mtnickel

I'd try the traditional approach of using a pullup resistor first. Pat seems to think it worked fine on stock tachs. If that fails, I'm sure I could throw one together for you. If you need specific notes on what the "pullup resistor" method is, I can outline it.

Here's another member who had some to say on the capabilities of the stock pump. http://forums.hybridz.org/topic/76319-bosch-910-fuel-pump/?p=726454 "33 gallons per hour at 38psig and 12.85v" with stock pump"..."which is enough for about 270rwhp" That 270whp is likely very very optimistic. Note: 1) You'd probably want a reasonable safety margin for slight voltage dips, temperature fluctuations, etc. So figure 10% less. = ~245whp. 2) If you're on stock wiring, your pump may not see 12.85. Could be much lower. Lower voltages can drastically affect the flow rate of the pump 3) that measure above is at a static 38psig. Figuring you will run at least 10psi of boost, the pump will need to run at more like 48-50psig. (Remember the Fuel pressure regulator references the manifold pressure). The higher pressure the pump has to work at, again, the less it will flow. Add all that up, and I would probably only feel safe running 200whp. But given it's age it's a tossup. Back to the short answer "it would run, but I wouldn't suggest it" (I assume pat meant "wouldn't" above). Good luck with the build and welcome to the RB Z world!

The stock tach has at least 8k ohms of input impedance. Extremely unlikely I damaged the ECU regardless of whether there was 12v or ground reference signal inside the circuit. Here's more people who experienced same signal type for reference: "the RB20 tacho uses a 0-5V square wave signal. The ECU only appears to switch pin 7 between open and ground, so i'm assuming the tacho provides it's own 5V connection to pin 7 through some internal electrics." "yep, that is exactly what I found. The ECU appears to just invert the #1 coil signal with a low side driver." http://forums.nicoclub.com/info-on-using-stock-tach-t132119.html A pullup resistor, yes, should always solve issues with aftermarket tachs not working. Aftermarket tachs typically accept the 0-12v signal easily. I can't explain why a simple pull-up resistor worked for your stock tach and not mine. I can assure you I've read of many people who can't get the stock tach to work however. Perhaps the Rb26 and Rb20 ecu are different? Perhaps your stock tach was in better condition? Maybe the 12v square wave you send is on the cusp of triggering and the hitachi module is finicky of how strong a signal it gets. What I can state with certainty, is that emulating the signal that the tach originally received (the coil negative type) is likely your best possible chance at getting the stock tach to work. Sure try the simple pullup resistor first, but if that doesn't work and your Z's tach was working before, then I'd give a circuit like this a chance.

As a side note: I happened to have a spare 260z tach I was testing with and when I couldn't get the adapter to work initally i was going to just build my own tach driver just like Jim. the white and black wires in the tach are just the leads of a current meter, and that meter is the tach needle. it registers more or less linearly to 6000rpm with 21mA of current though it. For full sweep, it is probably roughly a 0-25mA current meter. Keep that in mind if your one shot multivibrate hitachi unit fails and you want build your own tach circuit. There are many designs around the internet on how to do so, but keep that final current value in mind for your design. Mark

