OK, im confused. I know this isn't the topic of the thread, but interesting none the less.

how would that make the boost gauge off then? Are you saying that the turbo puts out different boost levels in different weather and the boost gauge doesn't recognize it?

 

THe sensor reads relative to a total vacuum.. so air pressure at sea level would result in a slightly different reading under boost unless it were recalibrated every time the car were started.

 

Like turning up boost at sea level and turning down boost in the mountains,etc...

 

That description of boost guage operation sounds like the way an altimeter works in an airplane, it needs to be calibrated "set to zero" to the altitude of the airport or dialed in using the currnet pressure.

 

so, you are saying that the boost gauge is off because its not actually at 0 due to atmostpheric pressure.

what im saying is, my boost gauge was spot on with the DD sensor at the dyno....and i haven't changed the boost and the boost gauge doesn't show anything drastically different at peak or redline....nothing like 5 psi like dave is talking about.

again, maybe im still misunderstanding

 

How bout we start another topic for the boost gauge variations? Between that and "subscribing"....geez

 

Well, my questions and posts are 100% on topic.....

your comment however(and mine in this post) are 100% off topic. keep peanut gallery comments to yourself.

 

Your boost gauge is correct. The boost gauge is reading gauge pressure, meaning pressure produced relative to ambient pressure. The AEM sensor is reading absolute pressure, although not exactly. Absolute pressure would be gauge pressure plus ambient pressure, but the AEM sensor is reading gauge pressure minus standard atmospheric pressure. So if ambient pressure is any different than standard atmospheric pressure, the AEM sensor will be off by that amount. With any compressor, what really matters is the pressure ratio across the compressor and the boost gauge is actually showing you that. I feel as though I'm rambling so I'm going to stop here. If anyone has any questions or needs clarification I can try to help.

-Paul

 

damn, good answer. Thanks

 

 

Interesting?

 

keep it up david! since the wr seems not to be going anywhere, hopefully the 20g will make some good power over the tme!

 

Dave-
Great news and can't wait to see what numbers this thing will produce.

 

Great job David, Maybe I should upgrade to one of these from my current setup(cause she only runs 126.4 mph in the quarter)

 

Yay 20g, I've been looking forward to this for a long time... I don't want a big huge turbo, but I'd like a bigger quicker one like the 20g and if that doesn't happen I'll just get a quicker one and get the TME.