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Force Fed Mopar
09-03-2011, 11:36 AM
Does this need to be modded at all for larger injectors? Also, does it pull or add fuel as the temp increases? You might think it'd pull it to keep the afr the same, but I thought I read somewhere once that it actually added some to help keep combustion cooler? :confused:

zin
09-03-2011, 03:54 PM
I don't know, but from what I can recall, it is such a slow reacting sensor, that it pretty much just adjusts for heat-soak, but I can see it having some effect while in "cruise mode"/steady state. I would also expect that it would be modifier that uses another value that already takes the injector size into account, but that's just logic, which isn't always what wins out in a big company!

Mike

Force Fed Mopar
09-04-2011, 02:00 PM
It is a modifier, so I guess it probably doesn't need to be changed for injector size. Still wondering if it pulls or adds fuel.

Aries_Turbo
09-04-2011, 02:29 PM
it doesnt need to be scaled.

it adds fuel as the temps get colder. the only person ive talked to that needed to change it was larry buford and it was only when it was really cold out he needed to add some fuel.

Brian

Aries_Turbo
09-04-2011, 02:39 PM
also, aftermarket sensors have exposed thermistors and react quickly but you need to secure the thermistor somehow.

i got one like this from advance. and i wrapped electrical tape around one of the "legs" of the thermistor shroud for electrical insulation and protection and zip tied the thermistor to the leg for stability.

mine reacts fast.

Brian

zin
09-05-2011, 12:53 PM
Do you know if it adjusts timing as well? Most other engine management systems add timing when it is cooler.

I'm wondering if ours does both as well ... I guess you could chill it while it is running and its hole plugged, while watching a scanner ...

Mike

Force Fed Mopar
09-05-2011, 12:56 PM
AFAIK it does not modify the timing at all.

ShelGame
09-05-2011, 07:38 PM
It does nothing to timing. It only affects fuel with that one table and there's also a boost vs. charge temp table that usually cuts the boost off if the charge temp gets too high (in stock cals).

The charge temp table is setup to increase fuel with colder temps. I have the CTS in my Daytona, but I don't use it (It's ignored in code). Everytime I've logged it, it simply tracks coolant temp, although many degrees cooler. It really only measures the manifold (metal) temperature, I'm conviced. I have a sensor from a different Mopar (truck maybe?) that has an exposed thermistor with a small plastic cage around it. It might work better and I've been meaning to try it.

Mostly, I wanted the charge temp to calculate the turbo efficiency and operating point. Theroretically, if you know the presure ratio and the temperature ratio across the compressor, you should know everything about the operating parameters of the comperssor. I would probably need to measure the charge temp closer to the turbo for that, though.