Hondata

I did a search and the closest post that I could find was this: AndyE's problem
Here is my current setup:
'00 Si
stock JRSC
stock b16a
Comptech Icebox
DC 4-2-1 ceramic header
Thermal exhaust
stage 4b
RC 440 injectors

This last Saturday I had a CRV crank pulley installed. That night I tried to datalog a third gear pull. Two things went awry.
First: I got onto the tollway entrance and put the car into third gear @ about 3500 rpms and accelerated. Somewhere around 4000-5000 rpms the engine cut out and I glanced at the boost gauge. It appeared to indicate 12-13psi. I still have the factory map sensor. I immediately let off the throttle and eased up to the toll booth. After going through the booth, I pulled over to check my datalog.
Second:My laptop battery died right before I came to a stop. I forced it to turn on and possibly salvage the recording. So I'm not sure if the recording is accurate.
Here's the kicker: after getting home and plugging the laptop in to use and recharge, I noticed something scary in the datalog. Boost was off the chart at 4550 rpms and the injector duty cycle was only 50%. The highest the map sensor read was 1.725mbar. It's obvious that I need a different map sensor. But has anyone encountered such high boost levels that early in the rpm band?

Thanks.
Alf

BplantCivic wrote:But has anyone encountered such high boost levels that early in the rpm band?

Doug? Derick?

Are you sure you weren't hitting the boost cut? That would cause your injector duty cycle to drop dramatically (although I'd expect it to drop to 0%) if you exceeded the boost cut.

The default boost cut is at 11.2 psi, which is the theoretical maximum that the stock MAP sensor can handle. I have an Endyn stepper pulley that claims 8-10 psi but I regularly see 11-13 psi as well. I've slammed into the boost cut a few times myself; when I get some time I'm going to disable it, since it doesn't make a lot of sense for a fixed-boost application like a supercharger.

The real question is, how does the stock MAP sensor behave (and how does a Hondata ECU interpret this behavior) when the boost rises above 11.2? I'd assume that the MAP voltage levels out at a certain point above 11.2 psi, which wouldn't be a huge deal since the amount of fuel required for 11.2 psi vs. 12-13 psi is pretty much the same (i.e. "lots").

Can you offer up your datalogging session so we can see what it looks like?

-Andy

When I get the chance, I will post what I captured on the datalog. The default boost cut may be 11.2, but according to the datalog it cut out at 10.5(1725mbar). I hope a 3bar sensor will help.