My NB unit (not sure of its source, but the integrated one, probably NB2/NB8B as that is all we got here with ABS) was wired through the handbrake as an 'off' switch, my understanding is that was factory for ADM, USDM may be different of course. Both units I used were sourced locally from the secondhand market, but whether they originated in ADM cars or from 'japanese import' JDM is unknown, and I do recall that I had a handbrake warning light on the racecar dash specifically so that I could see that the ABS was 'switched off' (the ABS light being a warning of system malfunction, not on/off as such although when that light illuminated the system was off.)

Of course, I hadn't thought that through regarding wheelspin, though with no pressure in the lines it may not matter if the unit activates on wheelspin, given the pulsing releases pressure. So, it appears that handbrake (light) on = ABS off, and brake pedal light on = ABS on. That implies two brake inputs to the ABS unit, I will see if I can dig out my circuit diagrams and ascertain if mine was indeed wired as per factory, or someone did something fancy with the wiring.

 

I'm looking at the pinout right now (attached). There's 18 utilized pins, 8 are for the wheel speed sensors, 2 are ground, 3 are 12v inputs, 2 go to the datalink connector (K-line and TBS), 1 is the brake pedal 12v input, 1 is the ABS indicator ground output, and 1 is the E-brake/brake indicator/low fluid ground input. In my experience wiring mk60 ABS units, you can just leave this alone. It may disable ABS if the E-brake is up or brake fluid is low, but that's not a problem if you don't wire it at all. I'll disable ABS if needed by turning off the wake-up power which appears to go to pin Z.

 

Hey, so I just spent a solid hour and went through this whole thread again. It's really crazy to see how much power this car made with that IHI turbo and upgraded wheel. Now that this is all fresh on my mind, I gotta know - what failed? Another turbo failure? Or engine failure?

 

Thanks Curly, it looks like a little repurposing/customising happened, but it was a racecar so that is de rigeur!

 

Picture dump: Still plugging away here. Had a few hours today to work on it, started by fixing the vent line that was drilled through by our office guy, better than fuel, return, or brake line I suppose. Slipped a piece of -4 push-loc hose over it and clamped it on, barely pictured below. Impressed by my new phone's macro mode though.



Got an undertray on, rear NB ladder brace, and you can see some plates in the back as the start of our rear bumper bar. Waiting on some 1.5x.094 DOM to finish that up. Hoosiers are pretty ragged at this point, they were on our shop Honda Fit after an entire race weekend on Greta (
https://www.miataturbo.net/build-thr...-racing-84775/) so they're just our rollers for now.



It's all NB header/midpipe/muffler, the cat and resonator are gutted, we had a mid pipe with both removed, but it fit like ****, so we'll run this for now. Definitely some weight to save with this setup, but that's for another day. Ladder brace is mounted pretty low in the front, I may end up cutting the front cross bar off.



Quarter panel is finally finished, sanded, and primered. We've got a gallon of NA classic red that's supposed to be sprayed on weekend of 3/29-3/30, but we're also planning on our first test outing with the orange Merc GT3 in the background on Saturday, so we'll see.



Had a hardtop without a window, but this one, again borrowed from Greta, wrapped black with a window, so we'll run this one for now. Gonna be really sad to see some of the OG stickers leave. The trunk had holes from 3-4 previous wing setups on it, so we bolted a mariner trunk on. Not sure if I mentioned that yet. It'll be a aero-less setup for now, we'll see how the balance is and go from there.



Interior is all painted and buttoned up, just small bits left like radio box. Lots of spare plugs tucked away behind the tombstone on the Motec harness, shock pots? Wheel speeds? Traction control? We'll see. We now have NB2 ABS knuckles front/rear, and an entire ABS system, but we'll see if we mount that or a mk60 e5 system from a modern BMW. Well, 10 year old BMW at this point, but modern to me.





Engine bays just about finished, last fab project here is the intake box. I had a K&N panel filter from a NA sitting in a parts bin, and our fab guy John took that as a challenge and started making an aluminum intake box with quarter turn hardware, beautiful welds, and some ducting to the fender area where Laz used to have intercooler piping. It'll have a 3/8npt bung for an AIT sensor, and a hose barb for the exhaust side of the valve cover. PCV side will just have a filter on the giant competition catch can, if that doesn't catch anything, we'll probably eliminate that for weight and simplicity for later races.



Aerocatch pins are in, just need to do the actual hard work and install them in the hood.

 

Overheating on WOT. Replaced the Fab9 intercooler with a piece of pipe and overheating problems disappeared. So it needed a radiator, ducting, maybe a better intercooler, we knew the turbo was over stressed, which would require a manifold/turbo/downpipe/exhaust(?), wasn't as easy back then as clicking "buy now" on a Kraken setup, so Martin took the opportunity to part it out. Ironically he put his time/money/effort into Greta, an N/A enduro car. That got Ecotec swapped, eventually turbo'd, raced in Trans Am, and we're currently looking at a 8hp swap. With all the complications of that setup, when the opportunity came up to enduro race a BP powered NA, we jumped on it, and hence the rebirth of Laz.

 

Made it to a test day at the Ridge, in Shelton Washington. Car preformed great, first session out I did a 2:03, made some tweaks, mainly looked over the car to give myself confidence that it wasn't about to catch fire, and 2nd session did a 2:00.7. Martin (OP, greddygalant) did a few laps about matching my time with a 2:00.9, but reported some low oil pressures. I saw the same in my sessions, but did an oil change to get off the thin break in oil after my first session, and although it went up a bit, his and mine back-to-back sessions proved it wasn't a fix. Packed it up after that before we scattered the engine. Engine felt and sounded great, we'll verify with another sensor at the shop, then tear it apart.




