Rolling Dyno SPT vs Factory

[Prime Power]

Purchased some nice software for my b-day and ran some test with the SPT intake vs. the Factory. I did 3 runs each, at about the same time, with the same temp, at the same place. All in sport mode, and the 60 times with no powerstall. Just flooring it from idle. The software auto detects the cars movement then starts the time. Did not have enough room or money in the wallet to try the 1/4. The hp and tq seemed to be about the same as far as max @ 255hp and 260 tq. The intake temps seemed to be about the same. The 60 times however where the difference.

 

Factory - 7.69, 7.45, 7.47

SPT - 7.37, 7.33, 7.34

A noticeable difference. Now this is my first time doing this sort of thing, so don't beat me up too bad. I am open to suggestions/criticism just be nice

One more thing, anyone find a fix for the stutter. It's there factory or SPT.

[sirsimon]

Hmmm, interesting numbers! It is cool to see some "real world" numbers on this.

 

Does it "feel" faster?

 

Do you have any other mods?

[Prime Power]

I have no other performance mods. I did get a faster time of 6.7 in the sport sharp mode, but decided to run these in sport. Also had turbo boost of 18 factory and I saw 19 with the SPT. Verified by both my gauge and the scan software. As far as feeling faster, maybe, but really it would be hard to tell that difference. It does feel stronger though in the midrange on normal driving.

[NSFW]

Interesting, thanks for posting this. What software did you use?

[fweasel]

 

One more thing, anyone find a fix for the stutter. It's there factory or SPT.

Yes, its in the ECU tuning.

[Prime Power]

I used autoenginuity.

 

As far as the ECU tuning, does the dealer have an update. I did not want to mess with it till it is out of warranty as far as reprogramming goes. Plus there is none for the 07's yet.

[Underdog]

AFAIK, you shouldn't be seeing 18 or 19psi boost on a stock tune, more like 13-14psi... Keep the 10th of a second anyways, I just want some more rumble! These stock cans are too good at noise suppression.

[Prime Power]

I thought it was too high too. Maybe it is just for a millisecond. I only know the max, not how long. As my eyes were on the road.

[Faster_nu]

Your using a SPT with the heat shield?

 

Do you use a OBD-II cable and a laptop with this? Does this software have the capability of showing the Knock Sensor timing adjustment, the timing, and the MAF flow? This will show you HP also as well as telling you if your running lean.

 

Try downloading ECUExporer and using it with your setup, It will work with a number of OBD-II cables. The software is free and it works great. It will allow you to Datalog your car showing you potential problems after modification.

 

Just look up the thread on Data logging.

 

Oh and Power Braking will take at least a second off your best times. With a 2900 takeoff you might be very surprised at 0-60 times.

[Prime Power]

It does allow me to data log, but not for sure what all I can log yet. I have done the MAF flow. Haven't done the knock sensor or timing though. I did a quick run today keeping the factory snorkel on and without it. Temps were average 4 degrees cooler. And yes I use the heat shield. I did a take off with about 2200rpm launch and was 6.5. I think I could bring it down with a higher rev.

[Faster_nu]

The reason that I am asking is that I have placed a K&N typhoon system on my Legacy GTW and have noticed my maf at 219 with the filter in place, I was told that all intake systems will make the engines run lean without a new map or a professional tune but after watching my MAF and Knock Sensor, it just isnt so with the K&N, but I was concerned after so may people replied to my post warning me.

 

I would be interested in looking at your logs, I can certainly post mine and seeing how the two systems are different.

 

I did not replace my snorkel on my system however I think I will try that, Did you have to cut it or make any other modificatons to it?

[Faster_nu]

Oh one thing that I forgot. I did reset my ECU and do a quick learn, that seemed to help tremendously. I think they call it a vishnu reset, from the same tuners that work with subarus.

[Prime Power]

I cut my heatshield to fit the snorkel. Here are some logs I did this morning. Don't know if that data will help to compare. I read our cars run rich, so adding one of these might even it out. This is at 65-75 and some with the snorkel on and then off, then on again.

[sirsimon]

Prime: A lot of people have complained about the increase in noise with the SPT intake. Some have indicated that the heatshield does reduce the noise of the intake. Can you comment on the noise level/quality, and if you find it to be detrimental?

[Prime Power]

I don't think it is as bad as some have said. But my tolerance may differ from theirs. My wife hasn't really complained, said more about the hogzaust then she did the intake.

[TSiWRX]

PP and Faster_nu :

 

Don't log the knock sensor - even at the fastest rate-of-capture, it's still not reliable enough to insure that you capture knock. Instead, log knock correction as well as IAM (which you can take off later, if your initial logs show that it is happy and steady at 1.0), and correlate that with timing.

 

PP - That posted log up-top, that's with the vehicle cruising at 65-75 MPH? That's actually higher IAT than what I see even with my Perrin Short Ram, without heat-shielding....

