MattyRedlocks' MX-5: Moxxi the NB

[mattyredlocks]

Kickbacks? Maybe we could work something out...

[MattR]

Or hawk HP or HPS, order a couple of front and rear sets, which they do as a package, at a time to save on shipping through Hawkpaddirect.com and cheaper than most other decent pads. Just be aware that delivery time can be a bugger.

They are what I ran in my NA6 for both street and track and I never got fade, they didn't chew rotors,weren't noisy, were a little dusty on the track but fine on the road and worked cold. I wasn't gentle on them either.

[mattyredlocks]

Change of plans!

...again.

So after the car developed an exhaust leak post clutch job, Andrew and I got it up in the air with a view to putting in a new gasket and smothering it in goo. I had already identified that it was coming from the flange between the headers and the cat pipe (which is just before the o2 sensor on an NB8B), so it should have been an easy job. Three nuts, bit of force to get it off the hangers and problem solved, right?

Yeah nahh, mate. Studs are rotating, mate.

I decided then and there that rather than pull of the headers and fix the studs, I'd just go and buy that new system I'd wanted (but not wanted to buy just yet). Figure if I have to pull it off, might as well be putting a new one back in, right? Called up Auto+, picked up a full racing beat system the next day:

(Well that's the headers anyway)

Fast forward to Saturday, and the car is in the air again. Also we can't get the nuts off the studs. Queue kicking and screaming. We thought only the one was rotating, turns out all three were.

No worries, I bought a nut-splitter. ...nope, that didn't work. Nuts were a funny shape, couldn't get the tools (and hands) in there. Great.

I had this brilliant idea of unbolting the headers, unbolting the cat pipe from the mid pipe, and pulling the whole lot through the engine bay. Nope, the cat is too fat, wouldn't clear the subframe/gearbox. Great. Queue more kicking and screaming. Oh wait, let's try the nut-splitter again! Nope, that broke. Thanks Supercrap.

Next idea was to bolt the headers back on, drop it down, try something -anything- to get the nuts to move. Managed to wedge a screwdriver in the flange enough to get tension on the nuts, so we could rattle gun one off. Yay, one out of three! Prybar in this time, let's get the next ...snap goes the stud. That's ok, the bugger is off. Yay, two out of three! Pry bar back in, let's try for gold... Nope. Nut is rounded. Oh dear. No matter, time for Matt to use his viking strength to just lever the pipe and snap the stud:


ƒü¢k. Queue more kicking and screaming.

That is a bent flange, one very bent stud, but no joy is to be found in that image.

Seeing our victory near, we unbolted the headers from the motor again, pulled it up through the engine bay as far as possible - and finally snapped the stud off. Queue me throwing the cat pipe across the lawn and into the night. At this point we left to get something to eat, what was going to be a couple hour job had been going for four.

What's that you say, we should have just cut it? Yes, in retrospect, we should have. Problem was, we didn't have a hacksaw or grinder. It was too late to go buy one, and of course, in the heat of the job, leaving to get one from someone else and coming back "would take too long". What foolish men we were.

Coming back to it, should have been a very easy job just dropping the new headers in and bolting up the mid/cat pipe and muffler, right? Nope, NB8B engine bay strikes again:

Stupid aircon lines.

In the end we had to unbolt the aircon line mount, the dryer can, and (not so gently) push everything out of the way to get the damn thing over the studs. Once that happened though, the rest was easy-peasy:

Shiny.


More shiny.

Not bad considering this is what it started with:

So boring, really.

All in all, 0/10 experience, would do again but I don't want to. I can't thank Andrew enough for helping me through this one, there were multiple occasions where we both just wanted to set fire to the bloody thing and walk away. So thanks man, I owe you one.

This picture sums up the experience pretty well, I think:

[bruce]

OUCH!

[MattR]

No fire, sparks or blood no care.......

[speed]

Sucks big time when a few bolts cause such grief. I can totally relate. In a way I'm glad I'm not the only one that has suffered this pain.
Glad you over came the "issue" and ended up with something that both looks cool and increases performance.


Sent from my GT-I9506 using Tapatalk

[mattyredlocks]

No fire, sparks or blood no care.......