Hey guys, So I tried to read around for a definitive word about how to get the stock tach to work with the RB25, but came up a little empty. Some have said this: 1) It will work if you use a simple pullup resistor http://forums.hybridz.org/topic/109455-rb20det-utilizing-stock-gauges/?p=1023058 http://forums.hybridz.org/topic/69786-tach-issue-after-swap/?p=674261 2) It will work with an MSD tach adapter 3) It won't work no matter what. Well I tried the pullup resistor and had no luck. As a little background, the stock tach triggers off the coil negative signal. The coil negative signal actually looks like this: reference (and a good read): https://linnbenton.edu/auto/scope/ignite/pri.html Before point 'a' the coil will show 12v (because the other side of the coil is always supplied with 12v). Then when either the distributor points meet (or electronic ignition triggers) it gets shorted to ground. For how long it sits on ground is the dwell time (the time time current is allowed to build in the coil). It's when the coil negitive is released that you get a massive spike to B. This can often be hundreds of volts. It's due to a property of coil's (or inductors) where current in them wants to continue flowing and when it doesn't voltage rises (very short explanation). Once the spark completes the voltage settles to 12v again. It's from this graph that we learn why the options may not work. The stock tach does not trigger of the rising or falling edge of 12v, it actually triggers when the large spike is measured. Jim from zdriver took it apart and found this: "It consists of some protection circuitry and an RC network to differentiate the pulse from the (-) terminal of the ignition coil." reference: http://www.zdriver.com/forums/240z-260z-280z-performance-technical-124/74-260z-tach-grounding-problem-17555/#post328041 So now we know we need to give the tach the same pulse type signal. The megasquirt guys I believe came up with the gist of the idea: Here, the ECU (MS PCB) gives a signal to a transistor (2N5551) to flow switch current through a relay coil to simulate that voltage spike. Although it says relay coil, it could be any appropriate inductor coil, relay coils just happen to be readily available. So great, now we all we need to do is make a similar circuit using the nissan's tach output signal. I actually built the above circuit, but it did not fire the tach. Most places I read stated the nissan's output signal was a 5v Square wave. If this was true, the 5v through the 1k resistor should be enough to turn on the transistor. I didn't have a scope to measure it myself, but the readings on the multimeter made me second guess if it was really a square wave. After doing a bit more internet research I've found that the ECU itself likely just switches between an open circuit and ground. Those who measure a square wave may do so when the ecu is connected to the tach which possibly has a built in pullup resistor. So now I simply added a pullup resistor directly to the output of the ecu and ran the same circuit, and voila working Tach! circuit looked like this: Design thoughts (for beginner circuit designers like myself). Some of the resistor values may change depending on what transistor you use. You want the transistor to operate in a saturated state. To do this the following must be true: HFE > IC / IB The transistor has a spec called HFE. This is current gain. Try to find approximately what the current gain is under the load we’ll have. Our load is the 14v supply through the automotive relay. My relay was about 80 ohms, so the current into the collector (IC) was roughly 180mA. On the spec sheet, it showed a minimum current gain of 120 at 200mA. Using this HFE­ of 120, it’s a formula that Ic/IB be > 120. Since Ic = 180mA, IB= 1.5mA. We also want a safety margin so perhaps make the base current even higher. One site suggested 30% more which would yield about 2mA. I had originally built the circuit assuming the 5v signal so this value was close, but upon switching to 12v, it was higher, but only 5mA, so lots of extra turn on current. I have read some cheaper NPN transistors can have much lower HFE gains, so take note to adjust accordingly With 2mA of current into the base: V = IR. 14V = .002 * R. R = 7000ohms. So R1 and R2 need to add to less than 7000 ohms. I'd say make sure each is at least around 1k, but I just happened to have these 2 values handy so used them as shown. 680 is about as low as you’d want to go for the pullup resistor; 1) to limit current running through the ECU, 2) it’s at about ¼ watt limit of the readily available tiny resistors. Finally, my 260z had a 2.2k tach resistor in the passenger foot well. Now i'm guessing the stock coil put out a much higher voltage considering the current going through the stock coil, so it was likely added to tame that voltage down slightly. We dont' want to do that since our relay coil probably isn't firing voltages quite as high, so bypass this resistor out, or simply remove it and connect the new tach signal to the other side. Lastly, a std 12v relay makes a great template for buidling the circuit. it has all the terminals you will need (4 - 12v, ground, tach in, tach out), it has the relay coil, and they often have a built in diode you can repurpose to protect the ecu output. Though this isn't mine, mine is very similar. I will try and get actual pics up later. Anyways, this is getting very very long, but I wanted to get it out there before I lost my enthusiasm of the great victory of getting it to work. All to often i move on and forget to share in my success. Regards, Mark

To add to this thread. Just an FYI, but the more you grind from the red portion (second lobe notch), the more you will have to compress the door to close. Yes, the geometery will be better and the lobe will be able to rotate properly instead of binding, but you now require the door to press in that much further to allow that latch to reach it's latched position. Moreover there is a higher tendancy for the door to have rattles when shut since there is more play. The best solution is probably the rubber piece. This allows the cam to rotate more and provide a better angle for the next tooth/notch. I however don't trust myself with being able to glue a tiny piece of rubber to a cam that is covered with grease/oils/years of grime. I opted instead to just add material to the blue area. I built up an extra 2-3mm on the initial face (blue edge) with a welder. This worked great allowing the cam to catch sooner and get the second cam into the right position (basically I am adding weld material to the striker face the equivalent width of whatever the rubber piece would be. Also to note, I now have the freedom to drop the striker plate down to get better door alignment. Beforehand, if you dropped the striker at all you make the angles even worse and it would not shut at all. No problems now. Pics to come.

