[RiftsWRX]

Originally Posted by WolfPlayer

So today my dynamic advance multiplier went down to 0.68 . This is the first time my Advance Multiplier has ever decreased from 1.0. Of course, this is in part due to what I did and you guys probably won't ever see this. I expanded my rough correction range such that knock events in the higher RPMs will also decrease the DAM Yea, I'm conservative as all heck . Stock, the DAM is only adjusted up to 5800. I expanded mine out to almost 7000. Today I saw ignition advance at a mere 13.5 degrees at 5800rpms. 13.5 degrees. I was trying to run 15d. Geezus. I am currently tuning my 5000rpm area for only 13 degrees to keep this as safe as possible .... until I can order up some Torco Accelerator to run all the time. I'll also be lowering the boost a tad too. FWIW, EGTs were only 1600d and AFRs were 10.5:1.

As far as the suggestion of using a base map with the intial DAM set lower. Yes, in fact, after Jorge's post/discussion on this subject I immediately lowered my initial value down to 0.8 to test things out. It's been that way ever since.

t

This is going to sound crazy.... but lean out the mixture.... you're probobly running SO rich with such small timing values, that you're misfiring; and the ECU is reading that as detonation.

EDIT: Oh yeah, check your PM's

[WolfPlayer]

Originally Posted by RiftsWRX

This is going to sound crazy.... but lean out the mixture.... you're probobly running SO rich with such small timing values, that you're misfiring; and the ECU is reading that as detonation.

EDIT: Oh yeah, check your PM's

Thanks Jorge.

1) I am currently running 11:1 AFRs (the 10.5:1 was another test that didn't work). The 11:1 AFRs should be fine (IMHO).
2) Replied to your PM regarding interpolation - but, it is a non-issue given that I put the same value across the points for testing purposes.

t

[RiftsWRX]

Originally Posted by WolfPlayer

Thanks Jorge.

1) I am currently running 11:1 AFRs (the 10.5:1 was another test that didn't work). The 11:1 AFRs should be fine (IMHO).
2) Replied to your PM regarding interpolation - but, it is a non-issue given that I put the same value across the points for testing purposes.

t

11:1...

So damn rich... heh

[TheMadScientist]

Originally Posted by RiftsWRX

11:1...

So damn rich... heh

"Dude you can't run any leaner the car will melt"

TMS

[WolfPlayer]

Yea, call me crazy for running 11:1 AFRs

I think people expect my car to be crazy fast or something. I don't think it is. I do, however, believe my tune to be safe. I'm not trying to create butt-loads of power. I have no desire to milk this car for all it has. I am willing to leave 15whp on the table for something safer. Furthermore, I have no need for some rediculous torque number because in an all out drag race I will basically never be at 2800-3400rpms anyhow. Thus, I don't run 20+ psi to get a nice torque number because I think it's sorta 'padding the power'.

FWIW, my MAF volts are very healthy (not that THAT means a damn thing).

I just can't get over running 18psi with 12.x:1. Yea, it tapers in the upper RPMs so you can try to lean it out a bit there. But, the way I am look at it is that the stock ECU runs rediclously rich. I have already leaned it out by ~1.3 AFR points (and more). It's already buttloads leaner than stock. It might not be lean enough to make the best power, but it is lean enough to make good power (IMHO) -- and, as stated before, I have no desire to make buttloads of power. I'm ok with 290whp. I don't need 305-310whp. C'mon, let's get real anyhow. 15whp is nothing (IMHO). I GLADLY give up 15whp+ for a tune that I believe to be safer. But, then again, I come from the V8 crowd where I added ~200whp to my camaro on the stock block and did not use forced induction or nitrous.

t

[RiftsWRX]

Originally Posted by WolfPlayer

Yea, call me crazy for running 11:1 AFRs

I think people expect my car to be crazy fast or something. I don't think it is. I do, however, believe my tune to be safe. I'm not trying to create butt-loads of power. I have no desire to milk this car for all it has. I am willing to leave 15whp on the table for something safer. Furthermore, I have no need for some rediculous torque number because in an all out drag race I will basically never be at 2800-3400rpms anyhow. Thus, I don't run 20+ psi to get a nice torque number because I think it's sorta 'padding the power'.

FWIW, my MAF volts are very healthy (not that THAT means a damn thing).

I just can't get over running 18psi with 12.x:1. Yea, it tapers in the upper RPMs so you can try to lean it out a bit there. But, the way I am look at it is that the stock ECU runs rediclously rich. I have already leaned it out by ~1.3 AFR points (and more). It's already buttloads leaner than stock. It might not be lean enough to make the best power, but it is lean enough to make good power (IMHO) -- and, as stated before, I have no desire to make buttloads of power. I'm ok with 290whp. I don't need 305-310whp. C'mon, let's get real anyhow. 15whp is nothing (IMHO). I GLADLY give up 15whp+ for a tune that I believe to be safer. But, then again, I come from the V8 crowd where I added ~200whp to my camaro on the stock block and did not use forced induction or nitrous.

t

IMO, 11:1 is more dangerous then 12:1.

OK, well not more dangerous, I'm just being melodramatic.

[WolfPlayer]

Originally Posted by RiftsWRX

IMO, 11:1 is more dangerous then 12:1.

OK, well not more dangerous, I'm just being melodramatic.

Wow. Honestly, I never thought I would hear anyone say that 12:1 was less dangerous than 11:1 with 18psi on pump gas. That's NOT a crack. It's me opening my eyes and my mind to other ideas. In your opinion, why do you believe it to be safer? I have always been a fan of less fuel and less timing as opposed to more fuel and more timing. It's just that on a motor making 18psi ... just seems scary to me since, it seems to me, the tune might have the possibility to have less flexibility in a situation that the tuner could not have predicted.

t

[RainMaker]

I can get better power and less detonation and lower EGTs with 11.5:1 than 12.0:1 and less timing.
Why would I go up there with stock pistons without WI?

