Tuning 18g w/ FMIC

I've slowly been tuning my td06-18g since installing the itsme FMIC. I'm looking for advice on timing, specifically where I should try adding some. Do I add just after peak load, or can I add a little even before that? I run 93 octane.

 

Also I was curious on DW injectors how much of a variance there can be in the ratings. I bought a set of used 740cc, I had my typhoon previously scaled when I was just stage 2. After installing the injectors I had to enter the scaler as 780cc to get my fuel trims back close to 0. The injectors didn't come with flow sheets. Anybody else notice DW injectors that flowed a good bit more than the standard 740 or 850?

 

For AFR I am still scaling my MAF in the higher flow areas. My target from 4000rpm on is 11.07.

romraiderlog_20100416_161241.csv

Timing is very strong already, (good spool too;)) there is definitely more power to had with more timing, if the gas can take it. You are already running a fair bit more timing then I can even run on 94, but I see that all the time on certain brands of US 93.

 

Feel free to try a little more timing, and see what if the ECU is happy with it. if you see knock, then back it off.

 

The only caution I have for you guys with really good gas that can run great timing: be very careful when you fill up with gas that you have not tuned for, like when you go on a road trip. Always do a quick log and look at LV when you change anything.

You also have a bit of boost dip after peak, and then this really weird MAF curve in the 2800 to 3400 range. What intake?

 

FWIW my stock injectors (flow tested and cleaned from DW) did not match my stock scalar (search, I posted the data) but my 750s or 740s where about 730 on the sheets I got from DW.

My intake is a k&n typhoon, I seem to always be working on the scaling. I just made this comparison of how I have mine scaled compared to a few other on this board who have done it.

 

Spool is getting better as I tweak wgdc. When I had a perrin TMIC I could hit 20psi by 3200-3300rpm. So far I have the FMIC at about 3500. When I first put the FMIC on with no adjustments it was about 3700.

Typhoon scaling compared.csv

Looks pretty good to me.

 

Just get the maf scaled in correctly on the high end..it looks like it is bordering on too lean. I too target 11.1 in the high-end maf, but I have seen swings of almost a full point (leaner) during the change of seasons. Make sure you tighten down closer to your target.

 

One thing to also be careful with is your maf scaling during spool up. FMICs usually dip rich for a second before hitting the afr target. I have noticed that if you overcompensate for this on the maf scale, you could dip lean.

My dw740's flow sheet showed 741-742-741-741..I set the scaler for 740 and stock latencys.

Yeah I'll keep working on the MAF scaling. I guess I thought I would be flowing a little more air, I was hoping for 300+ g/s. I also thought I would see more torque, as I'm hitting load of 3.4. When I do an airboy graph its only like 310 ft/lbs.

 

I do have a grimmspeed crosspipe yet to install (and I'll port the stock manifolds at the same time). Not sure how much that will help with flow. And I have an extra set of TGVs that I can delete, sounds like gains are fairly low but it would likely be a final mod.

I am not talking about the MAF scaling, but just look at the MAFv in the spool up range, maybe some surge? Weird?

 

I would try upping the boost to get more then 300 g/s out of it. I would imagine an 18g could get a bit more out of it then a vf series.

 

What I don't understand is how you can flow only 280 g/s, but hit 98% IDC on 740s?

 

FWIW your MAF scaling seems relatively close at 4.58 volts equaling 280 g/s, but how your IDCs are soo high is beyond me. That seems like stock injectors.

I am not talking about the MAF scaling, but just look at the MAFv in the spool up range, maybe some surge? Weird?

 

I would try upping the boost to get more then 300 g/s out of it. I would imagine an 18g could get a bit more out of it then a vf series.

 

What I don't understand is how you can flow only 280 g/s, but hit 98% IDC on 740s?

 

FWIW your MAF scaling seems relatively close at 4.58 volts equaling 280 g/s, but how your IDCs are soo high is beyond me. That seems like stock injectors.