A few issues: 1) Clutch Slave cylinder: I went with the 85 corolla/celica one listed on a few sites as a possible retro-fit. Was only like $12 on my rock-auto order, so I gave it a go. The modifications of drilling out the holes weren't too complicated, and it did leave quite a bit of meat on the forward face of the tabs (where the force is applied). It is however a 13/16" slave, not a 3/4" like is stock. It's actually the same size as the nismo rb25 slave, but know that you will get less pedal effort, but also less throw. As such, it didn't fully engage the clutch how I had the stock pedal setup. I needed to back off the pedal stock and adjust the free play to be quite small both putting the pedal height and freeplay way out of stock spec for the Z. This allowed the clutch to fully engage but with a high pedal position. Might be useful for those with other clutch systems where more force is needed, but less through (perhaps twin disk? I'm unsure if their finger system is different, but throwing it out there). Alternatives are the 2005 maxima slave, but I don't like this solution as it puts the bleed screw not at the top of the slave which could leave air in the system. 90-97 accord slave is other option (cheap <$14). It requires holes to be drilled as well, but is the correct bore. Also heard it's rod is likely too short and may need a new one made, or extend the stock one. I'll probably just get OEM though as they are now available for around $40 from a few vendors (compared to the $120+ I had seen when I was looking a while ago). Engine starts and runs like a champ. Very smooth with no knocking, ticking, or anything. Quite pleased. Exhaust Fab all done: Downpipe: It was sprayed with zinc weld-thru primer, mostly to protect the raw welds, but decided to do the whole pipe while i was at it. Since it is designed for the heat of welding, I'm hoping it'll deter some rust/corrosion from happening. Wideband bung put in as well as far away from the outlet as I could manage comfortably. Though it is not seen in the photo, on the backside is a welded bracket that attaches to the bell housing to reduce stress on turbo and exhaust manifold. Next was a flex pipe for additional flex protection. Free tip: Weld the v-band flanges either bolted tight together (with clamp and spare flange), or preferably clamped to a large piece of aluminum. I welded mine a little fast without alternating around the joint and with minimal cooling and I warped them a little bit. Luckily they have a male/female notch and still seal well with a small bead of high temp rtv. Pic was during mock-up stage. Tip #2. Tack more than you think you might need. while removing the pieces a joint may have tweaked just a bit and caused me to have to cut and re-weld at a spot to have it fit like I wanted. Carrying back to resonator: I utilized what I believe is a stock z32 trans mount which had hangers ready to be used. That goes into a vibrant Ultra-quiet 3" resonator. Sits about 3/8" away from the driveshaft. I figure if anything, the system will sag and give more clearance. Then to another v-band that allows muffler to be easily removed...then 2 90's to get to my 3" magnaflow (12229 - 14" body, center in, offset out,5x8 oval): Here it sits in the stock opening. Muffler is mounted vertically: All welded:

Nevermind. I looked up the part number and saw it is spec'd for the z32. Upon looking up the Z32 FSM, i found it should read: 70-90ohms @ 60*C (140*F) 21-24ohms @ 100*C (212*F). So it appears my sensor is probably incorrect. Slight chance I have foam/air in my cooling system that is causing it not to read full temp as well. Posted spec for those interested. Stock 260z gauge reads roughly 130-140* at the 80 ohms I measured, so the z32 sensor seems correct.

