MAT Sensor

[tazgn]

I just wanted to share a recent experience. I've had my FAST system for about 2 years now and had been running the MAT sensor at the K&N filter. I always figured it wouldn't make that much of a difference if it was there or in the up pipe. Well, like most things in life I was WAAYYYYYY wrong. I had time the other day, and relocated it into the up pipe. I went for a drive and it drove like a new car. Idled GREAT, accelerated great. I thought it may only make a difference when I really got into the boost, but it makes a HUGE difference just putting around town in stop and go traffic as well. So anyone out there who was like me and thought it wouldn't really matter, take my advise and put the MAT sensor in the up pipe like everyone else has recommended.

Derrick

 

[bruce]

The closer to a intake valve the better.
ie in the upper plenum, but you need to use due care, it's thin.

 

[V6UnderPressure]

Howd you mount it?

Im going to ACCEL DFI, will it work the same with this kit? How did you mount it on the up-pipe, and where and how is the best place to mount it.???

Thanks

Scott<----newbie to DFI

 

[tazgn]

I mounted it in the pipe from the front mount IC to the chrome up pipe kind of down out of the way (for the "show" part of the buick). I figured it would at least be a good representation of the inlet temp there. All I did was drill a hole, bore it out to big enough to get the sensor in, and then JB weld the sensor in the hole. Works great. It's located down near the connection for the radiator fan physically. I have to agree with Bruce though, the closer to the intake valve the better. So closer to the intake is best. As far as the Accel DFI, I don't know. I've never worked with one. But I "think" the same principle applies.

Derrick

 

[Chuck Leeper]

MAT sensor location

Scott, i made an aluminum bung and welded it to the up pipe right at the T/B. [I have a PTE ft mt and the up pipe is 3" alum.]
No B4/after comparos as I did mine when I put the FAST system on.
Not "stealthy", but neither is the ft mt, the A/C eliminator nor the BG intake and a 70mm T/B!!
My theory: Scare'em to start with!! And then they become REAL believers when they get had by the DARKSIDE!!

 

[V6UnderPressure]

A dumb quesion, but haveing that right in front of the throttle body, does it throw off air flow into the plenum at all??? Not necessarily restricting airflow, but throwing off the flow % of each cylinder???
Thanks for all your tips!
Scott

 

[Chuck Leeper]

AIR FLOW DISRUPTION

being that it's so small and the turbulence involved in the incoming air at 20spi, I'd doubt you could measure the difference.
The boss I made keeps all but the tip outside the pipe.

 

[Iceman]

Chuck Leeper was that with the stock ecm or a FAST system.Did it make any difference in performance?
I would like to do mine and mount it in the plenum if it helps.

 

[BoostKillsStres]

Iceman, as Chuck stated in his post he moved it to the uppipe the same time he added the FAST.

 

[bruce]

Originally posted by Scott4DMny
A dumb quesion, but haveing that right in front of the throttle body, does it throw off air flow into the plenum at all??? Not necessarily restricting airflow, but throwing off the flow % of each cylinder???
Thanks for all your tips!
Scott

At all?
Ugh, ya, but not that you, or the engine would notice.

In some of my data logging, I've seen the MAT temp change 70dF in the plenum, during a run.

When they're mounted by the air cleaner they show only a few degrees difference.

I've heard some say they only see a 40dF change in the up pipe. Any further comments from the uppipe, stock intercooler crowd would be appreciated thou.

 

[Otto J]

they say that there is no correction factor setup at this time,but i was out tonight i have my full throttle set at 11.7 and it is always within 2 percent change , but tongiht it was cool out and now my a/f is down at 9.8 with no other changes?
anyone?

 

[S2V6RACER]

Re: MAT sensor location

Originally posted by Chuck Leeper
Scott, i made an aluminum bung and welded it to the up pipe right at the T/B. [I have a PTE ft mt and the up pipe is 3" alum.]
No B4/after comparos as I did mine when I put the FAST system on.
Not "stealthy", but neither is the ft mt, the A/C eliminator nor the BG intake and a 70mm T/B!!
My theory: Scare'em to start with!! And then they become REAL believers when they get had by the DARKSIDE!!

Chuck, when they start asking too many questions that's when you slam the hood down on thier head.

Bruce, I started putting MAT on my logging dashboard(I am running C-Com DOS) and I noticed ABOUT a 30 F rise running 30psi on a upper 70 degree evening. My second run(minimal cool-down time) ended up with a higher MAT reading (start of logging) but the end of run temp was close to the same(within expectations). I would think that with "heat soak" playing a role you will be accounting for this more realistically with the MAT in the plenum. I know I'm splitting hairs here but it's what I have noted.

 

[bruce]

Re: Re: MAT sensor location

Originally posted by Ted A.

Bruce, I started putting MAT on my logging dashboard(I am running C-Com DOS) and I noticed ABOUT a 30 F rise running 30psi on a upper 70 degree evening. My second run(minimal cool-down time) ended up with a higher MAT reading (start of logging) but the end of run temp was close to the same(within expectations). I would think that with "heat soak" playing a role you will be accounting for this more realistically with the MAT in the plenum. I know I'm splitting hairs here but it's what I have noted.

I dunno if I'd call it splitting hairs.
The more accurate the info., and data logging the more precise you can be with your tuning.

It can also be an aid in evaluating parts. the more info you have before and after, means you can evaluate what actually changed, and the judge the results. Or after seeing what is really going on how to address things.

For instanance, installing a ram air kit. Does it work becuase there is actually a temp change reflected in the MAT, or is it due to the change in the intake tracts tuned lenght / increased restriction. Does that increase in restriction then from a restrictioin to the max airflow, or just dampen the change so the MAF more accurately tracks the actual airflow.

 

[Otto J]

i would have to believe that having it in hte uppipe closer to the throttle body would be the best place,would there need to be some correction in air fuel ratio, depending on air temp enteringthe motor? being in the airt filter is far from acutl air entering the engine after the intercooler
Otto

 

[bruce]

Originally posted by KLHAMMETT
i would have to believe that having it in hte uppipe closer to the throttle body would be the best place,would there need to be some correction in air fuel ratio, depending on air temp enteringthe motor? being in the airt filter is far from acutl air entering the engine after the intercooler
Otto

But. in the uppipe ignores the heating from the EGR having been on, PCV fumes, their heat, and heating of the air from the manifold it's self.

 

[Otto J]

i am speaking in full throttle calibration terms,so that if the air gets coolder or warmer the ecm compensates