More specifically, I'm comparing the Honda design to that of say, Mitsubishi, for forced induction purposes. For example, on the 4G63 Eclipse engine, air is read by the MAF before the turbo. The air that is released between shifts by the BOV is recirculated in between the MAF and the turbo, and still enters the engine. If this recirculation hose is disconnected, the air is released to the atmosphere, but the ECU doesn't know this. The car therefore runs very rich for a couple seconds, and stalls out if the driver doesn't tap the throttle a little to prevent that.

This applies to both Si's and Non-Si's (and Accords for that matter), as Honda is now using both MAP and MAF sensors to help with emissions control. I'm wondering it these cars are the same as Mitsubishi, or if the MAP has higher priority than the MAF when the ECU is calculating the amount of fuel to inject. I'm assuming the latter, that the ECU calculates a rough value based on the MAP, then fine-tunes it using the readings from the MAF.

For those of you that have an Si with a turbo kit installed, where is the MAF? Before the turbo or after it? If it's after the turbo, is it before or after the BOV?

Just trying to educate myself. Note: If this would be better answered in another forum, like in F/I, let me know. Thanks ahead of time!!

 

I'm curious about this too and thought that the MAF was only added to the new Civics (non Si's) because the MAP sensor reading would be unreliable (as far as metering fuel, right?) since the throttle plate can now open at wide angles during cruise to reduce obstruction of the airflow going into the engine. This is part of the "i" in the R18's i-VTEC moniker.

The K20 in the Si doesn't do this, however, which brings us back to your original question.

 

Based on some pics that I've seen of turbo'd 2006+ Civics, including the R18 and the K20 engines, the BOV still vents to the atmosphere the same as any other Honda. So, I doubt this causes the cars to stall like it would to a MAF-only engine, like the Mitsu's.

The signal from the Civic's MAF is probably only really used when, as you said DaiJekBok, the throttle plate is electronically opened by the ECU to reduce obstruction during cruise.

Here's a pic of the engine of Polk's turbo'd Ex:

 

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wow, thats ****** SICK!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

I thought the same thing when I saw this car, but of course it's based on a car owned by Polk Audio. So the point of the car is to showcase its 1600 watt stereo system, not the performance gains. If you read the article, you'll see it also has 2 Nitrous Express bottles. So, to all of you non-Si haters, the engine does have at least some potential...

http://www.hondatuningmagazine..._ex/

 

ya i really wanna know how Ryan Shutt did that turbo set up

of course we all know it's custom but how is it integrated we def need a write up!