Does anyone have the resistance values for the stock gauge and for this sensor? I got my rb25 running the other day and used what i believe is the sensor listed above (except from Beck Arnley). It was measuring about 1.5k cold and about 80 ohms at operating temperature. However, the gauge does not read 180-190 deg (like my tuning software and thermostat indicate). It was showing only just over the base 120 (perhaps 130ish). It's an early 260z. So curious if the earlier 240z gauges had a different resistance scale for the coolant gauge, or whether I got a dud sensor. If anyone running the nissan sensor listed could let me know the resistance at operating temperature, it would be appreciated.

While the paint may have some insulating qualities, for my application it will hardly be a factor. I don't plan to track the car at all really. Perhaps an auto-x session here or there, but the heat buildup from a 60 second run would be pretty minimal. Also, I was cautious not to put the coatings on too thick. It was pretty rough looking beforehand with corrosion and whatnot, but now looks quite nice. And really the main factor will be the insulating properties of the paint. Yes, if it was a thick ceramic paint, then it might insulate exceptionally well and cause temperatures to skyrocket. But it was just a primer and thin light silver paint. If I painted a piece of sheet metal on one side and heated the metal side with a heat gun, yes, the metal side would be hotter than the painted side, but the painted side would still certainly get hot and radiate heat as well. Perhaps not as well, but I'd think it would act as just creating a temperature differential. Say of 20-30* or something. So it's not as if differential temperatures will skyrocket under abuse from the "insulator" but more than it will just reach a slightly higher temperature. Maybe I'm wrong. If I am, on the upside I didn't use heat paint, so if it really does get quite hot, it'll just flake the paint off Mark

Diff Pics: Japanese Xebec Helical. While it's not usually mentioned, shimming is important to both make sure the carrier bearing preload is correct as well as make sure the backlash does not change. Perhaps why it's not mentioned however is that the diffs are usually built to fairly tight tolerances? It measured within .001 on backlash as stock. Preload was perhaps a bit tighter (tough to tell on my inch-pound torque wrench), but I attribute that likely to the new bearings which weren't set in yet. Also, I've read that these diffs could have stood for a touch more carrier preload anyways (stops the diff from rocking while under heavy loads). Wirewheeled the whole lot: Primed alum cover. Engine enamel for case: Silver paint, and then ultra-grey RTV and she's ready to go:

-Mount ECU to firewall - throttle cable install (picked up a mid 90's sentra cable...likely need to mod the pedal end a bit and epoxy some studs into the firewall. See Throttle cable thread: http://forums.hybridz.org/topic/83248-rb-throttle-cable-bracket/?p=1124235 -rewire Fuel pump. Had a HORRIBLE 2+V drop with stock wiring (12.2V at battery, 9.7 at pump = SLOW). I had anticipated a little bit of a drop and would appreciate it as a way to quiet the walbro 255 with my lower power requirements, but that was just too much. Done. Had 1 extra circuit left on my nifty tercel terminal. - Have fan shroud made for taurus fan on ae86 rad. - Finish up intercooler and intake pipes. Done- see end of this post. - diff install - Diff painted, LSD installed. cover on. ready to go. - fab exhaust - ground wire harness (need a big bloody crimp) - All Done. Engine bay electrical completely done. Intercooler and Charge pipes: Buddy of mine finished up with welding my custom end tanks on. They feed right through the stock bulkhead fairly nicely. The 90* wall inside isn't ideal, but it shouldn't be too much of a pressure drop at the HP level's i'll run. Mount's welded on the bottom corner. Had to also weld a little corner piece into the body. IT's isolated with a bolt and rubber/silicone. If you look close here, you can see the 3/4" inlet tube welded on the bottom. This is for the IACV. BOV installed. Custom Reciric tube made from the stock one. Note the fake Apexi filter. I'll likely swap it in for a real one when i have the money. Dont' buy these. The maf bolt holes don't line up and I had to fill, then drill/tap 2. After some reading on maf turbulence, I read that it shouldn't really be this short. Most OEM cars with MAF will typically have 16"+ of intake tubing, plus they often have 2 moderate bends. While it may not seem logical, the turbo blades can cause turbulence. I'm not sure the details, but I believe it's due to the speed at which the wheel can turn creating eddy's as well as small pressure backups when letting off the throttle. While the BOV should relieve pressure, it isn't a perfect system and having a buffer in between is ideal. Regarding the BOV, or as it should be called recirculation bypass valve, it's good to have the return pointing directly back to the compressor at a gradual angle. I went with what DSM used to do and just had the tube inside the intake and close to the turbo inlet: The bend of the internal pipe is smooth, but the hole was cut quite oblong in the 3" pipe to allow it to sit high. That divider plate is actually there to reduce the turbulence from the turbo blades. Its also there to support the honeycomb grid which will do the same. This will go down in the pipe. Don't worry, I have one of those going into the maf as well to create a laminar/steady flow into the maf. I'm not too concerned about any restrictions as it still should have an effective diameter much bigger than the turbo inlet (49mm). Coolant Overflow: Instead of buying some fancy billet unit, I just hopped over to the pick'n'pull and grabed a 1997 1990-1993 honda accord resevoir. Came with a bracket as well that has just 2 10mm head bolts. Ran it through the dishwasher a few times and mounted up in a nice spot... Fuel pressure guage visible below. Ground wire all done: Opted also to paint the from air dam area with rocker guard...sorta like truck bedliner: Fender Seal: As a cheap alternative to the oem, I used a piece of black vinyl commercial baseboard for the upper frame to fender splash seal. Few weeks previous I had this little milestone: Anti-climactic open turbo exhaust first start. Didn't run too long since trans didn't have any fluid. Up next: - Fab exhaust. Fab custom heat shields/header wrap. - reinstall bumpers/fenders/spoiler/cowl/etc - get wideband gauge mounted...not sure where yet. Either single A-pillar pod, or on the steering column - custom fibreglass radiator shroud - install diff and all shafts/etc.

