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Check your ignitor, i am/was having similar issues with faulty ignitor, had it set up wrong in ms which faulted the part. Also where in NH are you? Id love to check this out, beinig another turbo mariner.
I was thinking that the car sure feels fast for only 8psi wastegate pressure, then I noticed my boost gauge reaching 15 psi over 5,000 RPM. Apparently I need to port the wastegate a wee bit more than I already have and check what my boost cut settings are. I'll collect a log after I recalibrate/replace my O2 sensor.
Over the last week I pulled the turbo out and enlarged the wastegate hole to within 2mm (radial) of the flapper diameter. Previously, I'd just ported it and left the hole size unchanged. Now, I'm showing a pretty solid 8 psi to redline, so that's comforting (if not quite such a kick in the pants). I neglected to take pictures, because I was only getting about 60 minutes a day to work on the car.
A couple questions:
In my datalog, AFRTarget is just a flat line. This should essentially show what my AFR table is, yes? Do I need to enable EGO correction to get AFRTarget to display in the log? I'd like to be able to make manual tweaks to my VE table and tune AE some more. I was autotuning during most of the log, if that makes any difference.
How should I determine an acceptable size for recirculated BOV tubing? I have a TurboSmart Kompact dual port BOV that vents to atmosphere right now, with the recirculating port plugged. The BOV makes a lot of noise even on easy-driving shifts and that's a little more attention than I want to draw to myself. I have a 1/2" NPT port that I can install in my compressor inlet silicone elbow, but that seems rather small, given that the BOV came with a 34mm output port.
I've got second Miata in my driveway for a little while. My father is selling his NB because I made an off-hand comment that at 68 years old he'd probably be better off in an ND.
Thread resurrection. A FedEx tractor trailer stopped at my house yesterday.
What's in the box?
BeePeeSixDee?
I PayPal'd Prestige Auto on Monday and had a motor at my door by Thursday all the way from the UK. I worked with John at Prestige through email and communication was clear and complete throughout. I'm quite satisfied. The motor has a claimed 79k on it with 180psi in all four cylinders and included a complete motor with manifolds (squaretop!), ECU, wiring harness, the upper half of the steering column with ignition/key switch, and all the door/trunk/glovebox locks. One could could re-key a whole car if they wanted, but I'll likely sell all that stuff to replenish my budget.
Clutch, flywheel, and pressure plate look like they're in reasonable shape. Not too thrashed, which is a comforting sign.
There's some material removed from the crown on the flywheel bolt heads. I'm not sure what to make of that.
I haven't fully settled on my plans for the motor. I've always wanted to rebuild a motor, but if I can verify good compression, I may use it as-is with just some maintenance. Forged internals would be nice, but at the end of the day I'm most interested in better low-end than my T3 1.6 can deliver, and upgrading fueling, cooling, and driveline to handle much more than 250hp seems like a rabbit hole of cost I'm not ready to commit to. In any case, my car is running well now, so I can take my time planning and building this setup.
Yeah, I'm leaning towards at least rods. I've never rebuilt a motor before and it's something I'd like to learn.
I tried to do a compression test with my 1/2"cordless impact gun, but it didn't have enough nut to turn the engine over., so I picked up a leakdown tester:
1: 8%
2: 18%
3: 2%
4: 8%
Cylinder 2 is a little concerning. I could hear and feel air coming out of the exhaust ports, always on the front valve for each cylinder. I'm not sure what to make of that trend.
I also sent out an oil sample to Blackstone for analysis, so I should have a better sense for the health of the motor.
Today I finished stripping all the accessories from the motor and separated the head and oil pan from the block. Now I have a minor roadblock until I go out and buy a E10 socket to remove the main bearing support plate.
Things look remarkably clean under the valve cover, compared to other pictures I've seen. None of the brown/orange staining of the cast parts. Lookit dem cam caps!
Combustion chambers seem... unremarkable to me. They look fine, I guess. Nothing caught my notice that would have caused the 18% leakdown test result on cylinder #2 from the forward exhaust valve.
This seems like significant carbon build-up on the piston tops.
I don't feel a lip on the cylinder walls and the crosshatching has nothing obviously wrong with it that I can see, but I'm a to engine internals.
Inside of the oil pan looks sludgier that expected.
Off to buy an E10 socket and contemplate compression ratios. Supposing I stuck with 250 hp, would the 10:1 help give me all the spools and all the torques? Or should I succumb to "while you're in there" and get some 84mm 9:1 forged pistons so have headroom for ALLOFIT later on?
Alright, updated plan of attack. Nothing here is original, I'm mostly just writing stuff down to make sense of it while I research and document my reasoning for future reference. I'm breaking things out into stages to spread out the and get a better sense of timeline.
