Rolling Dyno SPT vs Factory

[Prime Power]

I think it has more in the midrange. I really appreciate the info. When I get some time I will go log those, and post them. Does it need to be both WOT and cruise or just WOT. Thanks.

[sirsimon]

You guys are making me re-think intake mods. I had pretty much ruled them out until I read this thread.

[TSiWRX]

I am not reading the knock sensor I am using the Knock Correction to read the amount of advance or retard the ECU is being given. Thanks

 

^ Cool beans. Just wanted to make sure.

 

I tried capturing the knock sensor digital output, running only that and engine-speed, and could not get a reliable enough reading, and was given this same advice.

 

The moment that your KC becomes in the negatives indicates your running lean.

 

Not necessarily - there could be other reasons why knock correction could be going negative. What you'd really need to figure this out, definitively, would be an *integrated* wide-band O2, run with the datalogs.

 

I think from most of what I have read about the SPT intake indicates it should run slightly rich from the porting or baffling used in the intake by where the MAF goes?

 

^ Unknown - the testing done by Cobb would suggest otherwise. I'm not certain, due to my absence, if SoA/SPT ever provided a valid contradiction to Cobb's claims, though......

[Prime Power]

Well I did a run, can't do my knock sensor on my software but here is what I got. Don't know exactly what I am looking for. My temps were up today, but as you can see, it is much hotter outside. Not going to switch back to stock to compare as that one day was good enough for me. Well, here you go.

[Faster_nu]

I would be great to catch enough data from everyone that we could compare what various modifications work the best.

 

Prime - have you tried ECUExplorer with your data cable? Or I have a source for a 20.00 cable that will work with ECUExplorer if your interested.

[Faster_nu]

Humm just noticed that yours is the XT outback, mine is a GT legacy. Do you have the 5eat? or the 4eat?

[Prime Power]

I have the 5EAt. I will have to download it and try it. Don't see why it wouldn't work, just a cable. Also good to compare apples to apples. However I am pleased with my software, as it is a code reader and will also clear them. Along with the speedtracer software is nice.

[friviz68]

how do you do the ecu quick lern?? i also have to spt intake and my car dosent idle very good with this intake system on my car.

[Prime Power]

Just disconnect the battery for say about 5 minutes, then reconnect. I didn't have the trouble. Could be you need to do that.

[Faster_nu]

I have a Palm T3 with scanner software and a OBDII cable but could not get that cable to work, something about the various types of OBDII cable configurations. ECUExplorer will also reset codes but only with a 90.00 cable. I do know that the Cobb AccessPort cable will work as well.

 

I would be very curious about what your KC is reading.

[Faster_nu]

For the quick learn look up the Vishnu reset, it explains the reset much better than I can.

[TSiWRX]

^ I would also advocate looking up the words "Vishnu Reset" on Nabisco or other sources of Subaru knowledge.

 

But simply stated, it's a matter of resetting your ECU first to factory default IAM of 0.5, and then quickly bumping it up to the "optimal" value of 1.0. What you're aiming for is between 2 and 6 PSI of boost, held for a few seconds, under moderate engine load. Typically, this means engaging third gear on a safe roadway, dropping vehicle road-speed to appx. 35 MPH, and then using left-foot braking, modulating brake application, to hold boost as indicated above (while maintaining safe road-speeds) until your ECU bumps the IAM from the default value of 0.5, obtained after either a battery negative terminal disconnect and residual charge purging or via electronic ECU reset, to an "optimal" value of 1.0.

 

For safety's sake, you'll want either a ride-along person to read-out your live boost pressure from a digital readout, or you'll want to use an easy-to-visualize boost-gauge. Your IAM can be confirmed via standard live dataloggers, and this value will jump rather quickly (within 5 seconds or so).

 

This is assuming that your ECU does not detect knock or potential knock activity during such a run - so it's best to do this with a properly warmed-up engine that's not heat-soaked, and with good fuel in the gas tank.

