Cheap Wideband Alternative - SLC Free

[Hazwan]

In my attempt to tune my own OBD1 converted A18A Lude, I went looking around for the cheap and reliable wideband as most of the popular ones are super expensive here. You guys know how cheap I am with stuff :p I make things work.. cheaply and still as good as the expensive shit

I ordered this kit from 14Point7 | High Performance Tuning Tools for High Performance Engines and the product is called Sigma Lambda Controller Free or SLC Free for short. It costs like $35 without the LSU 4.9 sensor and you can have it ordered with the sensor for only $50 more which is CHEAP! Sigma Lambda Controller Free | 14Point7



It came with 3 versions, SLC Free A, SLC Free B and SLC Free C

"A" is open source and displays in bar graph while "B" is closed source but displays the lambda and sensor temperature in numeric display. I recommend you to get this version as its easier to read instead of guessing what the bar graph is displaying and its only $10 more than the "A" version

Version "C" is the same closed source and displays in numeric display but only supports LSU 4.2 wideband while both "A" and "B" supports the LSU 4.9. I don't feel like explaining the difference between the two sensors but lets just say the 4.9 is newer, better, lasts longer and more accurate and you don't need to calibrate the sensor at all. More about the sensors here: Bosch LSU 4.9 is superior to LSU 4.2 sensors - ECOTRONS

Product features:

• Compatible with all fuel types
• Lambda Range: 0.68[Lambda] linear to 1.36[Lambda]
• 0.01 Lambda accuracy without the need for any calibration
• O2 Sensor Temperature Monitor
• Linear output allows easy interfacing with gauges, fuel management systems, and dataloggers
• Linear Output: 0[v]@0.68[Lambda] linear to 5[v]@1.36[Lambda], 10[AFR] linear to 20[AFR] equivalent for gasoline
• Simulated Narrowband Output allows you to install a Wideband O2 Sensor in place of your Narrowband O2 sensor
• Switch point @ 1[Lambda], 14.7[AFR] equivalent for gasoline
• 2 line backlight LCD display - displaying Lambda with 0.01[Lambda] resolution and displaying O2 sensor temperature with 1[C] resolution

I spent only $101.75 for SLC Free A with LSU 4.9 sensor shipped to Malaysia. Considering the popular wideband would cost at least $250 here.. yeah you know why I went with this. Oh and the LSU 4.9 sensor alone would cost $100 here! The only downside is you have to solder the components yourself. Not a huge issue for me as I 've been soldering stuff since I was 8

This is how I got it




All the components


PCB


All components soldered

[Hazwan]

It works!


I then noticed something missing from the package.. the actual sensor. What?

Quick email to the seller and he agreed to send the sensor which results in another 11 days of wait on top of the 16 days to get the kit in the first time. Sucks I know but oh well at least it got here and I guess the seller is being helpful about this issue too. He could have avoided this mess in the first place but oh well just my luck.

11 days later and here it comes, brand new LSU 4.9 with the box


I replaced the display with one with red backlight I have lying around and it looks cool


Soldering the components was easy. The spacings are good and nicely labelled. If you could read instructions and could solder properly then you wouldn't have any issues with this. It came with everything you need except a case for it. But then considering the price.. yeah no biggie.

Which brings to this, I found this nice 3D print design for the housing and I have it printed at the local place and this is how it looks like:





I wish they would offer an alternative to get a nice case for it for extra but hey the price!

Here's where I got the design from: DIYEFI.org Forum - View topic - My open source Wideband Controller, SLC Free

I wish it would have an option to customize the display or output but they have another product with all that fancy features. I don't need that. I just need a linear output from 0-5v to my ECU so I could datalog and tune. I didn't even need to see the display but I wish it would display in AFR instead of lambda as I'm used to AFR reading. That nice temperature display for the sensor is a nice touch.

Oh it also comes with a simulated narrowband output 0-1v but I don't use that. I won't be installing this kit in my car permanently but I might change my mind someday.

So yeah I gotta say the kit works really well and the customer support is pretty good. If you're looking for a cheap wideband and doesn't mind messing around with soldering and stuff, give SLC Free a try.

BTW heres datalogging in crome pro. I had it displayed in lambda as I needed to make sure its properly calibrated with the display on the SLC Free. And it does!


