pmptx

I emailed them to you, since I don't have a way to post them.

They are labled first with the exhaust used then the tune used.

Gernby

Peter's dynojet files are attached below. After looking at all of them, and checking out the AFR's, I'm kicking myself for not sending him different FlashPro calibrations for the dyno test. I tuned his car last Spring with the stock exhaust, then tuned it again after installing the Gern Pipe. My tuning methodology differs from most, and isn't entirely focussed on maximum power at full throttle at every RPM. Since the stock S2000 ECU maps fuel and ignition by manifold pressure alone (MAP), and not by throttle position, it's very common for the engine to run very rich at low RPMs with less than 50% throttle (resulting in poor fuel economy). For that reason, I do my tunes to give a balance between fuel economy and power at lower RPMs, and shifts away from fuel economy to max power as RPMs rise. As you can see in the "tuned" plots, the AFRs start at around 14:1 at low RPMs and gets richer from there. This results in a slight reduction in power in the lower RPMs, even below the stock tune. If I would have thought about it, I would have sent Peter revised tunes for the stock exhaust AND Gern Pipe to have an AFR optimized for peak power at all RPMs.

I don't know what was going on with the dip in power in the stock 5-7 files. There is a weird dip in power that didn't occur in file 4...

I'm glad to see the dyno plot from the stock exhaust with the Gern Pipe tune (#11), since that shows the massive difference in scavenging between the OEM cat and OEM resonator compared to the Gern Pipe.

I'll post some graphs that I find particularly interesting shortly.

Gernby

Below are ALL of Peter's dyno plots, separated by scenario. Each plot uses the same manual scaling, which gives better emphasis on the torque curve.

Gern Pipe with OEM Mufflers and Gern Tune:


Gern Pipe with OEM Mufflers and Stock Tune:


Stock Exhaust with Stock Tune:


Stock Exhaust with Gern Tune: (NOT very happy about this one!)


Stock Exhaust with adjusted tune:


Stock Exhaust with the Same tune used with the Gern Pipe: (I love this one!)

Nicks2ki

Great gains, do you think a top proven header would benefit your exhaust even more? ...(Hytech, J's) p.s cant wait to see more tests!

Gernby

Thanks. I don't believe a header would improve performance after VTEC, but it might improve performance below VTEC. First of all, I believe the OEM header is great already, but second, I think my midpipe scavenges even more than is beneficial when combined with a larger diameter muffler.

Redline S2K

How do you think this would perform on other engines, say kseries or even non Honda motors?

Gernby

I believe the results will be similar on any motor that has (or can have) overlap between the intake and exhaust valve timing.

spectacle

Gernby - just a suggestion. Change the thread title to something relevant to the post!

Croc

it's a good one - took me few thread pages untill i've entered it for the first time

Gernby

LOL ... I agree the thread title isn't very telling, but that was intentional when I created it. I wasn't a sponsor yet, so I didn't want to make it too obvious that I was posting about a new product. Now that the thread has turned into more of a journal about the development of the final production design, I figured I would just leave it alone. I may change the title of this thread, but I will defintiely start a new thread with all everything consolidated in at the beginning once I'm ready to start taking orders.