MSefi.com read only forum (Jan.15,2018)

10kPa drop between 6000 and 7000rpm.



4AGE running MSIIv3.0 2.89, GSXR ITB's and EDIS-4

Engine also doesn't "feel" as strong in the top end as it did with the factory ECU and plenum intake, or the screaming from the ITB's just scares me into shifting.

O2 seems to read happy, I do not hear or feel any missfire or knock.

I could measure this with the MAP sensor on datalogs, or even with the MAP sensor disconnected (and running Alpha-N), calculating horsepower in MegaLogViewer also shows this dip.

Any tips on where I should be looking??

Thanks.

I wonder if it's a standing wave effect of some sort that's not good for the MAP. Trying different length intake trumpets or runners may help.

I cut about 1-1/2" off the trumpets, and ended up with this, a 1.4kPa improvement. To go much shorter, I'd have modify the intake quite a bit. I could try longer.....

No, wait. Found the same 1.4kPa difference in the morning's datalog, using the original trumpets.