Versa fuel pressure target and VVT question

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I have been searching and trying to absorb all the shared knowledge, but i havent seen many people talk about this topic. I was following thread where someone made over 400whp on stock fuel pushing IDC to 120%. Looking at their logs, its only showing 11 or 12 degrees of timing advance, this just blows my mind.

I am at 100% injector duty at 360whp (virtual dyno) Ive seen some as high as 390 on a cool night (107%idc logged) His log shows commanded 1700PSI fuel pressure, my versa tune shows 1670 commanded. Is there any room to eek out some there or does that cause other issues with relief valve?

Also, I have read running rich helps spool and running lean helps spool. Personally not a fan of rolling coal so i am targeting .85 at spool up. .77 wide open over 4k. I added some VVT at 3500 but didnt feel any difference.... some people zero it out over 5k, why would that help?

Edit: Last question. What is ideal peak load rpm? Thinking about power under the curve, i decided to make 4000rpm peak and tapper down to redline. I usually hit 100% IDC by 4300rpm or so. I hit 26psi and taper down to 21 or so at 6300. With that said i have what seems to be a little spark blowout during spool up. new NGK plugs, one stepped colder gapped to .028. It didnt have this behavior at lower boost levels so i was thinking about moving my peak load to 4500 or 5000

I have built engine, BNR S4, ported heads, supertech valve springs and gasket match port manifolds. car feels slightly slower then my other completely stock motor with same exhaust, intake, turbo.

 

[Enki]

Last post is probably most important but it's a short thread so might as well read all of it:

https://mazdaspeeds.org/index.php?threads/the-disi-mzr-fuel-system-warning-science-heavy.648/

TLDR: Don't run triple digit IDCs if you want longevity.

Also someone went a bit further than 120% IDCs, plus the stock HPFP can outflow the injectors above ~7k rpm IIRC.
https://mazdaspeeds.org/index.php?threads/500whp-no-aux.1102/

Yeah especially don't do this.

As a side note, peak load generally happens at peak torque which will naturally be where the engine is most efficient. Yeah, you can fudge it with boost, timing, etc but following the natural curve (or designing the engine/cam profile for the curve you want) is usually best.

 

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It still baffles me that you can reach 500whp on 93 octane and i cant reach 400 on E30 with a lot more timing headroom. Is there any reason to zero out VVT after spool up? ive seen it in a few logs but dont know what the purpose is.

 

[Enki]

VVT only impacts the intake cam on this engine, so you don't really *need* VVT post spoolup. Having some present increases dynamic compression and lower RPM airflow (helps spool) but can cost power depending on the cam profile.

 

[buttons]

VVT only impacts the intake cam on this engine, so you don't really *need* VVT post spoolup. Having some present increases dynamic compression and lower RPM airflow (helps spool) but can cost power depending on the cam profile.

oh, so people zero it out if they have aftermarket cams?

 

[Enki]

Depends on piston and cam specs. Sometimes you have to or the pistons buttfuck the valves. I have a custom grind and didn't get any benefit from running VVT past spool.