Exhaust Gas Analyzer as tuning aid?
 

Hello everyone,

First time post, but long time reader:

Although I'm relatively new to 1/8 On road Fuel, I've been around the hobby for quite some time.

Reading through previous threads on engine break-in and tuning, I've been wondering if anyone has experimented with an automotive exhaust gas analyzer as a tool to optimize carb settings?

In theory, the O2 sensor's readings should tell us how close the A/F R is to a Lambda of 1 regardless of atmospheric conditions, or would unburned Nitro in the exhaust gases throw off the sensor as free O2?

I'm not entirely clear on the combustion chemistry when Nitro is involved.

Cheers,
-m

I've actually done this. The NOx gets maxed out and it wiggs it out, at least with the sniffer I used.

There are systems reading the engine temperature and adjusting the LSN in an electronc way.

Aradaiel,

I'm not all that surprised, a standard smog checker for a 4 stroke gasoline engine would probably see the combustion compounds from our 2 stroke Nitro engines as simply out of range.

Looking into the chemistry of Nitro fuel combustion:

Methanol:
2 CH3OH + 3 O2 → 2 CO2 + 4 H2O

Nitromethane:
4CH3NO2 + 3O2 → 4CO2 + 6H2O + 2N2

I would think that guys that tune professional 2 stroke race-bikes, might have the required gear.

The thing is- a simple O2 sensor would probably work, (although the 4 wire O2 sensor in full size cars would need more heat to operate correctly )



Roelof,

I've not run across any systems like you've described- are they for use on-board the car while it's running on-track?

I'd be interested in reading about them though. Do you have any links to manufactures of those kinds of systems?

Cheers,
-m

Back in the 90's I have read something about it on the Sgrid forums and there was a link to a manufacturer. Also the EFRA did mention last year such systems do excist but also I must say I havn't seen such systems today.

That thing from back in the 90's was a some kind of black box mounting in the fuel lineand connecting on the throttle plug on the receiver. It was a some kind of electronic LSN control and had an engine temperature compensation.

Just to log the engine temps, rpm etc: http://www.eagletreesystems.com/Car/car.html
But I don´t think there's any possibility for on-board adjustments.
Didn't Futaba make a system? :confused:

Sanwa does, the MT-4 has telemetry system with the temp probe, but its micky mouse probe, easy to break down.

I had a fuel injection in mind that Futaba developed, not sure how it worked or if it ever did. :tire::)

they where made by PC/RC "EFI-801" they work on jump switchs to set the proformance of the motor from the exhaust temp taken from inside the pipe near the exhaust port.
they also had the ability to set how the startup was from rich to lean... all you had to do was set the LSN so there was fuel spitting out of the exhaust and wind the HSN all the way out so the regulator would do the rest.....

they dont make them for the small engines but you can still get them for the large scale engines....

http://www.pcrcproducts.com/products.html

if they still allowed them ever man and dog would drive a nitro car.

my time using one you can get old motor that have lost there edge to go hard again for a while.

while the dollar is good i should send mine back to get fixed.