TrumpetRhapsody

I haven't done a test run yet, but I'm 99% sure I found the cause of my knock "issue". When I made my custom timing indicator I didn't have a good way to verify TDC, so I just eyeballed it based on the cam marks and never circled back. I bought a proper piston stop, and lo and behold I was set at 11* over-advanced . That'll do it.

Updates! I found that I was still using the opto-isolator tach input/output circuit with EDIS, as originally suggested by B&G. MSExtra now recommends using the VR circuit, so I swapped to that. I haven't noticed a huge difference, but the placebo effect has me thinking it's running a bit smoother. I'm still having trouble fully eliminating my light ping above 10psi, even with timing pulled back to 15* and running 11.9 afr. I'm worried about EGTs (which I'm not monitoring) if I pull any more timing. I'm starting to wish I'd spent the time on some headwork before reassembling the longblock. Maybe I'll look into installing my methanol kit until I'm ready to take the plunge into E85, but I hate to have to do that temporarily. I just don't know what else I can troubleshoot. I do have a pretty constant miss at idle that I haven't been able to track down, but I can't see how that would have anything to do with my ping.

Right now it's just sitting in there, since I removed the forward console mounting bracket for weight reduction lol. Eventually I plan to put that back in and solid mount the cage to it.

Here's the Amazon link: https://www.amazon.com/dp/B0CP3D46NH There are various options in 1-din, but all from China. I think I still had to trim my console a bit to fit a 1-din cage.

Looks like I missed some updates! In September I showed my car in a local event, TougeCon. They had a nighttime parking garage meet that I installed underglow for, and a daytime "car show" at the town square. Was the first time really getting the car out, and it garnered a lot of attention! I still haven't dug into diagnose whether I still have the noise issues (probably, I still see some spikes on CLT and AFR), but as mentioned in this thread I did finally resolve my jumpy tach. Turns out using a 12V zener was allowing noise through, and using the proper 18V zener cleaned up up. It's nice to finally have a solid tach. I picked up a cheap Chinese touchscreen head unit that runs android, so I could load ShadowDash and connect Bluetooth to Megasquirt for logging and some extra gauges. It's pretty slick! I have it auto-uploading logs to Google Drive when I hit Wi-Fi, and can download and burn tunes. In the last couple weeks I noticed a distinct whine after the engine got up to temp. It sounded like it was coming from the block area on the passenger side. Eventually I realized that back when I did the L28ET swap in 2009, I blocked off the inlet/outlet on the factory oil cooler since I didn't have a filter stud handy. It must have been bypassing oil the entire time I've run this engine. 🤦‍♂️ For now I got a stud from Nissan, and have an oil cooler coming from GRW. After the tail light swap, I realized the late-style license plate light wouldn't fit the early panels. I took inspiration from Skillard, and fabbed up a simple blanking plate using LEDs. I also pulled the trigger on a fuel system refurb. I'll be retrofitting an Aeromotive Stealth 340 into my factory tank, using a Radium stainless 10 micron filter, and upgrading to PTFE lines to eventually run E85. No more fuel slosh and starvation! In the meantime, now that the engine is broken in I've been working on dialing in my tune under boost. I set up some knock ears using a knock sensor, portable audio amplifier, and some headphones, and it seems to work pretty well! Once I hit around 10psi in any gear, I can clearly hear some ping. I'm holding steady at < 12:1 afr, and have backed my timing out to 19*, but still haven't gotten it to go away completely. I'm going to drastically pull timing and richen things up to work from the other direction, but that's already less timing than I'd expect necessary.

Just wanted to update this thread to say that the 12V zener is not a good idea, as was suggested here: https://www.msextra.com/forums/viewtopic.php?t=39695 Over time I started having a jumpy tach under load, and I think it was somehow also contributing to some ECU noise. Switching to the correct 18V zener cleaned up both issues.

Found a few more issues: The EDIS module had an intermittent ground on pin 9, and working backward I found a cruddy solder joint where I was experimenting with a diode. My PIP/SAW shield was grounded at MS and combined with the VR shield at EDIS pin 7, creating a ground loop. My PIP/SAW shield was combined to another ground where I connected the MS harness to the EDIS harness, ground loop #4. With all of that cleaned up I still had RPM spikes. I enabled Noise Filtering and that seems to have fixed it, but I'm not really happy with masking a noise issue. I'll try to scope the VR and PIP signals at some point, and see about adding a condenser to the coil + just in case.

After much deliberation, I decided to go with FutoFab's HD wheel stubs, 930 CV axles, and diff stubs. It took me a few days during the week to install the wheel stubs and bearings, and I finished up the axle install today. It's nice to have a fully refreshed and strong rear end, though I'll need to dig back into my diff at some point. I'm getting some noise at speed and on decel, and despite the CVs being smoother I still have a slight on/off clunk.

