 3 pulses per crankshaft revolution (120 degrees apart). The Distributor Mounted Optical unit from the 82/83's gives the SAME output, becasue it is driven halfspeed, from the drive gear in the front cover. What you have to realize is that the timing of the trigger wheel on the 81 CAS is already set for some initial advance from TDC, and is then trimmed with the physical movement of the CAS pickup within it's bracket. Depending on how much advance you want, that may or may not be a problem. Altering the trigger wheel on the 81 is a simple matter, there is a link to my cardomain page in the "megasquirt" forum in Moby's sticky. The alteration of hte 82/83 units is like twisting the distributor and has limits also due to captive bolts limiting travel, but that is easily fixed also. What are your plans for the systems? The outputs from both the CAS units are identical, even though the way they are triggered is different (81 uses Magnetic pulses shaped in the CAS unit to look like the optical's triggering!)

would that be akin to "RTV" on your head gasket, "BubbleNorm"? LOL ;^P

yep, I would try for some compressed air in the cylinders that have "0" compression and do a leakdown check. Find out where it's coming out... I wouldn't crack anything open until contacting the builder with the update and get his take on it IN WRITING. Normally two cylinders adjacent with low compression is indicative of a blown head gasket channelling between the cylinders but that third one in there makes me think of either bent valves, or a valve job so bad, the exhaust seats aren't sealing (akin to bent vavles). So I would keep from starting it until that leakdown test is performed! Good Luck!

Well, going "fuel only" is an option for those of us running distributors. To do that on an 81 wouldn't b ethat bad, since I could simply swap the distributor in, but then I would need a total rewire of my relay box for the MSS mods I incorporated into it. Anyway, this is what I did today: 1) Went out and bough some 91 Octane gas, and filled the tank to the very very very top so that "out of gas" is not an option. 2) Dropped the splash pan again, and verified the gap spacing on the CAS trigger wheel to pickup is per Nissan Specification. 3) Stuck a dial indicator on the trigger wheel and checked it for runout---thought maybe there was a wobble making the "120" trigger read the "2 Degree" signal intermittently, causing massive glitching. 4) Went back and read lots of stuff in this forum pertaining to others with problems. 5) Went back out, moved the CAS Trigger wheel to the verified bottom stop of the bracket to take out any "excessive" advance. I thought maybe the 120 degree setting was causing a problem, and using trigger angles from 60 to 120 didn't seem to make a difference.... Soooo 6) Physically measured the trigger angle to the pickup, as measured with the TDC mark I made when I did the trigger wheel mod. I got around 100 to 105 degrees. (getting close, remember that when I used 120, the timing mark was what I thought was dead on the 9 degrees it was supposed to be showing. 7) I went in, started it, it ran like sh*t, just like before. Disconnected the Alternator, still ran like sh*t.... 8) Reset the trigger angle from 120 to 90, and then checked timing--my trigger paddle was nowhere to be seen, but the TDC mark I had made was hovering around the 30 degree mark... Then went to 100, and checked timing. Then I realized the TDC mark I had made was almost dead lined up with the proper mark on the timing scale. I trimmed it 1 degree to 101, and used the timing light to null out advance, and everything zeroed. 9) Tried revving it, and it wasn't running like sh*t anymore. The ONLY thing I can figure was that when I revved it, and it transitioned from BOOST to HIGH VAC and that 40 degree advance bin was called into play, the timing on the rotor was jumping phase, causing the thing to run like SH*T, until I shut it off, and restarted it. I have the distributor in the engine according to the phasing instructions Nissan gives, and the spark is jumping off the center of the rotor tip... So if I was off say 30 degrees in my CAS timing advanced, and the advance called for 40 during the highvac bin, that would easily jump the 60 degree phasing of the distributor cap and cause problems. This is the only thing I can think of that would cause this problem. After running it for about an hour in the yard, I took it out on the road for a pull. No more spark knocking, and a hard pull with little stumbles. Had a cough around 5500 in the top of third gear, but generally pulled O.K. I successfully ran from a standing stop to 4500 in fourth gear and back to a stop in around 1/2 mile before being satisfied that it was working correctly for the day. 1 fast Z know my neighborhood, so he can gauge the pull, I was about 4500 in fourth gear at about halfway down the block short shifting the car at around 5000 to stay out of the "cough". JeffP said that was pulling pretty hard. I guess so for having a 3.36 in a 260Z 2+2... So for now it seems to be running right, and the CAS phasing on the 81 styles must be deemed critical when setting it up. No ballparking it, you will have to measure it to make sure you are dead on the timing or it will run like sh*t! We shall see how it runs tomorrow evening which will be the test on if this thing is running correctly I suppose. In the meantime, I am going to ditch the external regulated Alternator, and go with the 81 Internally regulated unit I originally had on the engine when I first started running it in 2002/2003. I didn't have "voltage creep" with it, and it seems like this combination in the car is doing it again---though disconnecting it didn't do anything yesterday, maybe it did have an effect today.... Very strange. But at least I got it to boil the Toyos, and made a run to almost the top of fourth gear that didn't have any coughs, dips, or power losses. So I am semi-enthusiastic again.