I'm with Tim... it seems counterintuitive.

[RiftsWRX]

Less pumping loss, better resistance to misfire due to less cylinder pressure (igniting a rapidly expanding gas, vs. something that has so much volume, that it's still a liquid...), improved VE due to charge velocity, smoother delivery of power due to not trying to maximize cylinder pressure, etc.

That being said, here's my take on it.

Increasing VE, decreasing pumping losses, naturally increases flow, by increasing flow you're increased power output. Because, what is a motor? Nothing more then an air pump, and the easier air goes in and out, the more power was made in the same period of time.

That being said, I'm a fond advocate of the school that believes that ignition timing is nothing more then a crutch for poor VE. The better VE and combustability you have, the less timing you need. This isn't an assumption, it's fact. Look at a superior volumetric platform like the 4G63. 3-4 degrees of timing in the midrange? 12-13 degrees in the upper rev-band? And they get away with running silly AFR's like 12:1 with no issues.

Proper combustion chamber design which promotes better VE.

Same idea, different motor. I'm just trying to tailor the environment to achieve as close to the same results with the hardware given to me.

So far, it's working...

[WolfPlayer]

The 4G63 is a totally different animal. That puppy was designed for turbocharging with big boost and the heads support this design. The 4G63 heads are designed for decreased detonation. Beautiful.

My worry with the Scooby is that it is well documented that the USDM intake manifolds do flow more air on cylinder #4. Replacing this intake manifold with the JDM v8 will cure this. However, that doesn't change the fact that I have a USDM intake manifold with flow inconsistencies. There's a reason that many people crack the #4. The intake manifold design coupled with the unequal length headers that create back pressure lead to cylinders that run totally different and have different requirements. Couple THAT with the fuel rail design and things get crazy scary. The 4G63 is not like this at all.

I totally agree with the theory Jorge I think it is spot on. This is the same rationale I used when tuning my Camaro. I guess I'm just a wuss when it comes to my scooby Yea, I'm a wuss.

t

[RiftsWRX]

Originally Posted by WolfPlayer

The 4G63 is a totally different animal. That puppy was designed for turbocharging with big boost and the heads support this design. The 4G63 heads are designed for decreased detonation. Beautiful.

My worry with the Scooby is that it is well documented that the USDM intake manifolds do flow more air on cylinder #4. Replacing this intake manifold with the JDM v8 will cure this. However, that doesn't change the fact that I have a USDM intake manifold with flow inconsistencies. There's a reason that many people crack the #4. The intake manifold design coupled with the unequal length headers that create back pressure lead to cylinders that run totally different and have different requirements. Couple THAT with the fuel rail design and things get crazy scary. The 4G63 is not like this at all.

I totally agree with the theory Jorge I think it is spot on. This is the same rationale I used when tuning my Camaro. I guess I'm just a wuss when it comes to my scooby Yea, I'm a wuss.

t

OK, but consider this. My counter arguement is that Subaru put the knock sensor over #4 for a reason. They considered it the lowest common denominator, so using your same logic, why not do the same.

We do our due diligence to monitor EGT from locations around #4, have knock sensativity based around #4, etc.

So if the car is consistent and doesn't knock; EGT is healthy, etc. Why not trust in the tools that say the car is running properly... at 12:1?

[WolfPlayer]

Originally Posted by RiftsWRX

OK, but consider this. My counter arguement is that Subaru put the knock sensor over #4 for a reason. They considered it the lowest common denominator, so using your same logic, why not do the same.

We do our due diligence to monitor EGT from locations around #4, have knock sensativity based around #4, etc.

So if the car is consistent and doesn't knock; EGT is healthy, etc. Why not trust in the tools that say the car is running properly... at 12:1?

Very good points. Why not trust in the tools? Well, first, I am a wuss Second, Subaru is running their cars OEM with AFRs that are 2+ pts AFR richer with timing maps subject to expand to some crazy timing. <--- That sentence really means nothing, but somehow when I think about it, something in my head rings concerning why they did this (besides the generic excuse of having to deal with so many different regions, conditions, etc). Third, why not go to 13:1 and run even less timing (13:1-13.5:1 = great power on a naturally aspirated car).

I think that most of this centers around the use of the car. 12:1 doesn't have as much fuel around for cooling as the 11:1 mixture (notice that I didn't say detonation prevention). One of the keys to this would be how a 12:1 car handles itself in a situation where it is beat upon on a road course. I have a feeling that you are going to say that it handles itself just fine.

I think when it comes down to it, I'm just a wuss for not going that lean right now. Who knows, knowing me I am sure I will try it one day because, as I said previously, I am a fan of less fuel and less timing. It's just that the 11:1 seems to work so darn well and be so versatile (and yes, that does NOT mean that it is the best choice ).

t

[WolfPlayer]

By the way. I am loving this conversation

[RiftsWRX]

P.S.

...and yes.... our road race shop car has run 12:1 on 93, and 12.5:1 on 100 octane for the last two seasons. It's an '04 even....

I figured it would have blown up by now, so, we put in a 30R kit and turned it up to 450WHP to see if we can blow it up now.

[RiftsWRX]

Oh yeah.... before I forget...

P.P.S. I tuned a car last night at 13.7:1 in the midrange, 12:1 by redline (8k rpm). Was a v. VII RA-C.

Did almost 400WHP on a HKS 2540 at 24 PSI.

BTW, that car has run on that tune for over a year, and we just retuned it using TurboXS's new speed density software.

So yes, it does make more power.