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Caleb lesher SDS EFI RV-7A

Please elaborate

The 60mm and 80mm TBs we supply now have hose barbs tapped into them now for the MAP sensor. This will save people some trouble on connecting the MAP hose. Having it on one runner is really bad, the sensor just receives a sine wave signal from there.

Ross, can you please explain your statement of ?having it on one runner being really bad? a little more in detail?

Thanks,
Mark
 
Mark- the standard practice of connecting a MAP sensor or MP gage to a single cylinder means you get a strong but "lumpy" signal from that one piston hammering up and down. A signal from the TB means that the signal is averaged among 4 or 6 cylinders and is better dampened due to the volume of the common plenum.
 
Did you tap into the plenum or one of the runners? If the plenum, I'd expect there to be no bounce in the MAP due to the large volume and smoothing effect of the multiple cylinders. I tapped into the TB adapter right below the throttle blades and have not seen any bounce in the few engine runs I've done so far. Many mechanical MP instruments have an adjustable restrictor within the inlet fitting itself. Too wide open and you get needle bounce; too restricted and the needle is sluggish or non responsive.

That was my thinking when I put my system together. My fitting is tapped through the back wall of my sump, dead in the middle of the plenum.

Caleb
 
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