hx-35 tunning help

dsmtalontsi95 · 10-29-2009, 07:08 AM

Well Something isn't right. With dsm link I'm showing 55lb/min and everyone says that this can't be right with my 70-90 times being only 1.8. Right now I'm at a loss and don't know what to do. What could be wrong? My boost est is dead on. I know I'm rich but what could this be?

The log is in the holset thread and wont let me post it here.Holset Turbos, PART 6 (post 983)

I could really use a hand with this one.

Rob10_99 · 10-29-2009, 07:18 AM

Sounds like you know your answer. Ok your at 10.9< and then you think its slow? Looks like your making tons of power, whats the issue?
No knock holding you back, this on pump?

dsmtalontsi95 · 10-29-2009, 07:40 AM

yes it's on 93. You think running a little rich is the cause of it being that slow?

dsm-onster · 10-29-2009, 07:50 AM

As I said in the holset 6 thread, Your maf count is really choppy. It's possible that you need to picture a more smooth version of your maf counts to get an accurate assumption of your airflow. I've seen this before with the 3" gm maf. Incidentally at about the same airflow, with my old 60-1.

Wide band is actually showing 10.9 at about 70 and goes down to 10.5 by about 90. Some setups see BIG gains going from mid to high 10s:1 to mid 11s:1. But none of my setups have been too responsive to a/f ratio changes in this range. For my cars, going from stock to about 10.5ish:1 made the most difference.

Torque an HP estimates seam to jive with the airflow. And you're boostest is spot on.

dsmtalontsi95 · 10-29-2009, 08:10 AM

I thought since my boost est was on then my maf should be calibrated. Wont moving thos sliders mess them up?

viperlp01 · 10-29-2009, 08:32 AM

You move the fuel sliders to change the A/f.. YOu are now done touching the mafcomp sliders. They are set right.. I have noticed choppy signal from my gm maf too... Just slowly bring the sliders down until you get some knock then you know where you need to be..

dsmtalontsi95 · 10-29-2009, 09:13 AM

Quote:

Originally Posted by dsm-onster

Your maf count is really choppy. It's possible that you need to picture a more smooth version of your maf counts to get an accurate assumption of your airflow.

I thought he was talking about the mafcomp sliders. dsm-onster what sliders are you talking about?

dsm-onster · 10-29-2009, 09:21 AM

I'm not talking about sliders. I'm talking about your mafraw curve and your airflow curve as logged. You need to smooth them out in your head when you look at them. Picture the average curve between the wiggle of the actual airflow curve. You can picture what your airflow is supposed to look like if the gm maf wern't being so choppy. The average in the curve after the maf starts getting choppy is around 53lb/min.

Still just a guess, though. Seams the gm maf doesn't like much beyond 3000hz VOLUME flow in BLOWTHROUGH. I think you should clamp at 2800 and use a map sensor or go to SD if you can't figure out why the hertz is so choppy. Dropping counts that much can be dangerous at leaner a/f ratios. And could be the reason why you're getting det and have to run richer.

You can try things like swiveling the maf to other varios angles. How is your setup before and after the maf. I've found that longer tapering from the ic piping to and from the gm 3" maf does better. Running 3" piping is best. At least 6" before and after the maf need to be straight. Or run in drawthrough

The gm 3" does so much better in drawthrough. It is more consistant.

Also the 2g timing map is conservative. Especially for the faster pistons speeds of the stroker motor. You could bump timing a little and gain lots of power and leave the a/f ratio alone. Assuming the metering won't bounce around so much. What is your CR?

For reference, in 2g cars with 2.0L motors I target desired boost level then 10.5-11:1 a/f ratio. And then add timing until I see knock. With a 1g car even with 7.8CR, I pull timing to where it looks like a 2g curve and then start with a target boost and the same a/f ratio. Then go in and add timing if I can. You look about where I would put the fuel. So with my humble experience with pumpgas, you cant get a better fuel tune than that. I think you can get a little more with timing, when you stop that hertz count from bouncing like an ADD child on a trampoline

Either way, even at 53lb/min, that is a really good airflow for a bolton turbo with a smaller turbine wheel at only 28psi. You done good

Just need to iron out some of these bugs.

dsmtalontsi95 · 10-29-2009, 10:22 AM

Quote:

Originally Posted by dsm-onster

Also the 2g timing map is conservative. Especially for the faster pistons speeds of the stroker motor. You could bump timing a little and gain lots of power and leave the a/f ratio alone. Assuming the metering won't bounce around so much. What is your CR?

I'm not detonating yet, I'm just working on leaning things out slowly. As for the before and after on the gm, I have 2.5 pipes with 2.5-3.25 couplings to accept the gm. My cr is 8.8. So you think that my maf setup is causing to be so jumpy? If I turn the maf and it levels out do I need to reset my fuel trims?

dsm-onster · 10-29-2009, 10:55 AM

Yes, you may have to go in and recalibrate after you alter the maf position in any way.

I recommend stopping with the fuel tune. Looks good. Add timing, if you dare. I'd clamp the maf at a 2800hz and start adding timing to see if you can get a nice 70-90 time. You don't NEED a map sensor to clamp the maf and it work correctly.

dsmtalontsi95 · 10-29-2009, 02:26 PM

I have never messed with timing. When people say they add timming does that mean they are reducing the number (slider) closer to 0' or farther from 0'

dsm-onster · 10-29-2009, 03:39 PM

Move the sliders UP ^

dsmtalontsi95 · 10-29-2009, 03:49 PM

I have another question. I was just playing around in the maf clamp area and found there is a template for a smim that I never used. Could that hinder some performance that I have a smim with out using that template?

dsm-onster · 10-29-2009, 07:27 PM

That template is for the different VE that your motor will have with a SMIM. Use it. Clamping the maf begins an assumption by ECMLik after that. Based on the airflow at the point of clamp, ECMLink will do estimations for airflow using an assumption of volume flow efficiency.

dsmtalontsi95 · 10-30-2009, 02:06 PM

wow ignore thefirst 3 logs.

I added some timming and It felt better. I also had some on in the car with me and also put in 5 gallons of gas, so it might be a little slower. I never got any knock but I'm not sure how much timming to add safly with 93. Let me know what you think.

dsm-onster · 11-02-2009, 10:29 AM

Not bad, with alot more weight you have about the same 70-90 time. Add timing until you see a little knock. And at the rpms where you see knock pull it back a degree. Keep adding timing at the other rpm points. Be very methodical and do this one degree at a time. once you see 1-2 degrees of retard. is when you want to pull timing back down 1 degree. Just incase you get a bad tank of gas, you won't have such an aggresive tune that you blow things up.