Another tiny update: Put Shifter noise/dust/etc cover on. I used the entire RB25 cover and bracket. Had to form the bracket a little to fit tunnel profile. Also had to screw in a piece of sheet metal to cover remaining gap. I also put some RTV on the bottom of the rubber in areas where it may not have had ample tension from the bracket. Got gauges all sorted out. 280z voltmeter (couldn't find a 76' to match the 74' font, but oh well). Autometer boost gauge. A note on the 280z gauge. Awesomely enough, I didn't even have to swap plugs. The plug pattern and clip system is the same even though they look different. I deleted the shunt resistor and repurposed the white/red wire for the 'lamp' charge light. It's not that involved. But it will help to know that the 2 black wires in the 3-pin plug are for the voltage meter. One of them has a red band (which is positive). While it may not be readily apparent from the shot above, I actually mounted the gauge in the same plane as the other gauges. I've seen others just slide it in, but it looks out of place when it's 1.5" further forward. I also wanted to keep the angled stock plastic for a uniform look. I used a the amp gauge as a donor. The black metal piece shown below has a built in angle to have the gauge sit further back, but also straight. It was carefully trimed until the lip on the gauge fit inside it: Here's an angle where you can see the width of that black angled piece: A few dabs of hot glue to secure the gauge to that ring. Then replace the plastic lens after a thorough cleaning, slide it all together and a few more blobs of hot glue to hold it together. then just cut out the back of rear case to fit over the gauge. It actually comes to a depth that almost keeps it pinched together. I simply wedged in a piece of hard foam to keep tension. The only other issue was then to mount this. Since the illumination light is in the middle, the stock strap couldn't be used. However, there are a few extra slots and I used one slightly offset to the driverside. Then it ended up pressing nicely against the gauges mounting posts. Also, shifting the gauges over isn't too much of a chore, simply cut a few bands of the electrical tape on the harness and move the electrical connectors over one space. Sorry for rambling about the gauge, but I'm thrilled with the result. It also comes with a green filter to go over the bulb. The illumination had a terrible hot spot at the top, so I used some black RTV strategically on the bulb to even it out as much as possible. Shifter Mod: In stock location, the shifter seemed much too far to the passenger side. I cut a wedge in the bottom of the shifter shaft, but it over about 1.5" and welded it back up. Though the shifter is now slightly angled, it's much preferable to being too far away. Picked up custom driveshaft. I had a Z32 yoke as the RB one wasn't available. Upon chatting with the driveline shop, they said there is 1 replacement joint for the Z32, but typically it's a non-serviceable part. No Circlips to disassemble it, so it needs to be pressed. They said by the time they clean up the yoke and replace joints, and balance, would be about $200. $350 for a brand new shaft instead with new slip yoke and diff flange and high quality spicer joints. Plus 12% tax here in BC, but seemed like a great deal. Pats Driveline in Surrey. Getting closer! What's left: -Mount ECU to firewall - throttle cable install (picked up a mid 90's sentra cable...likely need to mod the pedal end a bit and epoxy some studs into the firewall. -rewire Fuel pump. Had a HORRIBLE 2+V drop with stock wiring (12.2V at battery, 9.7 at pump = SLOW). I had anticipated a little bit of a drop and would appreciate it as a way to quiet the walbro 255 with my lower power requirements, but that was just too much. - Have fan shroud made for taurus fan on ae86 rad. - Finish up intercooler and intake pipes. - diff install - fab exhaust - ground wire harness (need a big bloody crimp)

