stupid_fast

A couple updates here. On Rayapp2's 81 slicktop turbo, I was able to decode and map out the 1981 turbo ECUs, those definitions are now available. The big thing here is he swapped to 60lb injectors and I successfully recoded the stock ECU for correct fueling. Found the new K value and rescaled the TP load scales and its happy. That car has further running issues that need to be solved, including the o2 swinging way more than my car does during closed loop, but the coding did its part. During this process I found a couple issues with what I was doing before, the rom chips I was using, ect. On my car I found the limits of fueling reliability on the stock AFM, which is about 200whp using virtual dyno to measure so probably inaccurate, but it should be within 10% of a real number. The boost on my car is back down to stock until I finalize a solution to make the fueling reliable. Moates has gone out of business, so my ostrich emulator is now unsupported and all the documentation is gone which is annoying. I was able to get Tunerpro working with emulation without offsetting the files, so everything gets a little easier there. Exactly how far can we go with this system? I have an idea, but its a couple months away from being fully tested. Edited 5/11 With the new lower latency W27C512 45z roms and some cheaper open source rom adapters I've eliminated a lot of bugs I used to have. With my innovate unit logging MAP RPM & o2, I can use MegaLogViewer to show some meaningful data. Actual O2 readings vs load, with a good Air Flow Meter I'm hitting close to the AFR table targets. Keep in mind MLV is displaying load as KPA from a map sensor, the load scale in the ECU is theoretical pulse width. Also here I'm battling boost drop with my intercooler and exhaust setup, so this is probably less than factory power output, but still demonstrates the efi working properly in these conditions.

J-pipe is fine its just non-intercooled so its more prone to detonation due to the higher intake temps. You should be able to run quite a bit of power as long as the timing is conservative and you keep it a bit rich. The NA ECU has no ignition control, the advance curve is mechanical like a carbureted car. I'm pretty sure there have been NA-T guys on hybridz who have run a stock dizzy without problems, you should be able to find some old topics about it. For the knock sensing its pretty simple, you can even use a mechanics stethoscope with a pipe bolted to the block, or an electric setup with a small headphone amp and a generic knock sensor. The factory sensor should probably work too but I haven't listened to it. This is what mine looks like with a generic headphone amp off amazon.

For drivability you really want good amount of advance in the low load areas. I never really understood why anyone would remove vacuum advance, since with the correct weights setup it runs the same at the top end anyway. The stock map has a lot of advance. remember however it had 7.4:1 compression, motors with flat tops and NA motors will take a lot less ignition timing reliably especially with the stock j-pipe. I just built some knock ears and I'm still getting light knock at around 5200rpm with only 24 degrees timing at a 12:1 AFR on the j-pipe and stock wastegate. My motor is around 7.9:1 compression. I was probably saved before by the motor running very rich mid 10:1's on boost. These motors hit mbt around 20 degrees at 3000rpm (at 6psi), and they're prone to knock in the 4400-4800 range. Really the take away from this is just make sure you have some kind of audible knock detection when you start rolling into the boost for the first time, there's no real replacement for a good ECU with proper spark control. I was collecting some more information before doing a final update and conclusion for this thread, which is most likely going to end with my car running on a dropbear ECU. It was fun to go in and verify or debunk rumors on how things worked inside the factory ECUs.

I think the suspension is just too stiff, I'm going to get softer springs first then see from there. There's practically zero body roll in corners and not much compliance over curbs. Also running the big MSA sway bar kit front and rear, the rear bar might be too stiff. Unfortunately I threw away my stock sway bars. The tires are 225 front and a 245 rear, they've got most of their tread and are about 2 years old but garage kept. The rears are also a few months newer than the front tires. If they were shot I would expect another few seconds on the lap time. Grip level is about right for a 340 treadwear summer tire and I didn't get a chance to dial in the pressures, they were about 28psi hot. camber -3 front -1.8 rear toe 1/16" in front 0 rear About 3.5 degrees of castor. It used to have heavy understeer bias when it was lower a few years ago when I ran it at Thunderhill west with 205 tires. Almost the same alignment specs from back then, just different ride height.

