Hi all

I sold my old Prelude to someone a few months ago - it is a manual JDM Honda Prelude Si-VTEC, BB4 chassis. When I sold it, it had exhaust, a set of 4>2>1 header, a cold air intake (AEM style) and it had a dyno tuned Apexi S-AFC on it.
When I sold it, it was doing 189hp @ wheels / 141.2kW @ wheels with tuning...

Just after I sold it, the car was stolen from the new owner - and recovered 2 weeks later without the cold air intake and the S-AFC. The new owner bought a new cold air intake, also AEM style - and an Apexi V-AFC. He also got the standard flexi joint removed and replaced it with a 2.5" one, with the hope for a little bit more flow.

The below dyno run was done this weekend with the new V-AFC with the VTEC changeover set to 4500rpm, which is the only change in tuning from the run it is overlapped with - which was with I/H/E without dyno tuning. As you should notice, aside from the stronger power where VTEC x-over has been adjusted, the power drops off dramatically on top end now - only achieving 166fwhp/124.1fwkW.

BTW, the new owner highlighted the torque and power lines for some unknown reason, and where the old hp line intersects the new one at 6000rpm he got confused and followed the wrong lines. The old power curve is the one that carries on a lot futher

Does anyone have any theories as to how you could lose about 23whp in the same car, same dyno, with pretty much the same mods? Other cars that ran on the dyno that day all had consistant with previous effort runs..

[URL] http://202.0.54.253/gallery/Dyno-Day...ull=1[/URL]