 

The debate over whether or not the Vishnu Reset is either necessary or if it can be potentially harmful to the vehicle is one that continues until this day.

 

The former is addressed by the fact that either on the stock ECU programming or, more so, with a good tune, the IAM will be maxed-out to 1.0 within relatively few miles/minutes traveled, after you've "exercised" the car throughout its rev-band a few times.

 

The issue of whether or not potential harm can come is more "gray." The Vishnu Reset aggressively pursues "optimal" IAM value, and in the process of doing so, you may incur knock. Typical road-driving, even spirited driving aimed at "exercising" the vehicle so that IAM is raised, still carries with it a certain safety factor in that the ECU looks at the vehicle through the entire range, and should safely pull timing - even checking IAM, if necessary - should knock be detected. With the Vishnu reset, you're essentially cheating/circumventing this safety cross-check, pegging-out the IAM for most aggressive performance, which then may cause the vehicle to push slightly over the safety envelope later on, as it continues to re-learn.

 

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PP - That latest log still looks somewhat funny to me.... the IATs just seem too high. What were the conditions like (i.e. road speed?, "snorkle" retained?), both when you took the log, as well as immediately previous (i.e. extensive idling? "racing" the engine?).

 

I kept an eye on my IAT this AM, on the way to work, and even at a cruise of only 35 MPH, my IAT on the very un-insulated and heat-soak prone Perrin Short Ram was only about 2 to 4 degrees (F.) higher than ambient, and this was within a half-minute after I took off from the stop-light, where it had sat for nearly 2 minutes (bumping IAT up to 84 deg. F., on a 42 deg. F. ambient temp. reading).

 

Also, like Faster_nu, I'd be interested to see what the rest of "the typical set" of logged parameters looks like, as well as a full 3-rd or even 4-th gear pull. The limited resolution on your datalogs, while it does show interesting considerations when paired with your 0-60 data, still gives a lot of blank spaces that we're unable to fill.

[Prime Power]

The outside temps were in the 70's, so a hot day. I believe those were WOT too. But they were high that day. Snorkel was retained.

[TSiWRX]

^ I'm not following......

 

http://www.legacygt.com/forums/attachment.php?attachmentid=32463&d=1171992607 - your last log.

 

Column 3 shows as IAT, column 5 shows as ambient. Is this incorrect as-displayed?

[Prime Power]

You are right, my bad. It got up to 70 that day, but not then I guess. Should have double checked. #'s don't lie. I don't want to take the time though to keep switching back from stock to SPT. I am happy with the comparison I did that one day. However I will keep logging to see what type of temps I am getting.

[Prime Power]

Can you guys give me a link to the download for that software. Would like to try it.

[TSiWRX]

PP - No problem RE: temps. I was just checking to see that *I* wasn't the one going crazy. Believe me, it's been proven many times that READING > ALLEN.

 

What concerns me is that big, big temperature gradient, and why, if your vehicle was indeed at-cruise, the IAT would not be lower. Given the difference in ambient to IAT, and how hot it could get in the summer, I'm actually almost afraid that you might run in to situations, even moreso than I do with my Perrin Short Ram, of heat-soak induced timing-pulls.

 

As for the datalogging software:

 

http://www.tari.co.za/cgi-bin/yabb2/YaBB.pl

 

That's the TARI Racing support Forum. The latest ECUExplorer download can be had from there, as well as your software/usage questions answered more directly.

 

There's a very good thread that detail datalogging, "Stickied" at the top of the Turbo Powertrains sub-Forum. You'll find that thread invaluable, and will provide excellent guidance (i.e. recommendations on what parameters to log, etc.).

 

Best of luck!

 

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Also, please believe me, bruddah, that I'm not trying to come down on you nor to paint the SPT intake in a bad light. I'm very interested in what your timed runs show, and I'm a sucker for "the intake sound," myself (which explains why I've spent money to get my car tuned so that it can run my chosen intake). I have also always wished that SoA/SPT would come forward with their long-promised data which was claimed to counter Cobb's claims against this intake ( but this data has yet to materialize ), since the use of this intake does not abridge the factory warranty, and this consideration is of utmost importance to many of our fellow LGT brothers and sisters.

