Where to put the MAP sensor?

[Davepar]

Van?s includes their $50 manifold pressure sensor kit in the firewall forward kit. The kit is tailored to using their MAP gauge. It seems that most people adapt it to an engine monitor to get the MAP sensor aft of the firewall. However, I was reading on Dynon?s forum that it should be OK to put the MAP sensor on the engine side of the firewall. That would make the install much easier. I was thinking of using the spare port on the oil/fuel pressure manifold. There would be fewer breaks in the MAP pressure line, and one less hole through the firewall. One drawback is that I?ll have to find a custom length flex hose from the cylinder to the manifold. Does anybody see any other drawbacks to this approach?

Dave

[casper]

Originally Posted by Davepar

Van?s includes their $50 manifold pressure sensor kit in the firewall forward kit. The kit is tailored to using their MAP gauge. It seems that most people adapt it to an engine monitor to get the MAP sensor aft of the firewall. However, I was reading on Dynon?s forum that it should be OK to put the MAP sensor on the engine side of the firewall. That would make the install much easier. I was thinking of using the spare port on the oil/fuel pressure manifold. There would be fewer breaks in the MAP pressure line, and one less hole through the firewall. One drawback is that I?ll have to find a custom length flex hose from the cylinder to the manifold. Does anybody see any other drawbacks to this approach?

Dave

Dave, I have a 7A and i put my M/P sensor on the back side of the firewall, I don't think the little black box, plastic, would stand up on the front side of the firewall, I noticed that you are going to run a couple of P-Mags. You will have to plumb them in to your M/P line. I should get my E/Mag and P/Mag this month. and I will have to cut into my M/P line
Doyle Reed RV7A O-360 Superior 427hrs

[Kahuna]

Originally Posted by casper

Dave I don't think the little black box, plastic, would stand up on the front side of the firewall,

It will absolutely hold up on the fwd firewall.

Cleaner and easier to plumb there.

[Sam Buchanan]

Dave I don't think the little black box, plastic, would stand up on the front side of the firewall,

If the Vans MAP sensor is anything like the NAPA sensor used with the Rocky Mtn uMonitor, it will survive just fine forward of the firewall. Look at the second photo on this page to see the MAP installation on my RV-6 which has worked perfectly for the past six years (~700hrs):

http://home.hiwaay.net/~sbuc/journal/engine2.html

A stainless flex hose is clamped to the barb on the sensor and the other end is attached with an AN fitting to an AN/NPT fitting in the clylinder.

Sam Buchanan

[Davepar]

Thanks guys. I don't have the sensor in hand yet, but it sounds like forward of the firewall should work fine and will probably be easier.

Doyle- you're right about the P-mags. I don't know what fitting is on the P-mag, so I'm not sure how I will plumb them. I might use a separate 4-port manifold from Spruce. http://www.aircraftspruce.com/catalo...anifoldfit.php

I'm supposed to get my P-mags this month as well. We must be in the same manufacturing batch. I hope they arrive soon. I want to get them installed and my engine mounted over the holiday break.

Dave