For the people that have done the swap to the mini-ram, where did you mount your map sensor to and is having a longer vacuum hose connected affect the performance that you can see?

 

I mounted on firewall back of intake.
I've always been told to mount a little higher that vacuum source.
Don't know if wive's tale or not, but makes sense.
My hose is about 10" long on the 58 vette, and about 12" long on the 67 Firebird conv.

 

General theory is to mount as close as poss to vac source for best response and not share vac line with anything else like AFPR

 

Yeah, when I first put the TPI in 67 bird, I had to mount map on firewall because of older plenum, I had one less vacuum source, and shared map with ac. Never did right till I took off plenum and drilled another vacuum hole for standalone map. Due to using taller valvecovers, I couldn't mount map on plenum, cause I had to jack up coil also.

 

It is very important to not share the vacuum source for the MAP with anything else. Having the MAP sensor higher than the vacuum source will allow any condensed liquids to drain back to the intake. Most Megasquirt installs have the MAP installed on the controller in the passenger compartment, with runs of 3 to 4 feet not being a problem. The signal travels at the speed of sound so there won't be much of a difference between 1 foot and 4 feet although, unlike at least one other thing that comes to mind, shorter is better.

 

I mounted it approx. where it sits on the stock intake

 

thanks for the replies guys. i like the idea the last post had with mounting approx. in the same spot. i'm an idiot and can't believe i didn't think of that .