 

Your 0-60 results are very interesting indeed - maybe it does lean-out a little, thus giving you slightly more power? It certainly does seem that the SPT component is of-benefit on stock-ECU vehicles..... And I would also suspect this to be the case with Faster_nu's setup. I couldn't honestly tell y'all anything at all about what I saw/did-not-see with my Perrin Short Ram, when I initially rode with it using stock-ECU programming, but definitely, later, on the dyno w/wideband, it did show significant lean-plateaus. I believe that brother PhilT also logged slightly raised EGTs with the Perrin intake (again indicative of running a bit leaner), however, the K&N seems to at least not incite the latter concern.

 

Question for PP: Are you controlling for IAT at the beginning of your runs? Our ECU pulls timing quite drastically if the IATs are too high - although this would logically predict that the SPT should suffer from heat-induced lower-performance, it would seem that your data here does not bear this out (unless the IAT for your stock-airbox setup was initially higher).

 

I've been away for a while - does anyone know if SPT/SoA ever fully countered Cobb's testing of the SPT intake?

[Prime Power]

The temps were about 4 degrees higher on my stock setup than this. As far as controlling for IAT do you mean letting the car temps drop? Like I said, I am new to this. Too bad someone close can't come show me more about this. I will try logging my knock correction and IAM. I am on stock map and will be till the end of the warranty. One reason going with the SPT. I am a huge fan of K&N and have the 77 series on my avalanche. But really, for the price, some cheap plastic tubing is not what I wanted here, I wanted something better looking. I ran some logs with normal driving and the temps were about 2-4 degrees higher than outside the car. That seems pretty good to me. So I am not for sure about the heat soak question with the setup.

[TSiWRX]

Hey PP, thanks for your detailed reply.

 

 

The temps were about 4 degrees higher on my stock setup than this.

 

If that's the case, then it shouldn't have mattered. The resultant time-drop should equate to a real power gain.

 

As far as controlling for IAT do you mean letting the car temps drop?

 

Correct - or, alternatively, just starting your runs with the vehicle at the same observed IAT.

 

Like I said, I am new to this. Too bad someone close can't come show me more about this. I will try logging my knock correction and IAM.

 

No sweat, I'm new, too. We've all gotta start somewhere.

 

One of the more advanced guys/gals will be able to help interpret your logs better if you enabled "the standard set." Have a look-see on the "Datalogging" beginners thread, and you'll see which parameters are typically needed. For example, you'll definitely want to log timing as well, and it's the combination of that parameter, plus knock correction, that allows us to better visualize what's going on.

 

Iran some logs with normal driving and the temps were about 2-4 degrees higher than outside the car. That seems pretty good to me. So I am not for sure about the heat soak question with the setup.

 

2-4 deg. F. above ambient isn't bad at all - but your post here:

 

http://www.legacygt.com/forums/attachment.php?attachmentid=32358&d=1171758722

 

....shows anywhere from a 9 to 13 deg. F. difference - but more startingly, this is *at speed* - unless I'm reading something wrong?

[Prime Power]

You are reading it right, those were after and in between running some 0-60 times. My tranny gauge at this temp rarely evens moves above 120, but during that time I had it up to 180, so I was running the car. I was real curious and woke up the next morning and went out to do some looking. Then at normal driving it was 2-4 degrees, and I felt better. I will look over that thread and do some more sometime.

[TSiWRX]

Very interesting...I wonder what that was all about? I'm just as puzzled as you are/were about that!

[Prime Power]

I think it is cause I was really on the engine doing some 60 times.

[TSiWRX]

^ LOL. That certainly could do it.

[Faster_nu]

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

[Faster_nu]

Prime. Have you done any WOT or 0-60 runs with logging. It would apear at idle your car seems fine but I dont see the Knock Correction value? This would tell alot about whats happening. Looks like a good datalog though. WOT or Wide open Throttle will show you how much more air the car can use 200 seems about stock and anything over is a HP gain. If you look at the KC with WOT and the maximum MAF readings this should show you if your running lean. The moment that your KC becomes in the negatives indicates your running lean. Some correction would be ok but -5 and below is a sure sign of trouble. Stock runs from 0 to + 5 from what I have seen of other 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.? If what I have read is correct then the KC would be much higher in correction

[Faster_nu]

Do you think your car runs better? With my K&N it seems much smoother with alot more grunt in the start of a full throttle run. I dont think it has done that much for the top end, but thats much harder to feel.

 

I have used a GTECH Pro Competition, GTECH Pro SS, and a GTECH Pro RR to run 0-60 times and have faired much better with the K&N than stock. I was running 5.9 0-60 stock with power braking takeoff at 2900. However all my times were run in 30 degrees or less so it will fall off this summer.

 

I wrote a comparison article for the GTECH meters for a local rag, interesting enough they were all within .1 second of each other with the GTECH Pro RR and the GTECH Pro Competition being the exact same times. I kept the GETECH Pro RR so I will be doing some comparision runs datalogging time vrs the Gtech just to see if they are close.