I'll update this thread with more pics and when I finished with the case and how to hook everything up to the ECU and everything.

[MessyHonda]

after many years I also bought a wideband. should of done it a long time ago. make tuning so much less guessing. i like how you built yours for almost half the price. over here mine was 180 and comes with touch screen display and 52mm gauge.

[Dr_Snooz]

Stickied. Good stuff Haz.

[Oldblueaccord]

Good write up!

Looks like a nice product.

I have used the Innovate one now for years but Im pretty much over there products and now ZERO customer support.

[Fixedit]

Wow, thank you for this! This is perfect as I've been dreading having to put some dinky round gauge somewhere on my dash for an AFR gauge, I think I'll do this and somehow fit the display in the dash-clock for the 3g. Awesome!

[Hazwan]

after many years I also bought a wideband. should of done it a long time ago. make tuning so much less guessing. i like how you built yours for almost half the price. over here mine was 180 and comes with touch screen display and 52mm gauge.

Man that fancy wideband would cost me at least $400 here I'm sure of that. Even the basic LC-1 is like $250. But yeah it would be impossible to tune without the wideband. Carb tuning maybe, if you are experienced enough to read plugs and all but its impossible to do that with EFI.

Wow, thank you for this! This is perfect as I've been dreading having to put some dinky round gauge somewhere on my dash for an AFR gauge, I think I'll do this and somehow fit the display in the dash-clock for the 3g. Awesome!

I hate having a bunch of random gauges on my dash too! I don't plan on leaving the wideband in the car permanently but if I ever change my mind, I would figure out a way to make it look factory too.


Anyway I've got the unit mounted inside the 3D printed box (wasn't that cheap for a piece of box but hey it looks cool and beats the homemade look)




They mentioned to not use the included Molex connectors as they are known to cause issues and recommended to just solder the wires to the PCB directly. I decided to use these fancy milspec connectors from ebay for like $5




Mounted on the car








I'm missing the black mesh sleeve for the cables but other than that its finished.

Oh I forgot to add that the cables aren't included so keep that in mind if you're getting the kit. Depending on where you look, the cables can be expensive but I just happen to have these cables from my old ass computer speakers and it have the right amount of wires and gauge for it. Total cost = free!

And heres my AFR after like 10 datalogging session and editing. Not bad for a first timer. I'ts getting pretty close now. I just need to fine tune here and there so it would be smoother but its wayyy better than what I started with the hybrid P75/P28 map where it would be rich down low and leans out in the mid range then goes stupid rich on WOT. My plugs were black lol

I'm going to do a quick write up on how to do your OBD1 conversion and get your ECU chipped and then tune it. I'm not a pro but I know a thing or two about this now


Please excuse the crappy pics. I only have my shit 3 year old phone as my camera now.

So far I've only spent around $130 for the whole thing with the box and fancy connectors. You can do it cheaper if you use some generic project box or even mount it elsewhere behind the clock maybe

[Hauntd ca3]

looks like a good starting map .
Not familiar with how crome works , with the adjustments , dose it give you injector pulse width numbers , afr , ve or lambda numbers to change around for the adjustments ?
Have you checked out hpacademy.com ?
i am putting myself through the tuning courses so i can do my own car and branch out and tune other stuff .

[MessyHonda]

man that box looks awesome. I cant wait to start tuning mine. looks like that is a very nice map. just got to tune that WOT

[Fixedit]

Just got mine in the mail, looks like a great product for the price. I'm excited to get it put together! Not only is the price good, but their shipping is nice and cheap, too.

[Hazwan]

Just got mine in the mail, looks like a great product for the price. I'm excited to get it put together! Not only is the price good, but their shipping is nice and cheap, too.

That's awesome! Remember to post pics.

Let me know if you have any questions about it

[Fixedit]

Heyy digging up this old thread. I’m finally getting around to putting this thing together (life did a bit of “life” there for a bit). Only thing is, I have no idea which wires from the 6 AWG 20 (for the sensor) go into which points on the PCB? I see in the 5 pin connector you have power & ground on the top two (and that’s all I’ll need for now as I’m not using this for input to an ecu) but I am completely lost on the 6 pin connector and it came with no instructions. How did you figure it out?