Ignition drop at ~4500 RPM in 6 gear (JDL header + OFT Stage 2)

[Zamor86]

Hey Everyone! (some of you might have seen this already on the OFT FB Group)

My car: 2013 Toyota GT86, manual, K&N drop-in, Mishimoto intake tube (with factory airbox), JDL catted UEL header, HKS Spec-L catback, OFT Stage 2 Tune (Stg-2-v4.03-LC-FSS-Z), running on premium fuel only (it’s “98 octane” here in Europe)

Issue: Experiencing temporarily reduced power at around 4500 RPM in 6 gear after installing the JDL header. No CEL, no codes, no other issues.

I did some data logging with my OFT tablet. Two pulls in 6 gear, one in 5 gear, and a 2000 RPM to redline in 3 gear:

[6 gear - pull 1]:
https://datazap.me/u/raven86/6-gear-...10-11-12-13-14

[6 gear - pull 2]:
https://datazap.me/u/raven86/6-gear-...10-11-12-13-14

[5 gear]:
https://datazap.me/u/raven86/5-gear-...10-11-12-13-14

[3 gear - 2K to redline]:
https://datazap.me/u/raven86/3-gear-...10-11-12-13-14

As you can see, the problem seems to appear only in 6 gear and it seems like what I'm feeling is a one second drop in Ignition Adv. (27 to 18).

The Advance Multiplier stays at 1 and FLKC is 0... I did two runs full throttle on 6th gear and the first time it happened at around 4400 RPM, the second time it was around 4200 RPM. Didn't happen at all with the 5th gear.

I experience no other issues when daily driving or tracking. When accelerating hard from standstill (or in lower gears in general), the car pulls beautifully and smoothly to the redline in every gear.

When I first noticed this:

- stock header = no issue
- stock header + Stage 1 OFT tune = no issue
- JDL catted UEL + still on Stage 1 OFT tune (briefly, right after installing the header) = started happening
- JDL catted UEL + Stage 2 OFT tune = still happening

So it seems like something happened after I installed the header.

Any ideas what it could be? Any additional parameters I should log maybe? Would also appreciate your opinion on the general behaviour of the engine with this setup. Anything I should be concerned about apart from that weird Ignition drop?

Thank you guys!

[tomm.brz]

open the tune with romraider
open vvt intake tables
change values that are 40, to 39

[AussieBRZ]

Either some strange settings in tune tables


Or maybe it's dropping into low power mode running Ignition vvt off (base timeinig A) table instead of ignition vvt on ( base timing B table )


This may be due to a cam error caused by the vvt system being used to it's limit


Do as tommbrz says and take a degree or two out of the max values in cam tables

[Zamor86]

Thanks a lot you guys! I'll try to go with your suggestions and report back!