Goal: Make as much power as a Miata-based driveline can handle reliably for street, with occasional autocross, drag, and possibly a track day. ~250hp
Supporting mods needed
Upgrade from MS DIYPNP to MS3 to control VVT. In the interest of only changing one thing at a time it may make sense to do this before the VVT engine goes in the car, to work out any glitches with MS3 installation on a my known working 1.6L.
VVT swap parts: throttle cable, alternator, motor mounts, fuel rail, etc.
6-speed Transmission. This is going to be my main bottleneck for power, as most stronger options are too pricey. I have a functioning (albeit with crunchy synchros) 5-speed in place, along with a spare 5-speed in my garage. I'll probably sell the spare and be on the lookout for a 6-speed.
Supporting mods already in place:
Ducted SuperMiata crossflow radiator and homemade coolant reroute (reuse). Not interested in cutting up my hood for vents.
FM2 clutch Happy Meal: should be strong enough.
4.10 Torsen swap. Good enough for now. Will want to upgrade to better gearing at some point.
FF640 injectors - should have plenty of headroom
Fab 9 intercooler
FM silicone charge piping
Home made 2.5" downpipe to 3" exhaust. This will likely need to be modified, if not totally remade.
Turbosmart BOV
Moroso catch-can
GTX PCV valve
Phase 1: Bottom End
Parts
Manley rods - fix weakest link
Supertech Pistons with Wiseco XX NPR rings. Primary motivation for this is to lower compression ratio from VVT's 10:1. Leaning toward 8.6:1, 84mm but need further research to decide. Had I plannedbetter, I might have picked up an NB1 motor instead.
ACL bearings and ARP hardware
Machine services - special equipment for jobs I can't/won't do myself.
Clean and inspect block
Bore to fit pistons
Hone mains and check bearing clearances
Set ring gaps
Paint and assemble
Phase 2: Head - Mostly going to leave this alone, I think.
Parts: none? Besides seals, etc.
Clean
Check valve clearances
Replace seals
Phase 3: Engine assembly
Parts
ATI superdamper
Oil pump? Not totally sold on this for $400 but will continue reading.
Gates water pump with cast impeller
Timing belt, head gasket, seals, etc.
Assemble
Phase 4: Turbo
Parts:
Leaning toward Kraken EFR low-mount
Kraken 3" downpipe, then figure out how to get it to hook up to my exhaust.
I think the BE pump could be safely skipped if you balance your rotating assembly and run an ATI damper like you mentioned. Just make sure to get a new OE vvt oil pump to go back together with.
Why a new OEM pump? Should I be concerned about reusing the pump that came with my motor?
Looks the bare BE gears are available separately. How hard of a job is it to install them in the OEM VVT pump I just puled off my motor? Less skill required than building the rest of the motor?
Why a new OEM pump? Should I be concerned about reusing the pump that came with my motor?
Looks the bare BE gears are available separately. How hard of a job is it to install them in the OEM VVT pump I just puled off my motor? Less skill required than building the rest of the motor?
I've always considered a new oil pump a no-brainer on a rebuild. I installed a used perfectly running bp4w in my car without touching anything except for timing belt/wp, and I regretted it quickly when I discovered it had oil pump relief valve problems. Took scary long to build oil pressure after sitting for a few days. I think I got my new pump for $180 through Mazda, makes awesome oil pressure and worth every cent.
As for dropping gears into a pump, I believe it's pretty simple but might even be cheaper to just buy a pump with their gears than it is to buy a new OE pump and install the gears.
@Fireindc , if I remember right, you went with forged rods and stock pistons on your car at similar power levels to my goals. Any regrets, now that you've buttoned the motor up and put it back in the car?
I'm still waffling on internals and feeling a strong desire to avoid the machine shop altogether by going the ball-hone route.
No regrets at all. I've yet to push this motor to 300+ whp, but I've been daily driving and tracking it around ~260whp for the last 2 years and the motor has held up great. I daily drive the car, so I appreciate that I can start the car when it's 20* outside and not have to worry too much about excess wear due to forged pistons.
So far so good. Time will tell, still going to up the boost soon, but I see no reason to run more than my current level at the track ever.
My logic when building the motor was to not overbuild it, as the rest of the drivetrain falls apart pretty quickly past 300whp and I'm not looking to go down that rabbit hole.