It would be illogical for me to become any sort of "opponent" since the record obviously shows success for everyone else.... but me! Far be it for me to throw stones at the MS forum, but when I went there, the help I got was FAR less than I ever got from this site! If it was not for Moby and Hybrid Z, I would have NEVER gotten past the original "WinXP" issue, or some of the other niggling issues at startup. The people on the Groups site were more interested in providing me a "guaranteed solution for all your problems that will only cost you $50" but nothing technically helpful to understand what was going on---and we all know now, that the circuit proffered to "solve all my problems" would have done NOTHING in my instance, other than to prove it was "not in the box". For $50 I doubt I would have received a refund after the installation was done! When I posted items about the possible XP incompatibility or laptop problems, it was soundly ignored. I think that is/was the most frustrating part of it all. I know we are at a deadend here, and I really don't even want to bother with the new MSEFI forum, since they were of no help during the first go-round. To paraphrase a 70's song: "Where do we go from here, now that all of our answers are dried up? And how do I get it going, knowing nobody there gives a damn?" I jumped wholeheartedly into the program, and like I said, have personally helped guys who were burning up boxes, couldn't get 'em running, or simply didn't yet have the skillset to finish the installation. And while I have SEEN it work, I can not replicate this on my own vehicle. (AAAAAAAAARGH!) I am sick and tired of using an O-Scope. It is just not making any sense, and like you said, Moby, the shaping circuit of the 81 CAS should rectify the signal to the same waveform as the later unit (and I have personally verified this on the O-Scope) so ya know, it's like "WTF, what now?" There is a place for a challenge, but this has turned into something near nightmareish porportions, and is shouldn't be this hard! I know it isn't on any of the other units I have assisted with... Hell maybe I'll reburn the code and see if that fixes it, but having to even DO that is something I should not have to do! It worked once before. But I don't think the guys on the MSEFI forum should be using phrases like "The original MSS Code is Rock Solid" becasue to me, "Rock Solid" should not require a reburn on the ECU every 20 to 30 hours of idling time. BAH! As for Bernards comment, I already have the inlet ducting from an 85 Z31 N/A, complete with the inlet silencer box, and the K&N Diamond Filter for a Z31T up front (makes for a very quiet intake tract, muahahaha!) so the componentry is already in place for the MAF... I just don't want to deal with modifying a stock harness and running all that crap through the firewall again. Though it would get me my hoodlatch hole back again (routed the MS MAP Vacuum line through there initially.... D'OH!) For the trouble, I would put Lance's system on there, since I have access to a complete system off the Bonneville Car---that's the one JeffP is lusting after! Muahahaha! Again, BAH! oh, and yeah, I forgot to say THANKS to Moby and all here who have helped thusfar. Those who got it running on this specific installation were FAR more helpful that anyone at the generic board ever was!

Nah, I saw that in "The Love Bug" movies, as I recall then it was dubbed "Jackrabbit Springs" LOL Makes you want to watch the movie to go "Oh yeeeeaaaah it IS!" LOL (My kid says "Hey dad, those hills look like the ones over by the (Moreno Malley) Mall!" Uh, yeah, son, that was where Riverside Raceway used to be, right where the mall is now! "There was a RACE TACK there? Why did they ruin it for a MALL?" We all ask that same question!)

Ill play parrot here, and squawk the same numbers: Roundtop SU's on the 260, around 22 in city driving, and anywhere from 19 to 28mpg on the freeway (depending on average speed, 19mpg was averaging almost 110mph from Oglalla to Grand Rapids on I80!) on my 240, with L28, similar, 20 city, and around 25 freeway. On a 240Z with a late five speed, and the 3.36, it was close to 30+mpg when driving steady state, and almost always above 23mpg in town. My bud with Dual DGV's never seemed to go nearly as far as I did without filling up, so his mileage was considerably less as he was "The King of E" and would go till the thing was almost on fumes, and I always was well above "E" when se stopped for fuel... Ahhh, the ribbing that occurred then... I have seen an L24 with 3.90 gears and a four speed turn in 28mpg on a trip from Phoenix to LA at 65mph steady, so multiple carburetion is not bad for fuel mileage... it's all in the tuning I suppose... I would mention that with my old blowthrough 44PHH's and a turbo system on it, I got 17mpg in combined driving, while at the track I could get as low as 5mpg! So driving style does come into play.