My setup for those curious: Junkyard Sentra (1995-1999) cable. I heard DOHC 240sx are also good, but I wanted to make sure I had enough length and this one surely did. Bracket at throttle body fairly simple (just some 1/8" bent correctly and notched to accept cable): This shows the length of the cable. It actually loops around first for less strain. If the cable was shorter, it would either have to cross the valve cover, or there would be a fairly aggressive turn right off the firewall. Having the cable this long was actually ideal in my opinion. I will zip-tie and/or create a cable-hold for it latter to secure it under the intake manifold. The nissan had 2 studs inside the passenger area that held the backside bracket. Here's the bracket on the opposite end: Though hard to see, there is actually 2 holes in the lowest portion of that metal bracket. Also, there is a rubber seal as well on that entire face. That bracket got trimmed down to fit in the stock location. That included cutting of those long bits and cutting fairly close around the trapezoidal (diamond) shaped bit. Then it was a matter of securing studs in the firewall. I couldn't weld as my bay was painted, and I didn't want a through bolt, so i opted to first tap the drilled hole, and then used some JB weld to secure (so I wont' need 2 people to install/remove). The first hole I drilled was slightly off center and as such the rubber seal was very close to not overlapping, so being OCD I redrilled the hole. The extra glob of epoxy certainly isn't attractive, but I prefer function over cosmetics. A little touchup will help. Next was securing the cable to the pedal. If you look at the picture 2 up, all that was required was a 10mm hole with a slit to allow the cable. This allowed that white clip looking thing to clip into it. 1) cut piece of 1/8" metal to receive the cable 2) grind pedal shaft to accept weld 3) attach metal bracket to cable 4) pull all slack out of cable. This required angling the bracket back maybe 20-30 degrees from normal. as such the cable connection point was about 3" further back than stock. This is due to the free play in the cable compared to the sentra mounting points. I've seen others simply cut off the cable at the right length and weld a blob on the end, but repositioning the end was simple enough. 5) Once happy with the angles of the cable as well as the slack, I tacked the bracket to the pedal. Here it is once removed: Finally, reinforce the bracket with an extra piece, and cut off the stock tail so it looks better. paint it black, install and enjoy. Feel is great. Note to make sure you leave the throttle body end of the adjustment in the middle so you can adjust it so that it is just just fully open when your pedal hits the pedal stop. Also, if you're wondering if there are any variances in the length of the pedal throw vs what the RB25 throttle body requires, there isn't any. The bracket on the pedal mounted roughly exactly where the stock end attached to vertically (giving same length of throw).

Anyone have a grenaded diff or a set of these kicking around? I was assembling my ring gear to my new centre carrier trying to meticulously follow the FSM, but forgot that the FSM I had was for the 12mm RIng gear bolts :S. Thus when I was stepping up my torque and got to about 90 ft pounds, things got a little soft and then a head snapped off. UGGGH. Got out the stub though before the red loctite grabed though at least. Anyways hoping someone has these from a parts diff and wouldn't mind parting. I know there is a set of 8 available for like $12, but then I'd have to order 2 sets and courtesy nissan I remember is pretty steep on any sort of shipping.

