moonie223

Hello!

I'm helping a friend with a J35A4 with a M90 in the back of an old mini, from about two hours away. There's a track night next Thursday, and there's things that need lined out! I'm pretty decent tuning miatas on megasquirt, have a vague idea where MBT is and where the torque curve sits. Not this one though, I don't know anything Honda!

First, is this a standard VTEC engine, variable profile and lift? Not just phasing, but potentially a simple switch at a certain RPM to an oil solenoid? He doesn't think VTEC is working, these are the dyno plots, looks to be lacking top end torque to me as well. Although, if VTEC was working I guess it's just possible the M90 can't keep up. If the crank pulley is 6.75 as I've measured, it's turning 13500 at 6K RPM which is pretty high for M90's. If you had to guess, off the limited info provided, does it look like VTEC is working?




The red plot is NA, the green plot is 3.8", and the blue is 3.0" and a beefy air to water intercooler. I still haven't managed to take a look at the tune, any good starting points for timing tables? Not sure I'll have time to figure them up myself with det cans in time. Also, it's possible to go past MBT tuning a miata with no det, I wouldn't think so with a roots blower, but is it something you Honda guys see often?

Here's what it's looking like now




Thanks in advance for any and all advise!