Dyno Day Results

vettelovralexand · December 5, 2010

Well, today I went up to Centerville, OH to hang out with some of the guys from the Ohio Coal Rollers. The event took place at Proxses tuning (using a Dynocom DC1800x with eddy brake)and was mostly a bunch of diesel guys, but I took the opportunity to strap the truck down on the dyno both with the Blackbear ECM and with the stock ECM. I had 93 octane in the tank and the GMPP was obviously on the truck too. No other mods. In an attempt to not blow up a driveshaft we did 2 runs on each ecm with the truck in 3rd gear. The results aren't absolutely spectacular, but it did show a great improvement just with the tune change. The truck managed to pull ~277lb-ft and ~255hp on the stock ecm and then the BB tune managed ~290lb-ft and ~263hp. Just figured I would share the results. As soon as I am emailed the plots and videos I will share.

Jennabear · December 6, 2010

What RPM did you run it to? Thanks for sharing!

vettelovralexand · December 6, 2010

You are more than welcome Jenna. It was run all the way to the RPM limiter which I believe kicks in at about 6K(maybe 5800?). Without having the plots yet I am not entirely sure from memory. The peak torque was ~4500RPM and the peak power was at ~5400RPM if memory serves. I have a video of the attempt of a run in 2nd gear (didn't work out well due to the small load that had been set on the dyno) but not of the actual runs where we got the numbers from my previous post. I did attach a couple of the pictures of the truck on the dyno until I can get the video uploaded on Youtube.

vettelovralexand · December 6, 2010

Here is the video uploaded to Youtube of the 2nd gear pull.

pistonslap · December 6, 2010

http://www.gm-trucks.com/forums/style_imag...icons/icon9.gif

Five more foot lb's of torque on a 93 tune? Is that right? In this area i think the gas is rated at 87-89-93 octanes?

If i used a 87 tune then it would be even less.

vettelovralexand · December 6, 2010

http://www.gm-trucks.com/forums/style_imag...icons/icon9.gif

Five more foot lb's of torque on a 93 tune? Is that right? In this area i think the gas is rated at 87-89-93 octanes?

If i used a 87 tune then it would be even less.

Correct, it was about 5 more Lb-ft (at peak) with the 93 octane tune. This isn't the maximum gain. I still haven't received the plots (printer at the dyno broke due to the cold weather) so when I get them I will post them.

Gas in this area is either 87-89-93, 87-91-93, or 87-89-91 depending on the station.

On edit, my numbers from above are incorrect. It gained about 12lb-ft at peak torque, not 5 as I had thought. My first post is edited to reflect this change.

vettelovralexand · December 7, 2010

Alright. I have the actual run data in hand and have gone through and compared the best two runs to each other and created the dyno plots. It is attached in PDF form.

Stock_To_BB_Torque_Curves.pdf

vettelovralexand · December 8, 2010

Wow, I can't believe that as many people there are that are interested in getting their truck tuned that this thread garnered virtually no response.

[email protected] · December 8, 2010

Wow, I can't believe that as many people there are that are interested in getting there truck tuned that this thread garnered virtually no response.

haha. I thought the same thing! I appreciate the thread, so I will be saving my pennies

stlavsa · December 8, 2010

Wow, I can't believe that as many people there are that are interested in getting there truck tuned that this thread garnered virtually no response.

haha. I thought the same thing! I appreciate the thread, so I will be saving my pennies

Well I know the first time I looked I didn't see any graphs so i gave it a quick read and I closed it. Your gains are pretty much exactly what I expected from a dyno tune, maybe a little on the low side for peak (gains not whp numbers). My other problem is that its not a dynojet so the WOT passes are pretty much meaningless for anything more than a tuning stand point. (I cant look at the numbers you posted and compare them to the next guys).

Either way I do appreciate the post, as I am trying to decide if its worth tuning for 93 octane or 87 octane. At first I thought it was a no brainer but now the price of 93 octane is at $3.35 cents here and rising.

vettelovralexand · December 9, 2010

I do appreciate the feedback. I understand that you can't compare my numbers to others due to the fact that the dynos are different, but that will always be the case as different dynos even of the same type can seldom be compared. What I do know is that these runs were done literally back to back only 2 or 3 minutes apart so the test is truly showing the benefit of purely a tune switch. That is what I think people really want to know.

