RomRaider

Has anyone else noticed that its harder to push more air (g/s) when running higher timing. So I guess this a balance of sorts, what is everyone's preferred method of tuning?

I guess these are the high level categories...

1. Low advance, lots of boost, higher load, lots of fuel

For example, I run 232 g/s at redline & 13 degrees timing max load ~5.30, 18.5psi @ 3500 rpms.

2. high advance, moderate boost in lower rpms, higher boost in the midrange, lower load, and slightly more lean conditions.

Here, I run 220 g/s at redline & 18 degrees timing max load ~5.0, 18.5 psi ~4000 rpms

I have tried both, and my butt dyno really likes #2, what is everyone's preference on the stock turbo/block/fuel setup?

Thats pushing a lot of air (considering if all values for Injector Scaling/MAF is STOCK). Remember if you change any of that you're not "really" flowing 232'ish anymore and your load really isn't 5.x.

On 91 octane I can get away with 12-14 degrees of timing at full load up to 4000rpm. Couple that with a clean A/F and it's about all you'll need. If you add more timing you may run into higher EGT's, but overall you're just trying to burn the mixture at the appropriate time and temperature. Watch your EGT's and keep them under 1550 in the mid and 1650 by redline. You don't need to run a butload of timing to make optimum power.

Both runs were made with stock MAF scale with 430 injector scalling... I ran them on the same day for comparisson and baselines. temp ranged from 68-73 degrees. However the lesser g/s was made closer to 68 degrees so I know I definatly wasnt flowing as much air, but I had a hard time looking anywhere since my ass was glued to my seat lol.

232g/s at redline?!?

What kind of boost numbers are you running there? Also, I'd have to think that you would be in the 99% IDC range.

Specs on your engine mods? That is friggin' awesome!

<--- runs 18psi in midrange (tapers to mid 13s @ redline) and has never seen loads > 4.7 or MAF > 206g/s. Perhaps I need to ditch the STi muffler on my catless stealthback for a real one, lol.

Put a panel filter in, you should be seeing 215-220g/s in moderate weather at that boost. With a proper tune you'll be seeing 5.0g @ 17psi.

Like the K&N one? Perhaps I'll have to experiment with this. I've always been in the camp to favor better filtration over more flow, as I like to rallycross and fool around on gravel roads. Perhaps I can run the K&N on the street and the stock panel for the dirt.

I also have the intake silencer on my stock airbox. It was off at one point, but I got sick of all the extra racket.

Enough of my car though, as I don't want (or intend) to hijack this thread.

NP man, if you dont like racket you would not like my car, it has an open exhaust and a custom cai mod to the stock panel.

My setup is a little different but stock block.

I like option number 2 as well but silight different.

2. High Advance, steady boost through the entire rev range, mid-high load (tapers toward redline).

For example I run 230 g/s @ redline & 18-19 degrees timing, max load @ 2.75 (32bit ECU = 5.0 in 16bit terms), 18.0psi from 3600rpm ~redline Also I run 12-13 degrees timing at peak torque.

I used to run option 1. with 24 degrees at redline and used to see 272 g/s @ redline and 3.3 max load but super rich. Didn't feel good though!

Butt dyno tells me 2. feels sweet!

Again you don't need extreme timing # to make good power.

At red line, the car uses all the knock correction and I have 35 degrees of timming after 6000rpms at load 1.75.
You think I should reduce it from the base map?

Running richer than you need to will cost you power and just use fuel. You will get better power from running as lean as you can (without causing excessive egts) with a little less boost and a bit more timing. Retarding timing and/or leaning fuel causes egts to rise, and increased boost or timing may cause detonation, so you need to find a balance between them and boost levels whilst staying within the efficiency range of the turbo.

There's no point running really high boost if you are outside the efficiency range because the intake temperatures will rise, resulting in increased chance of detonation and needing more fuel to try and cool things down. Also, you don't want the boost pressure to exceed the exhaust gas back pressure because it will cause some of the exhaust gases to blow back into the cylinder and you will lose power.

If you still have a standard exhaust or part of it then you are limited in how far you can go because of exhaust gas back pressure. If you can reduce this then you may be able to run more ignition or a bit more boost. We are all limited as to how much timing we can run if we use pump fuel.