Do you have a diagram of the boost controller you built? My Initial reaction is that perhaps you built a ball/spring type boost controller but failed to put in a relief hole on the waste gate side. Here's what I mean: Notice the line in the middle "1/16" bleeder hole". Did you happen to make sure you put this into your boost controller? If not, then what can happen is that you build boost (say when you go WOT), then once the boost pushes the ball and gets to the wastegate the boost starts to drop. The issue is that once that ball closes again you have pressure stuck between the ball and your waste gate permanently holding it open = no boost. Check that, and if you don't have a relief, drill a 1/16" hole somewhere on the waste gate side of the lines.

If you don't want all the fab of the S13 conversion, just google Ground Control 280zx. Looks like front and rear will set you back about $400 or so. Then just get shocks of your choice.

My guess... his foot for the first 30 seconds, likely idles after that. Probably doesn't drive it when its below 40-50* which would further reduce the need for warm-up aux air. And lastly, being a performance build, perhaps idles slightly higher to compensate. The AAC and idle valve or mostly niceties for easy drivability even when very cold and the smoothest idle possible.

There are many threads on spring rates. I think you are lacking any replies for a few reasons: 1) You have not stated which vehicle you even have 2) You have not indicated what your intended purpose for the car is. Do you want an aggressive street car? A track only car? 3) Generics..."formula 1 bread koni's"??? which koni's? what model? front or rear of a 78? etc etc. While 200 lbs seems like a lot, remember the dry curb weight is 2825 lbs. Add in 100lbs of fuel, 200 lb driver and it could be easily 1500lbs over the front wheels. 200lbs on 1500 is only a 13% increase. difference of maybe 200lb/in springs vs 225lb/in, ie, not that significant. The biggest factor will be the purpose of the car combined with how much comfort you want. One thing is for certain and that is it would be recommended to get coiloveres so you can get the ride height you desire. Anyways, I've chirped in enough. I suggest you state exactly what you're trying to acheive and why your research has left you with doubt.

My first post was before the video, not fair. haha. Anyways, it certainly sounds like rod knock, but that wouldn't necessarily explain the loss of nearly 3L of oil (i believe stock holds about 6L). The RB should be a very fast spooling engine with the tiny turbo it has on. I still suspect perhaps the turbo was blown...then it leaked out tonnes of oil...then the oil was low which led to oil starvation and killed a bearing. Just a guess. That's really too bad to hear that your (apparently) newish engine may need new bearings. Good luck with getting figured out and working better! Mark

"My first guess would be blown turbo and then losing a ton of oil out either the intake or exhaust seals. That in turn might cause the rattling sound of the turbo clanking from terrible bearings. Does it spool well and have good power? Black smoke when idling? on the gas? etc. need to know more to help. What have you checked so far." Edit: above was written before the video was posted...i'm not incompetent.

What are you power goals? I'd sell both and do an L28et. I bought a 260z 4 years ago that had no engine and decided to go RB, but had I known how much of a hassle it was going to be, I would have gone L28et instead. Simple electronics, strong, can reach 300whp without too much trouble, no mounts required. etc. Perhaps I'm jaded because I had to do fuel, intercooler, new rad, electronics on top of all the other troubles of the RB swap (mounts, ECU, new driveshaft, oil pan). But having something that was simpler and still could put out good power would have done me well.