 

I have seen the same weirdness in mafV in some of my logs with both the stock turbo and the vf43...it sorta bounces (along with load) around during spool up. A local guy with the HTA68 has the same issue... I do not see it on yamie's log though?

 

How did you determine his IDCs were maxed? You could tell from the log posted...I do not see IDCs? That does sound like stock injectors, I maxed my stock injectors at around 280 with the stock turbo on really cold days.

How did you determine his IDCs were maxed? You could tell from the log posted...I do not see IDCs? That does sound like stock injectors, I maxed my stock injectors at around 280 with the stock turbo on really cold days.

 

I didn't log IDC, but on prior runs I've seen only like 70% at 290 g/s. Is there a way to calculate IDC aside from directly logging it?

 

I wonder if richening up my AFR could actually benefit some? Maybe I'll try 10.9 just to see if there is any difference.

Ooops. I am in China, and stuff is really hard to download, and even longer to load. I got mixxed up on logs, so disregard most of my comments.

Ooops. I am in China, and stuff is really hard to download, and even longer to load. I got mixxed up on logs, so disregard most of my comments.

 

and no google right?!

I didn't log IDC, but on prior runs I've seen only like 70% at 290 g/s. Is there a way to calculate IDC aside from directly logging it?

 

I wonder if richening up my AFR could actually benefit some? Maybe I'll try 10.9 just to see if there is any difference.

 

You might, but I doubt it will be measurable, I have been thinking of doing the same thing for a little more margin of safety. Before you change the afr target get the maf scale solid.

 

Your IDCs are fine...that is roughly what I get at 290 g/sec with my DW740s (70%).

Don't go too rich though. 11.1 to 10.8 should be fine if you want to be conservative.

I didn't log IDC, but on prior runs I've seen only like 70% at 290 g/s. Is there a way to calculate IDC aside from directly logging it?

 

I wonder if richening up my AFR could actually benefit some? Maybe I'll try 10.9 just to see if there is any difference.

 

Actually the logger itself calculates IDC from RPM and injector pulse width. IMO there's no need to log IDC unless:

a) you've never logged before and you have no idea what it is

b) you've got weird AFR issues you're trying to figure out

c) you've increased MAF significantly since the last time you logged it

Started hearing some type of leak yesterday only under high boost, 19+psi. Its high pitched whistle but not really that loud. I have all my FMIC couplers very tight so I don't think its those, I'll check them again though. When stock BPV leak is there any noise associated with it? I'm wondering if my BPV is leaking only under high boost and that is causing a very slight rich dip in AFR.

Whistle noises often come from pre-turbo exhaust leaks. Not always, but often.

Yeah, I was wondering maybe UP leak, but it seems pretty quiet. I've had the STi UP installed for about 3 years now though an never leaked before. Hopefully tomorrow I'll get some time to just re-tighten things.

 

If stock BPV leaks do they make any noise?

Question for you guys, several times when merging onto freeways I have gently accelerated, say 50-60% throttle at about 10psi, then if I mash the pedal to 100% boost doesn't really rise, just stays about 10-12psi even as the engine revs out to redline. What would cause this? If I do a 3rd gear pull and go 100% at 2000rpm it goes to 22psi tapering to 19 just fine.

What BCS are you running?

Grimmspeed EBCS.

 

It only happens once in a while, so I'm guessing its somehow based on the load cells and wgdc?

I have the same BCS, much quicker and more stable than the stock one.

Question for you guys, several times when merging onto freeways I have gently accelerated, say 50-60% throttle at about 10psi, then if I mash the pedal to 100% boost doesn't really rise, just stays about 10-12psi even as the engine revs out to redline. What would cause this? If I do a 3rd gear pull and go 100% at 2000rpm it goes to 22psi tapering to 19 just fine.

Do you have any logs displaying this activity, it hard to say without data.

Unfortunately no logs, haven't had a chance to log in quite a while. I really need to get out one of these weekends.

Next spring I want to try E85, just not sure if my DW 740s (that actually scale out at 790cc) will be enough.

You can make them work but will be giving up a few psi above 5500ish rpms.