Subbed. This is a pretty interesting read. I purchased a 50k VVT motor from @yossi126 that should be on its way over soon. Also have a 115k mile 94 1.8 sitting in my shed waiting for judgement day. Right now I'm contemplating compression testing the VVT motor and possibly dropping it in as-is. I live on an island and am only planning for around 200-250hp. They say power is addictive though and you've got me interested in possibly buying new, or harvesting pistons from the 180psi across the board 94 1.8 for more head room. Im planning on running pump gas, 92 octane as that is what’s widely available. Professional tuners that are Megasquirt knowledgeable are almost non-existent here. Im wondering if 10:1 compression is too fine a line for me to risk blowing my new engine. Planning on getting it sorted first and wiring the VVT to my MS3 and reading, reading, reading before dropping in my gt2560r. Had that paperweight in storage for over a year now. BTW, my car is a 90 too. :3
Last edited by Metallic Fox; 08-02-2020 at 04:27 AM.
Recent progress: I finished tearing down the head and block today. I have a spare expendable 1.6 block and head that I plan to practice drill honing, valve lapping, and some mild port work on. Once I'm comfortable with that, I'll move on to the BP6D work.
I plasti-gauged the main bearings all at 0.015 and measured the main and rod journals with digital calipers - admittedly not perfect but I was consistently getting 1.9655" for the mains and 1.7685 for the rods. Best case measurement error on that is +/-0.0005. FSM spec is 1.9661-1.9667 and 1.7693-1.7699, respectively, so they're a touch on the small side if measurements are to be believed. Not bad for oil clearance from what I've read, but I'll see if I can borrow a good micrometer to get more credible numbers.
In any case, I ordered standard clearance ACL bearings, ARP fasteners, and Manley rods.
Next steps are to borrow a bore gauge to check the bores better, and start cleaning the head and valves. Also need to select rings.
Originally Posted by Fireindc
No regrets at all. I've yet to push this motor to 300+ whp, but I've been daily driving and tracking it around ~260whp for the last 2 years and the motor has held up great. I daily drive the car, so I appreciate that I can start the car when it's 20* outside and not have to worry too much about excess wear due to forged pistons.
So far so good. Time will tell, still going to up the boost soon, but I see no reason to run more than my current level at the track ever.
My logic when building the motor was to not overbuild it, as the rest of the drivetrain falls apart pretty quickly past 300whp and I'm not looking to go down that rabbit hole.
Thanks, that lines up with my thinking as well. I've got a possible line on some used OEM 9:1 pistons and that decision is being driven by the condition of the engine, a desire to avoid the machine shop run-around (rapidly inflating costs), lack of E85 in my area, and drivetrain. I currently have a 5-speed in the car (plus a spare in the garage) and a 4:10 torsen. I'd rather avoid the gearing issues of the 6-speeds and BMW-type swaps are just too cost prohibitive. We'll see how it goes.
Originally Posted by Metallic Fox
Subbed. This is a pretty interesting read. I purchased a 50k VVT motor from @yossi126 that should be on its way over soon. Also have a 115k mile 94 1.8 sitting in my shed waiting for judgement day. Right now I'm contemplating compression testing the VVT motor and possibly dropping it in as-is. I live on an island and am only planning for around 200-250hp. They say power is addictive though and you've got me interested in possibly buying new, or harvesting pistons from the 180psi across the board 94 1.8 for more head room. Im planning on running pump gas, 92 octane as that is what’s widely available. Professional tuners that are Megasquirt knowledgeable are almost non-existent here. Im wondering if 10:1 compression is too fine a line for me to risk blowing my new engine. Planning on getting it sorted first and wiring the VVT to my MS3 and reading, reading, reading before dropping in my gt2560r. Had that paperweight in storage for over a year now. BTW, my car is a 90 too. :3
Why not put the VVT head on your 94 block? Or swap the 94 pistons in?
ADAM: Thanks for the notes. We're pleased to be able to tell you this salvaged engine doesn't have any glaring issues. Most metals read a bit below averages, which for the Mazda 1.8L 4-cyl engine are based on ~3,700 miles of oil use. Even slightly higher copper isn't especially concerning for bronze parts. The flashpoint showed a trace of fuel, but that's okay. Small amounts like that can come from idling, short trips, etc. (anytime the engine doesn't get to full operating temp) and don't typically cause poor wear. The viscosity is that of a 0W/40. Good!
Plasti-gauge:
Also, this kitty right here used up about 8 of her lives this weekend. She slipped out of the house and got hit by a motorcycle while my kids (5 & 7) watched. I thought for sure she was a goner, she was limp when I carried her out of the road but started breathing again real ragged. The whole situation just about broke my heart, but after an X-ray and night at the emergency vet, she's going to make a full recovery. No fractures, just a concussion, some bruising, and fluid build up around her lungs. She spent a night in an 02 chamber and got some pain meds, but otherwise we just have to keep her calm for a week. She's one ******' nice kitty, less than a year old, with a great personality. We're glad to have her back.
05-17-2016, 09:00 AM
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to engine internals.
and get a better sense of timeline.