Beware of thinking the MT is the thing corrupting your stuff! My old laptop was the problem! When it went in to the shop for repair, I got a new motherboard, touchpad, keyboard, motherboard, COM bus..... It was randomly rewriting my stuff... Been there done that. Can't figure it out, and getting tired of trying! I could load the files again and see if that helps.... But who knows why it got corrupted. I am to the point where I don't want to have to drive around with a dedicated laptop to reload my software on the chance the system will corrupt itself again... I am starting to lean towards the "It should be more stable" camp. This is ridiculous!

UPDATED AT CURRENT BOTTOM OF THREAD Close to wrapping it up and giving in to something that I will get support with... Changed the CAS today, and that's not the problem, does the same thing as it was with the old one. Now I realize that the thing is giving a random injector pulse every three seconds after the engine dies... It's been December 2002 since I started playing with this sh*t, and I've about had it. I want to drive the car (more importantly, my WFIE wants to drive it), and helping other people get numberous cars going doesn't help my enthusiasim for the damn thing. I am pretty tolerant of snags, and working through them, but this is getting ridiculous. If I wanted to make a flying magnet trigger setup to make a standalone system work, I could have done that with a Tec 2... And at least I know it wouldn't give me these problems. I really am worried about the randomness of the failures, and really don't think that converting to the 82/83 CAS system will make that fear go away. I need something to drive cross country, and this system is not giving me that confidence factor any longer. It makes me feel like E-Baying all three of them (the fried one, and the unmolested one still on the shelf)... and using the proceeds to get a real standalone system. I really regret not taking up that one guy on the TEC2 system three months ago. At least I've personally made one of those go before... I really am sick of this B.S., and venting obviously, but DAMN WTF is going to make this thing work??? I realized today all 11 posts I have initiated have been due to MS problems I have been having. Sickening, really sickening.

"As for turning up the boost, I doubt he did that so quick as well." Ahhhh, you are a trusting soul to make that comment! When I lived in Japan, the FIRST thing I watched countless idiots do was take that HKS EVC in "Scramble Mode" and twist the knob full up, and then "see what it feels like"... Usually to the detriment of something in the engine! I might suggest a "Half Cost" replacement, he provides half the money to repair whatever is wrong. That would seem fair...

Imagine how I will feel if this CAS I'm installing today solves my problems. I was in on MS Group Buy #1 for the V2.2 Board. You do the math!

Pop Yoshimura Motorcycle Mufflers were the preferred muffler for that service while I was living in Japan, they make a nice tone. I have also seen VW Tailpipes used. I would stick with glasspacks, as you want a clean dump, and not anything with restriction. The PopY pipes were the right diameter, and usually had a nice headpipe to whack apart and hook up via an expandable flew joint....

Optical CAS 82-83 81 is, as you know, tirggered differently...

I have never bored a block before having the pistons to in hand. I don't see how anyone could do anything but a rough bore until having the pistons anyway. The final hone is done ot fit each cylinder individually. At least that is the only way I have ever done it.

may well be, but as long as the MS is powered, the 5vref should be powered.

It's and easy enough task to do one of the following: 1) Tap the them with a chaser to NPT (the threads are REALLY CLOSE) I did this on almost all of my manifold holes that did not have a Nissan fitting going back into them---it's simply easier to tap them than chase down overpriced hardware that may fit... 2) Close them up using "Lumiweld" and a MAPP Gas torch. It's like an aluminum brazing compound---it works wery well when cleaning up bumps divots, etc in manifolds.

Oh, I am not sure on ALL the preassembled units, but this one did have hardsoldered relays on the relay board, and it was the same board I have. I didn't take the guys unit apart at the MSA show, all I have is photos of my board that I used to show him that they are indeed removable! That is when he told me "mine doesn't look like that" and we decided the top coming off the relay was a "point of no return" as far as his MSS modification was concerned! LOL

SR20 CAS is driven off the cam, and has a four pin connector... Not that I have been thinking of anything for the 510... Muahahaha!