Well hello all, It's been a little while since my last update, but the end of spring and summer have been busy: a few weddings here and there, time off, wife keeps planning weekend gatherings :S...no time for the Z. But alas, I've made some headway and am excited to likely be able to fire it up within the next month or so. Fuel System: Fabricated a sump/baffle for the EFI pickup. Didnt' really want to go through all the hassle of a surge tank/lift pump, nor did I want to have anything sticking out the bottom. This was my next best idea. In hindsight, I would have made it shorter (minimize fuel heat soak through pump), and made the inlet more tappered and possibly on the side to allow for better fuel entry into it. It should work just fine however. Next was to replace all the vent lines. Got pretty good rates just at rock auto. Go into the universal parts area and select fuel line. They even had 5/8's and 3/4" fuel rated stuff for less than $2.50/ft I believe. Sorry no pictures, but perhaps for next update...here they all are: Now, I was getting rid of the Vapour/charcoal canister, so that leaves 1 line not connecting to anything on the vapour tank. It attached to this device. What is, is a 3 way valve. Found it on a 94-00 integra. The line going to the tank allows for vacuum to enter freely, but at the same time it is a check valve for gasses exiting. Now, it's called a 3 way because it has a built in low pressure spring to bleed off excess pressure in the tank. More than a few PSI can cause your tank to bloat and throw off fuel pressure, so if it expands, it bleeds off (this time to atmosphere, though you could vent it to the pre-turbo inlet area if you were an environmental nut (wouldn't help when not running however). Here it is mounted with my external walbro 255 and pre-pump filter: The filter there is a wix 33972. 5/16" in and out and had the biggest and coarsest filter element i could find (50 micron, and roughly 2" in diameter). Also installed an inline fuel gauge near main filter in engine bay. Thanks about it for fuel. Next I finally got the engine bay fully painted. I tried color matching the datsun grey in a single stage urethane, but it never came out right. Instead I used samples and picked a base clear that was pretty close. Turned out to be a lexus color which has a nice exteremly fine metallic (almost enamel flat like). Here's just the base: and the entire bay: Once that was done I could start on the LARGE job of wiring: Custom injector harness to pair up to injector resistor box (using low-impedance GTR 444cc injectors). Stripped stock harness: Figured out which wires to keep and remove. (a generic writeup at Hybridz) Those not used: Getting there: Notice the retrofitted relay box and injector resistor. Also found a cool tercel battery terminal that has 3 built in fuses. Worked a treat and allowed me to bolt up the RB's stock connector ring (for starter and alt). I then grew tired of taking wiring pictures. But know that It is also nicely tidyed up. - Ran coolant fan wires (and took activation signal of z32 ecu) - converted to relay driven headlight system (through that box above). - replaced old ignition switch - re-used 2 s30 circuits at fusebox to run RB gear (I believe interlock 1 and 2 fuses...one wasn't even connected to anything I think because I have canadian car). - mounted battery tray with bolting system (so I can clean under there if need be in future. Also ported my 18g turbo turbine: Turbine is T3 GM style. there is a 2.5" 3 bolt to V-band adapter on it. Up next, mount the turbo and oil lines, finish fabricating charge lines. Plumb bypass valve, plumb vacuum lines, run boost gauge line, install voltmeter, fabricate downpipe, finish ground wire harness, and then FIRE IT UP! Dropping the driveshaft off today as well.

Post 7 Sorry to bump from the dead, but does anyone have any definitive info on getting the 280z 3-wire tach to work with the rb's logic signal. I've read some have simply used a pullup resistor and had it work, and others couldn't get it to work no matter how they fiddled with it. I've also read some modify the tach by removing a resistor and that helps it to work with things like an MSD unit. Just so many sources floating around it'd be nice to have a final word. With so many claiming no success, I may attempt to build a negative coil emulator (with a coil/inductor). I likely intend to build the same circuit as in post 7, as it seems the most likely chance of success (gives you that 30v+ spike that perhaps the stock tach needs). Here's a good read for those wondering why the tach might not work...explains the coil (-) signal and the signal that the ECU gives... http://www.toymods.org.au/forums/tech-conversions/6355-tacho-tech.html And a detailed writeup on building one: http://www.toymods.org.au/forums/tech-conversions/22574-how-tacho-booster.html other NPN transistors will work as well, so dont' get hung-up on that if you intend to try this out. Any thoughts appreciated.

I had very minimal rust restoration experience starting my Z, but I can certainly say i'd agree with the above. Unless you have a great passion for metal work and the space and time. I bought my 74 Z for roughly $2000cdn and it needed the typical areas (pans, doglegs, battery area/firewall, etc). The more I dug into it, the more I figured I should have stripped the shell and done had it blasted, but I dont' have the means or time or space to do such a thing. If I was to do it all over again, I would troll the desert area craigslists (phoenix, palm springs, nevada, etc) and spend 5-10k on a much much better starting subject. Sure its a lot of money, but you gotta factor all your time and parts in. But all the power to you in whatever you decide!