[email protected] · December 9, 2010

That is a good comparison when you put it that way.

I dont know the difference between the two dyno's...but realizing that, time to spend an hour on google...

stlavsa · December 10, 2010

That is a good comparison when you put it that way.

I dont know the difference between the two dyno's...but realizing that, time to spend an hour on google...

Well its basically like this there are a couple types of dynos associated with this type of measurement (rwhp). Theres brake dynos and inertia dynos.

An inertia dyno is something like a dynojet, (248, etc) It is the most popular inertia dyno. The other common type of dyno used for tuning whp is brake dyno. There are a myriad of brake dynos, mustang, dynodynamics, dynomite, dynocom, dynapack. etc etc. Thats where the discrepancies come into play.

While the brake type dynos are a more effective tuning tool, their output #'s can vary greatly. Some folks like them for tuning because they can simulate load and therefore you can theoretically do partial throttle tuning, where as the inertia dyno cannot simulate a load, and therefore WOT tuning is all you get. The problem with the load bearing brake type dynos is this: Parameters for operator input... The dyno operator can change parameters like the load, ramp time, brake force, blah blah and it can drastically affect the output numbers. (one guys mustang dyno can easily read 30whp more than the guys identical mustang dyno down the street).

Now when you take a look at specifially the DYNOJET inertia dyno, it is a more reliable way to compare numbers on vehicles anywhere. (though its not perfect). Generally they are setup identically, and theoretically, a vehicle should make about the same power on any dynojet. Of course it doesnt always work that way we all know there are exceptions to every rule, but for the most part its true. For this reason the dynojet is considered the industry standard, even though it lacks the features of part-throttle tuning.

Now in my opinion (take it for whats its worth as a novice, hobby tuner) I prefer using a dynojet. I use it for WOT tuning, and its also good for those guys who dont want to tune, but just want to strap their car/truck down and see what kind of power it makes. (doing this with any other kind of dyno is kinda pointless). Some tuners will come back and argue that you can only do WOT tuning, but really why are you trying to simulate road conditions with the dyno anyway?? Just take the car out on the street and tune part throttle in REAL WORLD CONDITIONS. Get all part throttle bugs worked out in the streets, then strap the car to a dynjet and do your WOT tuning. That way when u post a dyno you dont have to say welllll it reads low because its (insert random dyno name).

stlavsa · December 10, 2010

Another thing I dont want to take away from the OP thread. I was also pretty surprised at the lack of interest in this thread. It seems like every guy on here is worried about what programmer they want or what tune they have or who should tune their truck, or how to get more power blah blah blah.

I haven't did any tuning of these trucks yet, looking into it soon, probably going to do hptuners. BUT like i said these are the numbers I expected to see. Your initial post referred to gains of only 5 ft lbs etc and that seemed a little low to me, but then you posted the graphs, and you can see the area under the curve and how much better the new tune is. There are good chunks of that graph with 10+ whp and tq gains and thats more like what I expected from a black bear tune.

There truly is no better bang for your buck as there is with this tune. People blow $1000+ dollars on an exhaust system only to lose some low end torque and gain a couple peak whp. Its a truck, not a race car. I dont spend alot of time WOT at redline in this truck, because its a truck. I have owned fast cars and i realize that power to weight is much more important that 3 peak whp. If you wana go fast in this thing its gonna need big time power, through FI. other than that, I like the idea of getting a tune and maximizing the driveability of truck as is. Which is exactly what black bear and the other tuners are offering for a majority of folks and it really is a good modification to perform on these trucks.

I have the GMPP performance series exhaust, and I will construct a simple velocity stack short ram intake with heatshield, and then do the HPtuners, (or maybe even give black bear a try). And thats about it in the performance department... My big lifted truck isnt made for going fast anyways.

[email protected] · December 11, 2010

Hey thanks! That makes lots of sense. So for most guys getting the Black Bear where Justin does his thing, a Dynojet would be a good across the board comparison.