I did lots of things to the car this year, but didn't feel it was necessary to update here until I had some results. The main outstanding issue with the car after Thunderhill was the cooling system. Got a TIG welder earlier this year in February and learned how to booger weld aluminum enough to start on cooling modifications. I started with building an intercooler setup. Since I'm staying with stock EFI, I wanted to add a recirculating BPV so that required the intake boot to be replaced. The factory intake box does not fit with the intercooler, considering my options I was unhappy about just running a pod filter in front of the radiator. After a bit of angle grinder action, I found room for the intake under the headlight bucket. I bent up a piece of aluminum to box in the filter. Took one out of the lemons build guide and secured it with self tappers. Rivet nuts can be added later. Welded up the internal water pump bypass. Welded up the radiator cap, removed the restrictive shroud, and relocated the oil cooler behind the radiator. Methodology here is that the cooling stack is supposed to run from coolest to hottest. Added in a cheap ebay expansion tank and overflow bottle with a 22psi cap. I extended the fuel pump bracket to add a pre filter and upgraded to an 044 pump and changed the differential to an open unit. Built another set of axles, and tired of killing them I raised the rear ride height by 1". Also adjusted the camber back to negative since I'm not drifting. I modified the wilwood combination prop valve bracket to fit on the z32 bmc. Changed the cam to a factory 'A' cam. The extra RPM wasn't doing anything for me. I decided it was time to rebuild the rear brake calipers even though they were not leaking. After pulling them apart I found the cylinders were complete junk full of rust pitting. Got a set of reman calipers and now the rear brakes are working well again. Built a bracket for a generic ebay adjustable wastegate actuator. It seems to work better than the old worn factory units I have. The ZX engine bay looking even more crowded than it did from the factory, however its now at the best state its been in since I got it. Back to Buttonwillow for the yearly SpeedSF black Friday event. Last years event they lost the lap timing for my fastest lap, but it was somewhere in the 2:13 range. I had some issues in the morning but was able to get out for the last two sessions and managed to get down to a 2:08.582 with the same tires from last year. Positives from this event, the car is making a lot more consistent power in spite of running rich. Still on low boost around 8psi. The cooling issues are completely gone, the water temp stabilized at 185-190 and didn't move pushing it for a full 20 minute session. Oil temp stabilized at 250. Now that the car is running faster the oil pressure is dropping on almost every right hand corner. A baffled oil pan is next on the list before I can get back on track. I changed to an open M30 differential, but raising the ride height gave a huge oversteer bias on the car and now the thing is really skidding around everywhere. Going to move to softer springs and adjust the suspension geometry a bit. Going to be interesting from this point on, I feel like the car is at a stable baseline and I can start actually tuning things rather than fixing major issues.

@AlShelby I will not be parting out the T5, but the points dizzy is available. @Villeman Sorry I gave away my extra thermostat housings already, I can't find any more.

Hey guys, sorry I haven't been on here in a while. @chopkins12 I have the clutch still, your profile says you're in NY.. its going to be unreasonably expensive to ship it. I don't have any spare turbo parts other than what's listed. @McKleenZ message me if you're still interested in dropping by. @ISPKI Shipping is very expensive for any bulky parts, you're probably better off getting it local but I can get a quote if you're determined.

@260det, thanks for that. I've got a few ideas going right now, going to do some prototyping and hopefully make some improvements. A few updates from recent activity. Earlier last year when I rebuilt the gearbox I replaced the factory transmission mount isolator with the 240sx unit. The only modification required was drilling two holes in the crossmember. This Megan racing mount came on one of the 240sx boxes I got, and is a bit more robust than a ZX unit. The engine mounts tore again, so I ordered some OEM Nissan mounts from japan. The OEM mounts immediately delaminated on installation, so I ordered up some silver project mounts and they work just fine on the stock ZX. They are a bit stiff at idle with the cam, but while driving I can't tell the difference. Took the opportunity while everything was apart to finally fit on my #5 bypass, should help flow at the back of the head at least a little bit. AN to BSP fitting was easy enough to source. The throttle body heater cap was also leaking, so it was a good time to re-seal that. The front sway bar was also binding due to some janky drifting stuff I did to get more clearance for the brake calipers at full lock. Steering is much more complaint now, as it should be. Went to Thunderhill East this weekend and got on track for my first lap, engine was misfiring and I get black flagged for oil smoke in only a few laps. The driveshaft munched up the transmission output shaft seal, and it sprayed fluid all over the exhaust causing the smoke. I suspect it was due to the old failed engine mounts, but I'll find out for sure if it fails again. The parts shop in town had the required seal, I also got a coil and spark plugs to combat the misfire. I missed a few sessions, but I got it back on track with no leaks and running better than it has in a while. Set a 2:16.030, at least at a similar pace as the rest of the run group. The water temps get too hot after just 4 laps flat out, as mentioned previously in the thread I'll have to start doing something about this. A while ago I had adjusted the water temp enrichment table in the ECU to go very rich when the CHTS detects 240 degrees, and it worked great. At just about 230 on the gauge and it goes rich so I'm not tempted to keep pushing it.