Well, about that...

There might have been some knocks and slips that resulted in some blood and bruises. So much under that car is pointier than you think.

Because reasons.

[ManiacLachy]

... leaving to get one from someone else and coming back "would take too long". What foolish men we were.

Ahhh been there, only to spend way longer making the situation far worse than it had to be. If moving something out of the way helps, move it - now. If you don't have the right tool, go get it - now. I'm still re-learning the lessons every time work on the car

Glad you got there in the end. Hows the change? Nice noises? Any improvement on the butt-dyno?

[mattyredlocks]

Glad you got there in the end. Hows the change? Nice noises? Any improvement on the butt-dyno?

Honestly, could not care less about the sound. There's a reason I kept the stock exhaust for so long.

I can confirm it does sound different though; sounds deeper when blipping on a downshift, way louder under load and in high revs. Idle and coasting is about the same though (which is nice), however the reverb when crawling out of my garage (level two basement of a big apartment block) annoys me. How people live with stupid loud cannons, I'll never understand.

As for power? Eh. The car feels better than it did with a pre-o2 sensor leak (that caused all kinds of weirdness), couldn't tell you what it did over the non-leaking stock system. Racing Beat's dyno charts showed something like a 4.3% and 4.5% increase in power and torque respectively, but that was also on a non-vvt motor.

In any event, the car isn't leaking and leaning/riching out because of it any more, so that's a win.

[mattyredlocks]

In any event, the car isn't leaking and leaning/riching out because of it any more, so that's a win.

HAHAHAHA RIIIIIP.

So the car was in fact leaning out, which I think developed after the exhaust job, not really sure. I believe I have now fixed it though, so I'm purely putting this up here in case someone else has the same issue.

The Issue:
- Car would start, stumble, surge, stablise. This happened infrequently, but recently became just about every cold start, and some hot starts.
- Car would lean out really bad randomly for 30 seconds or so every now and then under part throttle or idle - we're talking AFRs of 18-20.
- Car was running leanish most of the time, sitting in the 15s for the most part when in closed loop.
- Above leaning happened when warming up, warm, heat soaked, under load/not under load, pretty much any time in closed loop.
- Car ran fine at full throttle (open loop), dumping fuel in as it should.

Initially I thought it might be a busted air temp sensor since a mate had a kinda similar issue and that was the cause - tried two secondhand ones and the issue persisted.

Thinking that it had to be to do with a sensor (since it was fine in open loop), and the o2 sensor was clearly working, I took a stab at it being the Mass Air Flow sensor. Getting these new requires drug money from Mazda or Supercheap ($500-$800!), even second hand they're not cheap. Initially I thought I would just buy some MAF cleaner ($30) and try that, but then I found some aftermarket MAF sensors on eBay for $35. Figured bugger it, why not. Got it in the mail last night, whacked it in.

I *think* the car is good now. Only taken it on one drive since, but the car did not stumble on start at all, part throttle under load I was seeing AFRs in the 12's and 13's instead of high 14's and 15's, and there were no 'major lean' episodes of 18-20. Going by just watching the gauge while driving around, I saw a lot more 12's and 13's than I have been seeing int he last couple weeks, so all signs so far are pointing to it working.

I should point at at this juncture that the car is still running a stock ECU - yes, I know, all of this would have been much easier to diagnose if i had datalogging out of an aftermarket ECU. This is the plan for the new year, once the waterpump/timing belt/coolant re-route job is done.

More will come later, once I've dríven it a bit more.

[mattyredlocks]

Well that didn't last long.

New MAF has made the car run worse. AFR is all over the place once the car has been dríven for a bit, even riched out so bad it wouldn't idle.

I'm chalking this one up to 'this is why eBay knock-offs aren't always a good idea' .

The stock MAF will be going back in, and I may or may not run some MAF cleaner through it first. Honestly, contemplating not even bothering. I'm about to leave the country for a few weeks, and I think when I return I will purchase that Adaptronic...

[Magpie]

The joys of modding Good to see that you put up both the good and the bad. At least when you get back it will be where you left it

[mattyredlocks]

I'm back!

