FE-FC Holden Discussion Forum

Technical Board => Modification Help => Topic started by: Ed on February 18, 2004, 10:09:58 PM



Title: Almost O/T: MAT sensor fitting?
Post by: Ed on February 18, 2004, 10:09:58 PM
Hello,

I am trying to figure out how/where to mount my MAT (Manifold Air Temp) sensor on a Harrop dual plane manifold.

the std Holden V8 (bunch of bananas) EFI has the MAT located in intake manifold runner 6.

The Harrop manifold doesnt have  any holes in the runners besides the one to screw in the vacuum tube.  (Probably because most ppl use Quaddies on these.)

I have thought about.
a) getting a threaded bung welded in the intake runner and screwing it in (worried about potential turbulence tho - not very keen on this idea)

b) getting a carb spacer, drilling it out and mounting it there. (not too difficult)

c) just placing it in the air cleaner (hmmm im worried of this is accurate enough)

d) trying to piggy back it off the vacuum port.

Any one have any ideas on this???

I know its not classically FE/FC related but I know there are some EFI conversions out there.

Cheers

Ed



Title: Re: Almost O/T: MAT sensor fitting?
Post by: fastjbav6 on February 21, 2004, 03:26:12 PM
The Toyota's have the MAT sensor in the air cleaner box after the filter. They must be doing something right because their EFI system rarely fails from what i have experienced.
If  its fitted to the manifold i would think it could be subject to damage from engine backfire (being closer to the flame front), or contaminated by fuel and or oil .
If the MAT sensor is originally fitted to the manifold intake runner i would do the same to the new manifold.
What set up have you got ? I can check up on some tech manuals.

Regards Seb


Title: Re: Almost O/T: MAT sensor fitting?
Post by: Ed on February 23, 2004, 09:38:41 PM
Hey Seb,

Im using a "Harrop" dual plane manifold, with EFI Hardware, 4bbl throttle body.

I will check out the OEM fit ups for cars running the Delco 808 EFI.

I am leaning toward shoving it thru the base of the air cleaner as this will measure air intake to the manifold, rather than air within the manifold.

After a little reading i found out the MAT should read ambient air temp if the motor is at rest and not operating.


Cheers

Ed



Title: Re: Almost O/T: MAT sensor fitting?
Post by: fastjbav6 on February 24, 2004, 04:04:11 PM
I think you should fit it to the manifold so it's measuring air temp b4 the intake valve opens so you get the right amount of fuel delivered (injector duty cycle)

Seb