Dove in deeper than I thought I'd need to while addressing the RPM spikes: Replaced my EDIS crank sensor, which was chewed into at the tip after contacting the old trigger wheel. Modified the mount to close the gap between the crank sensor and new trigger wheel. Discovered that I combined my ECU ground, ECU pin 7 sensor ground ref, sensor ground wires, and LC-1 grounds all to a chassis ground at the firewall with a ground strap to the battery. This goes against prevailing wisdom to keep sensor grounds separate and direct to ECU pin 7, and to keep the noisy LC-1 heater ground far away from the ECU ground. Realized the ECU box is mounted to metal (chassis ground). Potential ground loop, so likely not ideal. Unfortunately, despite significantly reduced noise in my logs and no more resets, I'm still getting RPM spikes under load/boost. I'll have to dig deeper.

Got my RCAs and inner/outer tie rods installed, though unfortunately T3 neglected to include the bumpsteer spacers so I'll have to circle back and dial that in once those arrive. Drilling out the steering knuckles was HORRIBLE. Due to the metal hardness it took me 30+ min of drilling per side, a broken $20 drill bit, and a considerable amount of strength/pressure. If anyone else installs these I highly recommend pulling them off the car and using a drill press rather than drilling by hand.

Went on a 100mi twisty cruise last weekend, and discovered some new items to address. Tires are rubbing the front flares in turns Someone (me?) re-drilled a rear nutsert after breaking a bolt off in it, which has now failed One air dam bolt disappeared Getting some RPM spikes above 3k rpm Logging is dropping out, not sure if it's a loose serial cable or actual resets Bumpsteer is terrible I've re-drilled the front flares to give more clearance, drilled out and replaced the failed nutsert, replaced the air dam bolt, reconfigured my reset bluetooth adapter to get wireless logging back, and bought RCAs and T3 bumpsteer adjustable tie rod ends. I also swapped out my faulty ignition switch that was giving me trouble for the initial start.

At long last I can post a few reveal pics, now that the "look" is complete! Though, I do still need to drill the body to properly mount the front and back bumpers. The paint is TH1 Midnight Blue Pearl from the R32, ceramic tint for heat rejection since I'm AC-less, and partial PPF on the buckets, hood, and behind the tires.

So far so good! I have 80 miles on the rebuild, and nothing too concerning yet other than a bit of valvetrain noise I'm hoping is resolved by a hot adjustment when I hit 100 miles. Currently the car is at the tint/PPF shop, so I'll get some "complete" pictures in the next week or two after I pick it up. It's been fun getting back into MS tuning after so long, and I'm finding a LOT of areas I needed to improve. So far I've: Upgraded from MS2/E 3.3.2 to 3.4.4. Swapped from don't include to include AFR (used a spreadsheet to convert VE). Swapped from the old to new baro mode (had to retune most of my VE). Dialed back and smoothed my timing, primarily in the idle and cruise areas. Increased my tps, rpm, and CLT/MAT lag factors. I must have had the scale backward in my head originally, as they were in the 90's and barely filtering. Leaned out my idle and cruise areas significantly. Started dialing in my MAT correction, based on Gollum's findings. With all of these changes the car is running better than ever. I've always had issues with low rpm and cruise throttle transition jerkiness, no matter what I did with AE. I suspect I was way to aggressive with my timing, and had some drastic transitions causing the behavior.

Turns out this took a few months instead of a few weeks, but the engine is back in and I did the first run this past weekend! Between then and now I got the crank sensor mount modified for the new balancer, timing indicator made and marked, mounted and routed my new catch-can, flow tested my ancient 7M injectors, and verified the timing (good thing, I was 5* retarded!). It didn't immediately grenade on the first run which is a relief, but it didn't exactly go smoothly either. I pinched a brand new injector o-ring, so I'll have to go back and swap the temporary cheap rubber one I put in there. I'd forgotten that my ignition cuts the switched +12 power (powering down the ECU) if I turn it too far into the start position, so we ended up bridging the starter temporarily until I chased that down with a multimeter a few days later. Seems like I'll have to replace the electrical portion of my key switch. The EDIS firing order and orientation always throws me off so I ended up with Coil A and C wires swapped. I have them labeled now so that doesn't keep biting me. I'm hoping all the cranking and misfiring cylinders didn't adversely affect my rings seating, but we'll see after the break-in cruise this weekend. For the last week I've been working on finishing up QOL stuff like gluing in weatherstripping, finishing the 240z tail light conversion, replacing my crappy ebay steering wheel with a proper Sparco, adding a turbo blanket and downpipe wrap, and various other little cosmetic items. Full reveal soon!