Drove over 3000km all over America (in a Mustang, Buick tank-couch-thing and in a Dodge Charger), blimey the interstate highways are different to ours. The sheer lack of adherence to speed limits was a bit of culture shock, but we quickly got very used to the 90-100mph highway cruises. Some of the roads were so damn straight though, didn't even need steering input:



One of the highlights of the trip was definitely hooning on the Angeles Crest Highway (the mountains north of LA) on the way back from Vegas:



Just think Lakeside, but it goes for miiiiiiiiiles. Not as tight and wiggly as Nebo, but way higher speed corners. The road was immaculate (which is saying something, so many American roads were absolute trash), cambered well and wide. I can confirm that Mustang's don't quite turn that well though, really would have been great in an MX-5. Oh, I did actually find one at the top (supercharged too):



Once back, I got stuck into installing the Adaptronic. Easypeasy, ran a map line and done (the MAF has since been replaced by a piece of straight ally pipe):



Tuning however, was not as easy. The base map is a little bit bleh for the VVT donk, but with a couple net-sourced and friend-sourced maps (plus a lot of road tuning), I've got something that starts and idles very nicely, and butt-dyno says makes more brap up top. Don't know if it actually does, but just having a car that runs right is nice. I did take some logs of WOT acceleration in 1st, 2nd, 3rd and 4th with the stock ECU - I'll do the same with the new tune (via the same external datalogger) and see if the numbers are significantly different.

For now, obligatory 'It runs and doesn't stall or explode' pics:





For now, that's it. She runs. Next is water pump/timing belt/front main seals job, followed by new brake pads. Then, supercharger time.

[mattyredlocks]

Quick update (because I forgot to the other week):

Installed new rotors and pads on the front (QFM A1RMs), bled the entire system (thanks Jamal and Kirk, especially Jamal for checking I put the brakes back together properly) - turns out the old fluid was actually pretty OK this time, not even a little bit feral.

First flying lap of the first session at Lakeside two days later I had a small moment of terror - jumped on the stoppers coming into Karussell, had plenty of pedal but the car didn't slow down as much as I anticipated... Pro tip: bed your brakes in at high speed, apparently doing the 80 - 40 jumps like the box suggested wasn't quite enough. Second session though, brakes felt great. Nice to have working brakes again.

Tuning still going well, got the map to a point now that I am very happy with, just needs some fine tuning before adding the flex sensor and starting on e85.

[mattyredlocks]

Good day at the track yesterday - nothing broke, didn't hit anything (despite my best efforts at one point):



Car is running very well, tune is coming along nicely. I'll make a bigger post about it later (maybe), but I've been writing scripts to tune the car for me. Essentially analysing log files to generate/calculate various maps and settings; most useful of which has been my script to generate a new fuel map from the current map and logs. This script has gotten the car to a state where I'm hitting the target AFRs most of the time, and it's very, very street-drivable.

Future plans have changed though, E85 is no longer going in the car (straight away). I may have bought a thing:



Factory SE turbo. Came with some exhaust piping (which will be cut to fit my Racing Beat mid pipe), and I've scored a factory intercooler system donated by Lokiel.

Plan is to get a new (bigger) intercooler to match the piping, an electronic boost controller, and run at it at around the 10-12psi mark - then put E85 in. I'll pull the motor to weld an oil return onto the sump, and do all those other jobs I've been meaning to do (timing belt/water pump/coolant re-route, etc.) while I'm there.

I know what you're thinking - why put an SE turbo on? Aren't other turbos going to make much more power? Yeah, they are. But I'm not chasing that. I want more power, not all the power. This turbo should be able to double the power the vvt motor makes now, and (hopefully) not throw a rod. A year ago I wouldn't have considered it, but after driving an NA8 (Jamal I'm looking at you) with a running-at-wastegate-pressure rip-off Garret turbo that spooled way too high in the rpm range - and having the time of my life with giggles - I reckon this one will do fine. Anecdotal evidence suggests a new ECU and a bit more boost gets SE's over the 200whp mark without too much hassle, tuning the vvt right and running e85 will net me a fun car no doubt.

I'd like it in before the September QR track day ...but we'll see what happens. More to come.