[Prime Power]

No offense taken for sure. Hey, do think wrapping header wrap around the intake would help solve this. Yes, you would say bye-bye to the bling, but I wonder what benefits we would see?

[TSiWRX]

^ I honestly don't know.

 

There's debate that always rages as to whether or not using such insulation will help with intercooler piping...I'm still on the fence.

 

It would be, however, hard to quantify this difference - that's for-sure.

 

The problem exists in that we have only the IAT as the intake temperature sensor. Even our actual charge-temp is done via the complex ( or maybe even simple ) algorithms in our vehicle ECU.

 

As such, unless you were to somehow rig a POST-piping run temperature or actual charge-temperature measurement, this would be rather impossible to quantify.

 

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EDIT - Ooops, sorry, perhaps I took that a little too far.

 

I rather imagine that you mean what would happen if you further insulated the heat-shield provided by SPT for this intake, correct?

 

The problem there is two-fold.

 

First, you need to truly seal-off the intake area. This is somewhat difficult, as you'll need to trim sealing material around several non-standard/smooth areas, both in terms of hard-points as well as wiring harnesses and piping. The "seal" of these areas is even harder to achieve, as you'll need a material that provides a good-enough seal, while not tearing - and normal engine movement can make this quite hard to accomplish.

 

A good seal is very important - the air in there gets quite hot, and quite rapidly at that.

 

Second....well....I cut a piece of high-grade thermoplastic (something that we use in our labs to autoclave) and insulated it using that thick, insulating tape (BOTH sides, a sandwich, if you will) from ThermoTec. I even took care to seal everything.

 

Still not much improvement. Perhaps dropped everything 2 to 3 degrees, F., while driving, but at-standstill, there was still enough heat-transfer that I was well-above the point where our ECU would pull timing, and this was just sitting at my local "3-minute light."

[Prime Power]

Wow. I need to log my car with this. I downloaded it. Do I need to remove that green wire or whatever? And were is it. Also, I meant the intake tube as sealing off the area, well I would need some help to do that.

 

Also what model do I use on that software?

[TSiWRX]

^ The program should automatically "detect" your vehicle model, if I remember correctly. I haven't used it in a while, since I'm now using the ECUTeK DeltaDash.....

 

You will, however, need to know your "addresses" for IAM and engine load - hopefully, either TARI's Forums or others here could help you decipher that.

 

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Do I need to remove that green wire or whatever? And were is it.

 

The "Green Test Connector" should *not* be connected while you're driving your vehicle; nor is it necessary to connect that item for datalogging. Don't worry about it.

 

For reference, though, it should be in your passenger's side footwell, above where your "left" foot would be, underneath the corner of the carpeting that is the junction of the center console and the main console running across the car.

 

Also, I meant the intake tube as sealing off the area, well I would need some help to do that.

I'm not following ....sorry, but I don't quite understand what this means?

[Prime Power]

I didn't say that well. I was speaking of taking header wrap to the metal intake tube. I said that because I don't think I could do a good seal off from the engine.

[TSiWRX]

^ Gotcha.

[Prime Power]

I tried that software today, doesn't work with my cable. I ran some runs with my avalanche and it's intake temps was 13-21 above outside air. 13 at running speed. I have on it a k&n fipk II with the bottom of my truck cut out for air along with a ram air hood actually dumping cold air right on top. So I don't think my subbie is doing that bad. I would like to see stock #'s again. But I don't want to keep changing mine. I think the temp diif. is exponentially greater as the outside temps rise. My SPT was colder that day I keep doing switches between the two and believe it still would be on hotter days.

[Faster_nu]

I will take some photos of my K&N setup. I will also test intake temp and outside air temp and see what the varience is. Perhaps its the way the intake sits in the fender? Oh and I will send you the link for the cheapo cable.