Tested with our customer's AMG GT3, we had a low trans pressure warning at our last outing with it, found out the previous owners had left the spring out that goes behind the filter, so we re-installed a new one, and brought it with us to test. Rough life. Definitely some wealth gap in the paddock with Laz sitting next to it.




Even saw Moti's old NB for the first time in the flesh, never had a chance to go say hi, dunno who the new owner is or how well he did, but the car still looked great!



Paint and probably an engine swap are next on the list, along with replacing the booster which I think got a leak during all our fab work. Pedal was pretty stiff and difficult to modulate.

 

aww so curious to see how creampuff did

What do you think is causing the low oil pressure?

 

Appears to be a dying sensor. Never seen one die other than just reading zero, but this sensor was kicking around my tool box for a while, is a brand I've never used before, and was hard mounted. Screwed in a new AEM SS sensor and it's reading 70+psi when cold, 60ish when hot. I'll take it. May mount it to a short -3 brake line to isolate it from some vibrations. You can just barely see it beneath the VVT hard line.

Last few things it needs is ducting, maybe an oil cooler, HD eccentrics from SM (gave ours to a co-worker, and now they're out of stock, curses!), and a lower temp thermostat in the reroute. Need to chat with @turbofan about the 180* part number. Oops, looks like they list it on their site. Motorad/Stant 45848. Could go back and not tag him, but too late now.

Did some back/to back intake testing too. Pictured is the intake our fabricator threw together, uses a stock panel filter. Zipties will be replaced with little 1/4 turn screws once the right length arrives. Draws air from the old intercooler hole.

Blue line is just throttle body, red is with intake connected. Worth about 5-6hp and ft/lbs from 3000rpm+.

 

The air box looks great, but the odd placement of the top weld seam location is triggering me as an engineer who designs sheetmetal parts for a living.

 

I see that I have been tagged, though I am not needed.

Nice results from the intake!

 

Did you get to drive the GT3 or were you just pit crewing for the customer? I drove one of those in my sim racing league for a couple seasons. It took me a second to get used to the front-mid layout, but once I got familiar, the car rotated like a dream.

No idea how similar that would be to the real thing.

 

it was thrown together with scraps, over the course of ~6 weeks, mainly just spending 5-10 minutes on in before work. Weld is a bit weird, but I’ll take it. The joke is that’s the first corner we’re going to wreck anyways. That and/or the freshly repaired quarter panel.

 

You're pulling oil pressure data from the VVT actuator area on the valve cover? How much change in pressure do you see from VVT actuation? I have an NA6 oil pressure sender and gauge in my NB2, and it shows some pretty massive swings in pressure based on throttle position with the stock ECU. Unplug the VVT and it's back to "normal" with only RPM and oil temp affecting the pressure reading.

Did you have to notch the NA hood to clear the NB2 shock tower brace? I wouldn't have expected to see that extra weight on a racecar.

Looks like you've got a great car on your hands.

 

Lol no, not that good yet. I'm relegated to the BMWs, fastest car I've driven can do a 1:45 around the ridge, the AMG could never get heat into it's tires with all the track day traffic and was still doing 1:35s.

Hood might require notching on a pristine NA for the NB shock tower, but Laz is not that. Might have minor contact but I'm not worried about it. On my own NA, it barely rubs the paint off. Weight is marginal, as are benefits, but we had it, so I figured why not.

I only see what I would describe as "noise" in the oil pressure signal when it activates initially. During it's sweep, oil pressure continues to steadily rise with RPM. Definitely no massive swings. There's a BSPT galley plug I remove, tap the housing to NPT, and install the sensor there. Where are you getting pressure?

 

I just removed the oil pressure switch on the VVT oil line near the feed out of the side of the block, and replaced it with the bulkier oil pressure sender. On the NB1 you need an adapter to space it away from the knock sensor, but the VVT line moves it enough that I don't recall having to use any sort of spacer. Maybe the pressure dips are just a quirk of my particular engine and sensor. It's got the startup valve clatter from oil draining out of the VVT mechanism, and we had to open up the VVT actuator/sprocket at some point. Maybe it's using more oil than it should to get to the right VVT angle. I don't fully trust a 35 year old sender and gauge anyways, and it's been fine for the past 60,000 miles.

 

FYI on oil pressure sensor block/extenders. No brass. With the vibration of the B series, those things can snap off if cantilevered out too much. We have seen structural failures here. Keep everything as short and steel is possible.

 

Yup we use 1/8npt to -3 steel adapters with a length of -3 brake line in between, all sourced from our local hydraulic store. Never seen a failure from them. The brass **** seems to come in all the gauge kits, which I don’t really use. If I do, it goes straight in the garbage.

 

Well hell. I'm going to order and replace my brass adapter stat! It's been fine for a couple of years but no need to risk a failure.

Laz is making good power. In for seeing some videos though. That GT3 is a beauty and one of my favorite cars.

Regarding oil pressure dips, I see a small dip when VVT activates initially but it recovers back to normal quickly. My pressure sender is connected where the stock one was in the NB2 engine, and I use a BSPT to M10x1 adapter (Bosch temp/pressure sensor).

 

Bought a gallon of "classic red". It's an amazing 10 footer paint job, perfect for slapping a bunch of stickers on. Only piece left is the bumper, fender and trunk are already painted, just not bolted on. 2 weeks and counting until our race.