Bringing this back from the dead! After my dyno session where you could see significant blow-by coming from the valve cover, the car progressively started producing blue smoke from the exhaust. I don't recall the exact timeline now, but around mid-2016 Flatblack helped me pull and disassemble the engine. We discovered two pistons with broken skirts, and one piston with broken ringlands. My head gasket was also hanging on by a thread, with very elongated bores. Since then other life priorities took precedence, and the car was basically untouched for 7 years. Mid 2023 I finally took the car in for paint, and got it back in October. Meanwhile I had the block cleaned up, found some used pistons, performed the coolant bypass mod on my P90 head, did the 240z tail light conversation, and last month finished reassembling the longblock. Sometime between 2013 and 2016 Flatblack sold his 280z, so we traded flywheel and clutch setups so I'd have more torque headroom. At some point his flywheel dowels went missing, so I'm waiting on replacements to get the engine stabbed back in and broken in over the next few weeks. Once I have everything complete, I'll post some reveal pictures of the new look! Short term I need to get a rollbar, some performance seats, and harnesses put in the car. I'll also need to get my MS2/Extra upgraded to the latest version, and apparently be a little more conservative with my tune. From there, I'll likely pursue installing the Snow Performance meth kit I've been sitting on for a decade, follow-through with the 280zx CV swap with the weld on adapters, upgrade injectors and swap to running E85, and look at swapping to a properly sized modern turbo to support my original 400whp goal.

I'm waiting on a Mustang caliper option or something. Not all of us have Wilwood-deep pockets, or need it. Looking good though! I like the new design.

Sunny: I'll dig more into that, maybe I'm thinking it's more complicated/expensive than it should be. T3 seems to think this will be a decent lower cost swap, just need to confirm that by trying it! Xnke: That is a decent Z31 axle option, but that leaves the weak stub axles. Those are the heavy hitters on price. Plus not everyone has easy access to a pick-n-pull. 240sx parts are a dime a dozen on many forums.

Meph: You still have weak stub axles just waiting to snap. This addresses multiple issues. Not saying you aren't right about not having binding issues, but there's a reason the custom center bars were made. Nigel: Nice catch on the rotor sizes. The 240sx guys were saying it was a 1.5" increase over their stock rotors. I didn't think to check if the Z31 rear rotor we use was bigger than the stock 240sx, which it is. Not much gain there, ill have to keep digging, maybe look at the cobra upgrade. I really want to avoid that drum e-brake nonsense. Trying to keep this cheap and easy.

Good to know. At least this will give me options. I'll try the Z31 bracket swap first, and if that's still not enough rear bias i'll bite the bullet and go full Z32.

Perhaps! I think I"ll be fine with 29 spline for a turbo car. I looked into the Z32 rear brake upgrade, and the whole drum thing looks like it's more trouble than it's worth. I found this: http://forums.nicoclub.com/diy-larger-rear-rotor-upgrade-t483332.html I'm thinking that should be enough to bring the bias issues people see with the SX rear disk swap back into check. Guess we'll find out!

I gotcha now, but staying 4 lug limits me to using the 29 spline axles that fit the 240sx hubs, so might as well stick with the bolt-in (shortened) 240sx axles. I like the Z32 rear brake idea though, since I wasn't thrilled about using the undersized SX units OR losing my ebrake. I'll bet I could use the SX wheel bearing and hub, and still use the backing plate, caliper, and e-brake assembly from the Z32. Please take LOTS of pics as you work on your rear brake setup. I just got all my used parts in, so I need to take apart my 240sx axles to see if I'm going to be able to get them shortened and resplined, or whether they're too thin and will need custom center bars.

I'd thought about this, since I had that diff as well for awhile. Should still work, but you might need some LCA drop brackets to get those huge diff side stubs to clear. When I was mocking that diff up trying to think of ways to make it work, they wouldn't clear. Pretty sure all Z32's are 5 lug, i'm trying to keep 4 lug. The Z32 rear calipers are a bolt on for 240sx's (which means it would work here too), but I was under the impression you would lose your e-brake? I thought the Z32 used a drum style ebrake. Can you show some pics?

Whoops, answered my own question. It does it automatically when you post the Youtube link as a URL.

I feel ridiculous asking, but is there not a feature to embed youtube videos into your post? I know for a fact it used to work on the Vbulletin site (I see threads with YouTube embedded), but so far I haven't figured out how to do it now on IPB.

Took the Z to a local dyno day this Saturday, and got 4 runs in. Since converting over to the external wastegate I hadn't spent much time tuning my boost controller to see how much of a change in dutycycle is needed to increase/decrease each psi. I started around 16psi and each run I increased it 5%. I was hovering around 18psi by the last run, right where I wanted to be. Final numbers were 315hp and 335tq, not bad! The other turbo cars there were seeing 5-10hp drops on subsequent runs, so even though i gained each run by adjusting the boost controller, I was probably losing 5-10hp in heat. On top of that starting around 5600 rpm I started going super rich, which probably killed my top end some. May or may not have given me a better peak number, but something to consider. From here I think I'll go ahead and rebuild this motor, considering I had no idea I was getting that severe amount of blowby. Also, i found a local guy that will rebuild, port/polish, AND flowbench my head for SUPER cheap. After I get all that done I'm thinking about converting over to E85 to see if it will help with the detonation issues these motors have, and allow me to run more agressive timing. I'm still shooting to break the 400hp mark without running more than 20psi of boost, so we'll see!