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i'm toying with the idea of getting a wideband for some mild DIY N/A tuning of my NA8. i'm after something with both wide and narrowband output so i can feed the narrowband signal back to the stock ECU. i plan to piggyback a jaycar DFA for tuning my AFR.

a few questions:
- can i bolt any wideband sensor into the narrowband sensor bung in the stock exhaust manifold?
- the innovate LC-1 seems to be the best buy for its price. any other recommendations? are there any other kits which offer a secondary narrowband output?
- other than initial free air sensor calibration, what else do i have to do anything else to get the LC-1 to work with the stock ECU, or is it plug and play?
- are all AFR gauges the same, or are cheap ebay ones going to give me inaccurate readings? i've never purchased an aftermarket gauge before.

thanks in advance guys

Locutus wrote:i'm toying with the idea of getting a wideband for some mild DIY N/A tuning,,,, i plan to piggyback a jaycar DFA for tuning my AFR.

for mild n/a tuning a wideband seems like overkill to me. i got some pretty decent results with my DFA using the stock narrowband sensor and a $15 jaycar afr display kit.

even better.

how do you tune with a narrowband? just make adjustments to keep it in the stoichiometric range?

zoomzoom, sabretooth, tinscfi, Big G, (I think) ampz, and a few others, including moi, has one.

You can use the LC-1 as a standalone unit with an accurate digital display to tell you AFR.
Pretty much all Innovate's products are amongst the best value out there, and the quality is top-shelf.
If you specify the make of your car, I'm sure Innovate will give you the correct Bosch O2 sensor to match the thread of the OEM bung, at least it does when you buy one with a MegaSquirt Plug N Play.

I have no idea about the "switchability" between narrow and wideband.

Why not have both plumbed into the exhaust?

Have you bought the DFA? have you considered going MegaSquirt?

I bought an AEM Wideband from the US for my Turbo NA6. I'm not sure if it had a narrow band output; but it was cheaper than the LC-1.

Just a thought.

the plan is, if i get an LC-1, to get the tune right by monitoring & logging AFR with a laptop. afterwards i'll hook it up to an AFR meter/gauge so i can keep an eye out for any nasties.

from my understanding, the LC-1 has two programmable analogue outputs. this allows you to set one to output to give a narrowband reading. i think it even comes setup like this out of the box.

as for why not have 2 sensors - simplicity, i guess. also if the sensor is a direct bolt in i can do it all in my backyard.

i've bought the DFA already. i considered a megasquirt but didn't go down that route due to cost and i don't really want to sacrifice OEM drivability on cold starts as the 5 is my only car. also sounds like a bit of a pain to get other accessories working like air con and power steering. the megasquirt unit looks like an awesome piece of gear though - if i ever get an aftermarket ECU, that would definately be it.

boags, what did you get specifically & where from? going from the official website, RRP on the AEM UEGO kit is US$400!

Locutus wrote: i considered a megasquirt but didn't go down that route due to cost and i don't really want to sacrifice OEM drivability on cold starts as the 5 is my only car. also sounds like a bit of a pain to get other accessories working like air con and power steering. the megasquirt unit looks like an awesome piece of gear though - if i ever get an aftermarket ECU, that would definately be it.

You will have issues to solve with the MegaSquirt kits that you build yourself, but not with the Plug N Play units.

As with all things in life, you get what you pay for. The DIY kits is less than half price, but then you have the issues you mentioned, the PlugNPlay is alot more expensive but you have next to no issues.

There is a company in Brisbane who is importing Innovate gear and their prices are very good. They don't put huge mark-ups/margins on the price.

Locutus wrote:boags, what did you get specifically & where from? going from the official website, RRP on the AEM UEGO kit is US$400!

I got the AEM UEGO with gauge from EBay US... Can't remember the price; but it was $20 more than the LC-1 (without gauge) from DIY Autotune.

Boags

I had an LC-1 in my supercharged NA, it was a nice bit of kit but make sure you follow the instructions when you install it (free air calibration etc).

Just for something compleletly different, my wideband is the 2A1 from this mob: http://www.wbo2.com , it was a diy kit and they are based in the ACT. Well priced and it has datalogging for o2 and several other analog inputs. Like most units it has the simulated narrowband output for the stock computer. Not a fan of having a gauge myself, but you can add one. I am planning on getting a new one for my Landcruiser, and will probably get the new 2Y kit because the 2A1 has been superseeded. The 2A1 has been in the 5 for a year and a half, never had a problem with it.