260DET, thanks for the comment. I'm still running a locked center, and really can't justify the expense to upgrading to an LSD for this car since I'm not doing any level of competition. A huge contributor to the high speed instability is the alignment settings, my last alignment was optimized for drifting and was almost ideal for that purpose. An LSD has been on the list for a long time, but with how beat up this chassis has gotten over the years I'm starting to only do the maintenance required to get as much seat time as possible rather than upgrades. I'd like to also start messing with some front air dam and basic budget aero as experience to apply to my lemons team car. Nothing crazy like a big wing, probably just front air dam, under body panels, and a simple diffuser to keep the end back down. Cooling is still an issue, typically Its creeping up to 220* water temps after a hot lap session. I'm currently working on a few more maintenance bits and optimizations, going to be on thunderhill 3 mile in a couple weeks with SpeedSF.

I lost a bunch of pictures from recent work when my phone died, but here's a brief update. When I slapped in my cam in a few months ago before the Buttonwillow event I also installed a new Powerbond crank damper PN# PB1212N. Last weekend I went to check the timing after my dizzy cap screw backed out and couldn't find the crank mark. Pulled everything apart and re-checked the balancer against a degree wheel, the outer ring has rotated by about 35 degrees. I bought the new part because I was afraid of the 40 year old factory unit slipping! During disassembly I found that my new aftermarket engine mounts are also starting to fail again. Going to just order up some OEM nissan units, the original factory parts never had issues. Annoying to still struggle with reliability at this point, but at least there's less things to fix at this point. After ignition issues at Buttonwillow I realized I simply hadn't changed my dizzy cap & rotor for several years! Finally took the time to finally install these Accel 8.8 plug wires that have been sitting on the shelf for over a year. Really can't tell if they've helped anything, but they look good. As it sits today, waiting for the decision on what crank balancer to go with. From Buttonwillow a few months ago.

Hey there, I already got some spares to test from another Hybridz member and confirmed mine were still OK. Thanks though!

Having trouble uploading the video, but if it worked here's a lap from my recent visit to buttonwillow. Had some running issues, but overall felt great to get out on track. edit; re uploaded w/ youtube. Fasted lap was 2:21.374. https://youtu.be/xv4rmxQ1vH8

After taking a closer look at the part, it seems i made a mistake with the mustache bar. Its in fact an R180 mustache bar. Sorry about that!

Parts located in Sacramento Delta area, California a few miles off hwy 12. Reasonable offers accepted. I no longer have the desire to horde z parts due to other goals, I would prefer these parts be used again by those who need them and not get scrapped. There are also random ZX parts I still need to sort through, all the chassis controller boxes for an 83 such as the dash diagnostic control unit and cruise control unit. L28e dish pistons with rods $40 L series 6 cylinder points distributor $20 L28 F54, bored out too far, needs to be sleeved. have sonic test numbers. $80 obo 280zx turbo oil cooler core $40 L series 'white bunny' clutch setup, 240mm flywheel. $40 280ZX turbo R200 long nose 3.54 with welded center $80 R200 long nose 3.9 with welded center $80 good shape 1982 turbo ZX T5 box, needs reassembly and some parts, message for details. Will not part out. MANIFOLDS: 2x L28e EFI intake manifolds $75 each 2x L28e EFI exhaust manifolds $75 each 1x L28 smog exhaust manifold welded up $75 L16 exhaust manifold 1972(?) $50 WHEELS PAIR of 15x7 +22 Road line 4x114.3 no tires $100 PAIR of 16x8 +20 XXR 4x114.3/4x100 with new Archilles ATR 2 225/50r16 tires $200

Other than a bit of a mishap installing the rear main seal, Gollum's new loaner motor ready to go. I dropped it off earlier today. Came out of a 240z in running condition that my buddies doing a v8 swap on. Had a pair of SU's and a points dizzy on it! To my surprise it was a P90/F54. Put front & rear seals and replaced the valve stem seals, installed an A cam and a newer OSK timing sprocket from my engine while I was at it. Looks like a clean original turbo motor, but there is evidence the timing chain has been changed at some point. Should be a good runner for Gollum to get some seat time while he collects parts for his swap.