I remember awhile ago someone saying the pipe from the inlet manifold to the map sensor had to be a certain length (think it wa something in the region of 280mm)
I've moved my map sensor to a new location and the vaccum pipe for it is now quite abit longer will this have any effect?
Cheers Rich

 

tony mannock once said to me it was important as the pressure drop in the length of pipe was taken into account in the map

steve

 

So if i'm having the car properly mapped it won't matter then?
Cheers Rich

 

i think it has to have a certain amount of perfectly straight pipe coming off the sensor before it bends up to manifold as well mate

 

Anyone else got any thoughts?
Cheers Rich

 

From my limited experience (only put programable efi on four cars and mapped it) i have found it to make absolutly no difference in map pipe lengths. As long as the pipe is all the same bore and is free from restrictions etc it makes no odds. I have only heard it is a problem if, say you are using the ecu on an aircraft or something where the ecu is mounted far from the manifold,where the pressure signal would have a delay while the pressure was building in the line. But for automotive use, where the map pipe is only a few feet then i see no problems. As for being too close, some map sensors (pug gti6 for example) are actualy mounted directly in the manifold.

 

Can't think the length that you'd use on a car will cause any issues, of far more importance is the route, ie it is VITAL that it has a DROP POINT in it prior to getting to the map sensor, ad the drop point should be as close as possible to the map sensor, this needs to be around 4" minimum lower point to ensure that any fuel residue doesn't reach the sensor itself, they are very delicate in this repsect a simple wheatstone bridge affair.
tabetha

 

and water vapour tab

 

My 3 door has the early map bracket is that a problem for me