Locutus wrote:...from my understanding, the LC-1 has two programmable analogue outputs. this allows you to set one to output to give a narrowband reading. i think it even comes setup like this out of the box...

Yeah i'm keen too, does anyone have the settings to adjust the simulated narrowband output to suit the MX-5s ECU?

Locutus wrote::shock:
even better.

how do you tune with a narrowband? just make adjustments to keep it in the stoichiometric range?

sorry for the slow reply.

first off i would say that i have some reservations about your planned course of action. sticking in a wideband with a simulated narrowband output, and then using the dfa to tune that simulated narrowband output (with the guidance of the wideband via datalogging on a computer)... it just seems like a very convoluted process to me. why not just tune off the narrowband - because at the end of the day, you will be using the dfa to modify one or the other narrowband signals.... so why not just stick with the oem sensor / signal.
this is the umpteenth time i've gone over this , i should probably give it it's own thread to refer to in future.. save me having to type it out every time.

anyway.....

dfa built and installed




el cheapo jaycar AFR guage built and installed






ok so in the above shots you can see the gauge in closed loop cycling between green (lean) and yellow (rich), with several red leds in between . the mid point of the red leds is somewhere near stoich.

so when you put the boot in we go open loop and the car goes rich (yellow leds). so you take note of the corresponding tuning points on the dfa, and simply adjust these points until the yellow leds don't light up anymore.

i did this by doing laps of 2 on/off ramps of the western ring road here in melbourne, stopping in between to make adjustments. took me half an hour or so. i leaned it out to the 2nd last red light on my afr... it gave a noticeable improvement in power. probably could have gone further but i figured better safe than sorry.

later on i replaced my stock injectors (215cc from memory) with some big 460cc injectors, in preparation for a turbo install. the car would barely run when i first started it, coughing and spluttering as it was drowning in fuel. it took about 5 minutes tuning with the dfa in the garage to get it to idle and cruise... then took it back out to the freeway on ramps to tune again. another 20 / 30 minutes of WOT tuning and it was back to it's old self.

ok so i don't have any dyno charts to measure my results but another forumite , phil / manga_blue followed the same procedure in tuning his na8 with the dfa / narrowband afr meter combo. he recorded his setting and then zeroed out his dfa. then put his car on the dyno , had it dyno tuned and ended up with a tune that was almost exactly the same as his initial tune.

so yeah, for a lightly modded car i reckon you can get by with a pretty simple , cheap solution. for a heavilly modded car, a megasquirt or something is probably better but there ya go. you don't need to do much i reckon, the mazda engineers got it pretty right to start with, they just added some richness for safety, which can be easilly dialled out with the dfa.

thanks for the writeup fatty - really appreciate it! i've done alot of searching in this forum previously about DFA tuning but didn't come up with much.

i wasn't aware that you can get a mild tune out of a the stock o2 sensor - you may have just talked me out of buying an UEGO/LC-1.

for those who are looking to buy a wideband sensor & gauge setup, the AEM UEGO seems to be the best bang for buck as boags suggested above. it's basically the same as an LC-1 but with only a single analogue output (one output of the LC-1 would probably be used to output to a gauge anyway) and the controller is built into the included gauge, making it really easy to wire up. the AEM wideband sensor is also comes calibrated from the factory, so there's no need to remove the sensor from the manifold to do periodic free air calibrations like on the LC-1.

AEM UEGO instructions (PDF):
http://www.aempower.com/images/products ... 0-4100.pdf

Innovate LC-1 instructions (PDF):
http://www.innovatemotorsports.com/supp ... Manual.pdf

I bought the tech edge kit and wired it all up myself. A big advantage for me was the additional softawre and logging available.

Definately worth a look - fairly priced too.

The LC1 is programmable on both outputs.
I have the narrowband output hooked up to the same air/fuel guage Fatty mentions above.
Although I've massaged the AFR range beyond the narrowband signal (19:1-11:1 AFR) accross the ame voltage range as the narrowband.

It is pretty fast and accurate too.

Narrowband will be fine for an NA application though.