205 Vacuum source aftermarket ECU

N

neilc

Member
VIP Paid Subscriber
Fellow Frogger
Joined
Jul 28, 2014
Messages
237
Location
Sunshine Coast
I was wondering what other users had used for a vacuum source for an aftermarket ecu on a standard XU9 engine. Thanks
 
just take it off the inlet manifold somewhere, use a t piece?
 
If I put a t piece on brake booster line, that would be most convenient. Would it have any impact on brakes or affect ecu when brakes are applied?
 
Sounds more like impossible the brake booster hose is much bigger than the ECU vacuum hose. What's wrong with a T-piece on the distributor hose, this is a straight vacuum pick up from the manifold I'm pretty sure.
 
I initially tried to use the distributor line but it is on the air filter side of the throttle body, what is required is a “full vacuum source” which needs to be on the engine side of the throttle body. I have come up with a t piece with a 6mm take off I can use on the brake servo line.
I will test tomorrow
 
neilc said:
I initially tried to use the distributor line but it is on the air filter side of the throttle body, what is required is a “full vacuum source” which needs to be on the engine side of the throttle body. I have come up with a t piece with a 6mm take off I can use on the brake servo line.
I will test tomorrow
Click to expand...
How does dizzy vacuum advance work if it is on the air filter side?
 
Not sure with the 205, but vacuum advance is usually 0 at closed throttle (retarded timing puts out hot exhaust which helps burn away the rich idle mixture). The vacuum comes from just on the air filter side of the closed butterfly. When the butterfly starts to open the port has full manifold vacuum. If it's that way on the 205, it's not a good choice for ECU feed. There are going to be better feeds at brake booster and fuel pressure regulator but surely there are others (505 had its silly econo-meter and heater controls).

Have fun,

Rob.
 
There is the vacuum feed for the SAD which at the bottom of the inlet manifold, my thinking was that it would pick up a lot of “crud” which in the long term could block the vacuum line to ecu. I note that vacuum lines to brakes and fuel pressure regulator are on the top of inlet manifold
 
in principal, I always left the brake system alone when modifying.
 
You must log in or register to reply here.
Top