Sensory Deprivation

[ra23celica]

I have a long term project where I will be fitting a carby 3S-GE to my RA23 to run under Classic Rally Car regulations. Obviously, no ECU would be required but to me it seems a shame to waste all the sensors fitted to this engine and not be able to at least see their outputs. Are the sensors on this engine (most Toyota engines) configured in such a way that you can convert their variable voltage or 'on/off' signal to a number or indicator that can be displayed on a screen?
Or, am I better off just replacing these sensors with purpose built ones that feed a digital dash, for example.
I know that digital dashes are not period and not allowed, its just to try to explain my point. Thanks.

[jonathan yee]

Which gen ge? I have the bgbs for the first 3 gens if you need the specs for the various sensors.

[George]

Depends on what you want to know and whether these sensors are allowed by the regulations
Maybe it's worth looking at fitting obd2 compliant ecu with its loom and sensors, and running techstream software on a laptop for datalogging. That way you would be free of the need for any custom solutions

[ra23celica]

Jonathan - it's a Gen 3 3S-GE and a BGB for it would be a useful thing. But it you can give me any specs for the engine sensors for that Gen, it would be great. Thanks.

George - Primarily I would like to know A/F ratio, oil temp, oil pressure, water temp, fuel pressure and maybe detonation. The sensors allowed should not be an issue as long as the data they produce cannot to used to alter the performance of the engine in stage. Datalogging is a good idea, I would like to have a record of performance over time. Is techstream a cost effective / efficient solution? Thanks.

[George]

Techstream is official Toyota diagnostic tool. It's costly unless you know how to get it for free. It can only show you however the things that a particular ECU under test can output, and it only works with OBD2 cars (~1995 and up in USA, 1998 in Japan). Officially free software exists that works with OBD2 Toyotas. Overall, you pay only for a laptop/car PC and a cable which is $50 worth (Chinese clone for Techstream cable), or $10 in case of the free software. In this sense, Techstream is very cost effective.

Unfortunately only newer Toyota ECUs (say 2004 and up) can output AFR and knock info thru OBD interface, and they run costly O2 sensors. Not to mention that a typical Toyota ECU is not aware of oil temp or oil pressure. So running some typical 1998 ECU in factory configuration only leaves you with MAF or MAP reading, coolant and air temp, narrow band O2 sensor voltage (which is pretty much lean/rich indicator rather than accurate instrument), throttle position and that's all.

[jonathan yee]

I can upload pics for the various gen3 sensors. Or you can borrow it if promise to look after it :-)

[Hen]

If it were me I'd pull the factory sensors out and fit a bunch of gauges/datalogger, mounting the new sensors in the factory locations if possible. Unless you really like home electronic tinkering I think the work involved to display/record the factory sensors wouldn't be worthwhile.

Hen

[MWP]

George - Primarily I would like to know A/F ratio, oil temp, oil pressure, water temp, fuel pressure and maybe detonation.

The only one of these sensors the factory engine will have is the water temp.
Most aftermarket gauges use sensors with different voltage/temp curves to Toyota, so you wont be able to use it anyway.

You'll need to do as Hen said... just install normal aftermarket gauges and sensors.