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ndamico
04-20-2003, 15:38
Ever since I have installed the banks waste gate actuator I have been getting about 30PSI max boost. This is from my gauge, which monitors the actuator line pressure. Banks sent me a new set of gauges that connect directly to the ottomind. The new boost gauge gets its numbers from the OEM boost sensor, which as far as I can tell is located just before the air enters the engine after the intercooler.

Their boost gauge is consistently 2 psi lower than mine (which I expected) all the way until I hit about 25PSI, when theirs never goes any higher. I

britannic
04-20-2003, 18:59
Do you have the Bank's Ottomind installed and connected to the boost and pyrometer gauges?

ndamico
04-20-2003, 20:38
When i had the second set of gauges hooked up they were connected to the ottomind. thats how i was able to notice the constant 2PSI difference between the two gauges, as well as the larger difference when pressure exceeded ~25 PSI.

CPMac632
04-20-2003, 21:55
What exactly does the ottomind do? I know if the factory boost sensor actually senses too much boost it will set a code and put the engine in limp mode so I would guess they have capped the boost psi signal in the ottomind. Just a guess.

SoCalDMAX
04-20-2003, 23:34
I know someone said that there is some loss of boost from the intercooler (2psi or so) but I've mounted 2 different boost sensors on the same gauge, one on the wastegate hose and one on the intake manifold just before it enters the valley, and they read identically under the same conditions.

Regards, Steve

britannic
04-21-2003, 09:09
My understanding of the Ottomind from Bank's tech support, is that it monitors EGTs and boost pressure and will regulate the amount of fuel injected to keep both parameters within a preset range that yields reliable power without exceeding safe limits.

britannic
04-21-2003, 09:11
Do you have two boost gauges connected simultaneously, one to the Ottomind and the other to a tee or some other connection?

ndamico
04-21-2003, 13:55
SoCalDmax, how much boost have you got (max) with your dual sensors?

britannic- the ottomind monitors EGT's and will de-fuel if egt's reach 1250 degrees. that's the limit. as for the boost gauges, i do have two- one connected directly to the ottomind that reads GM's boost sensor and one connected to the actuator line.

the Dmax will set an overboost code if you exceed 23PSI boost for more than 30 seconds, and the engine RPM is below 2700. i got that info from Alldata's CD.

Banks alters your boost by changing the wastegate actuator. you do get more boost with more fuel, but tweaking the actuator is what seems to make the difference. for example, the juice gives me more fuel, so it yields about 3-4 PSI on my gauge.