14CUX MAF IAT Sensor???

[Grimace]

Hey quick question, does the MAF on the 3.9v8 have any form of Inlet air temp sensor?

I wish to splice into this sensor to connect it to my haltech interceptor. As at current it has no sensor/pickup for the IAT.


Cheers
Anthony

[PhilipA]

NO.
MAF (Mass Air flow ) sensors measure air mass which automatically compensates for density ie temperature.

Therefore the Haltech does not need this info on a MAF vehicle but does need it on a MAP( Manifold Absolute Pressure) sensor or flapper.

Regards Philip A

[Grimace]

NO.
MAF (Mass Air flow ) sensors measure air mass which automatically compensates for density ie temperature.

Therefore the Haltech does not need this info on a MAF vehicle but does need it on a MAP( Manifold Absolute Pressure) sensor or flapper.

Regards Philip A

The haltech can be further mapped to allow for variations in inlet air temp. I thought this would be good to auto lean when colder air temps are available and richen when hotter?

I really just trying to learn as much as i can about this software and basic tuning and thought seein as thou the software has the ability to change fueling and ignition percentages it may be of great benefit.

But alas, the maf has no air temp sensor so I guees that rules it out for now, Unless I fit a sensor to the manifold myself.

Cheers
Anthony

[PhilipA]

You could fit one to the air inlet of the air cleaner well away from the engine, but remember you already have correction for fuel temperature. On Motec installations I have seen the air temp sensor is at the air cleaner inlet.

I think you would have to be careful that an additional sensor did not work against others.eg the fuel temp sensor increases injector duration to compensate for reduced density of hot fuel. Although not a direct relationship generally on a hot day the fuel will be hot and vice versa.

Regards Philip A

[Grimace]

Thansk for the info Philip, Much appreciated.

I have now moved onto the Air Fuel ratio :D
As I am starting to gain confidence in tuning, I am toying with the idea of mounting a A/F gauge and getting right into the maps.

All i gotta do now is learn about what oxy sensor and gauges are compatible or if there even is any incompatibility with any. :angel:

Spent a total of about 8 hours to date reading up on stuff and only just got to the a/f segment in my agenda :D

I am currently running a map I spent about 3 hours compiling and so far it seems pretty good, I also advanced the timing another 2 degrees, but I think I may have leaned out a small section of the fueling, hence why the gauges are high priority.

Arghh, too many variables, too much to learn, hope I don't ruin anything :confused: :)

[PhilipA]

Grimace,
A/F gauges usually have a wideband sensor that comes with them. The most cost effective I have found is the NGK gauge.

see Ballenger Motorsports - High Performance Electronics (http://www.bmotorsports.com/shop/index.php/cPath/103_107)

I have not gone to the expense of buying one mainly because the 14CUX has a set maximum injector duration and this cannot be overridden without a chip change to a Tornado or similar. Interceptors cannot do it.

Also the 14CUX stops adding fuel over 5500?RPM Most power shown to be added by the before/after comparisons by people such as RPi are in this full throttle high rev area. How often do you drive at full throttle over 5000RPM?

Most of the performance increase you get with an interceptor with a 14CUX is from more aggressive timing.

Didn't you have your Haltech dyno tuned? If so your A/F ratio should be pretty well OK.

Regard sPhilip A

[Grimace]

Didn't you have your Haltech dyno tuned? If so your A/F ratio should be pretty well OK.

Regard sPhilip A

Yeah, but the a/f ratio on the chart isnt as smooth as it could be and I have had to adjust the damn maf a thousand times.

I also note that the dyno tuning was enhanced for higher throttle usage, which as you mention is hardly ever, the part throttle tuning has room for improvement IMHO.

I started toying around with the fuel and timing to make a much smoother map, as the original maps were bumpy as hell.
I have also increased the timing by almost 4 degrees since pickin up the car.

The present map (one I spent about 3 hours on) feels much better at 30% load and this seems to benefit my around town driving. Only thing now is I want to start fine tuning the fuel map and get it improved again.

To be honest I dont think enough time was spent tuning it originally at Graeme Coopers.
To be even more honest, I am more curious in learning now, any improvements will simply be a bonus.

I was up at 5am this morning, resetting and checking all my MAF voltages and I only had an Idle CO voltage of .67, so put that back up to 1.5v, and now the car is obviously running rich at light throttle. So I started compiling a reduced fuel map that I dont wish to implement into the interceptor until I have the AF gauge.

I could go on and on. :)