Boost variations.. more boost without BCM?

[MaxPSITalon]

My 2g talon has made 7psi max since i bought it about 2 months ago. i have been reading on the forums that stock it should make around 10 psi. i did a boost leak test... found no substantial leaks. i then removed the BCM and blocked the vacuum lines to it (with a screw) just to see what happens. I got a check engine light of course... but the boost went up to about 10-11 psi. I reinstalled the BCM and the boost is back around 7psi. Why does it make less boost with the BCM installed?? The BCM is modified so there is no restrictor. What is wrong?

 

[Eastwood95]

uhh, maybe the Boost control Solenoid is bad...........try and get another one to plug and play, or buy a new Manual Boost Controller.

 

[MaxPSITalon]

what does the boost control solenoid do? i will try a different one and see what happens (parts car). your right i could just put a MBC on it and set it at 10 psi. any other ideas??

 

[DSMcamaro]

Whats a BCM? I assume your talking about the BCS like stated above.
Sounds like you BCS is working properly.
http://members.shaw.ca/dsm.1000q/Engineprimer/1G/bcs.htm

I would get an aftermarket boost gauge if you don't have one already, throw in a mbc and set it to 12psi.

 

[MaxPSITalon]

i do have i aftermarket boost gauge.... and plan on doing a MBC in the near future. I was not aware that the MBS actually made the car have LESS boost. 7 psi seems a little low but maybe not. thanks for your help.

 

[Eclipse98_RS]

Anywhere around 7.5-8 PSI (7.77 if youre technical)would be around stock for a 2nd gen if you figure about 9 horsepower for every pound of boost you run. Im running 10-11 PSI and i have 240 HP so if that gives you any indications. (210 HP/214 LB FT torque is stock.)

 

[Eastwood95]

uhh, the stock boost level for a 2g is 14psi max, then it should fall of in the higher rpms....
The Boost Control Solenoid is the stock "boost controller". Maybe yours is faulty. 7psi seems pretty low. You should just buy a Manual Boost controller and hook it up.

 

[MrBoxx]

Running a vacuum line straight from the compressor outlet nipple to the wastegate actuator should give you about 10-11 psi. Try running it that way and see what happens. Keep the BCS electrical connector plugged in, even after you get an MBC, to avoid the CEL.

 

[DSMunknown]

i did a boost leak test... found no substantial leaks.

There should be no air leaks whatsoever. But we'll assume that is what you meant.

 

[MaxPSITalon]

Running a vacuum line straight from the compressor outlet nipple to the wastegate actuator should give you about 10-11 psi. Try running it that way and see what happens. Keep the BCS electrical connector plugged in, even after you get an MBC, to avoid the CEL.

I was considering doing that... since i made about 4-5 more psi. (but had a CEL). I just want to make sure that by not having the vacuum line hooked into the BCS that my performance or gas mileage wont suffer. Is it correct that i will not have a CEL as long as the electrical connector is still plugged in?

 

[MrBoxx]

As long as the electrical connector is still attached to the BCS itself, you won't see a CEL. You can cap off the nipples on the BCS or leave them uncapped, your call. Mileage and performance won't suffer at all.