I-Club/NASIOC: BC Members' Dyno Scores

[steve]

Pat, I wouldn't complain if you posted the dynos. I'd love to compare how the other models fair on your dyno, if anything, to know where the rest of us stand. A stock WRX would really be great to see, both 2.oL and 2.5L.

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[Solar]

I had my stock 05 wrx dynoed on monday. I think Pat will be posting the stock wrx dyno plot. If not I will post it when I get the info on my computer.

[patr]

ok I just have to check with the owners (I am fairly positive they wont mind the 'before' plots) and I will put them up

[PentUpWrx]

The torque curve on my wrx after the tune is amazing, it is soo smooth all the way thru the power band. Shifting early and the car just plain pulls. Pat is bang on with the torque numbers vs peak hp. After seeing the curves and adjusting my driving style the car does not feel as fast... but it rips.

[patr]

ok I posted up all the legacy vs. stock etc. stuff on our site as well, its all here if you cant find the right message up above:

http://www.rocketrally.com/managed/m...geid-117.phtml

and 2 'bone stock' owners have agreed for us to post their pulls so that is all well, i will try to get at it tomorrow... plus an STi that pulls 350+ (on our dyno, same lack of correction etc, so that is a BIG number). There are a few more 300+ cars (400+ at crank) cars that I am still waiting for confirmation on.

[20pwns]

at the LGT torque numbers!
~190 ft.tq. jumps to ~275 ft.tq. with just a pipe and one ass-kickin' tune.
Props Pat, damn...

Jason L.

[patr]

(EDITED to make an easier read)

Here is some bone stock 05 WRX data for all of you (very similar results with the 02-05s, with just that the earlier models dont have the CL hiccup and a few minor changes).

All these pulls are from the same car with just a flash, **no uprated pipes at all**, all pulls within 15 minutes of each other with maximum advance and stabilized inlet temperatures for the specific test method. I show a minimum of 2 pulls in each method to verify that it is consistent, not a one off, and very real.

Bone stock 05 WRX - 177.2 uncorrected DD whp

and now that same bone stock car with JUST a flash

Bone Stock 05 WRX w/ Rocket Reflash - 198.3 uncorrected DD whp

Here they are comapred:

Bone Stock 05 WRX vs. Bone Stock 05 WRX /w Flash Only

Now, for the techie in you, I've also posted those with EXTREME ramp rate (i.e. super slow pull, high temeratures, and little to fanninh) - not what we normally do but useful for data gathering. This is the 'worst' it could read. Note that the relative gains percentage wise are similar, and I have included 2 pulls in each method to also demonstrate it is not 'flukey'.

Super Heat Soak Bone Stock 05 - 162.6 uncorrected DD whp
(you can really see the OL/CL hiccup here)

Super Heat Soak Bone Stock 05 w/ Rocket Reflash - 181.5 uncorrected DD whp

Here they are compared:

Super Heat Soak Bone Stock 05 vs. Heat Soak Bone Stock /w Flash ONLY

Note that we are not just "factoring the pulls by some number X", they are actually seperate pulls. To back it all up, the relative increase is almost exactly the same (percentage wise), when comparing normal pull mode gains vs. heavy ramp mode gains. This is all done just to have more 'comparative data'.

Everyone's graphs are published with the first method but I actually keep all data on method 2 as well (part of the tuning process).

For reference purposes, WRXes with just catbacks pulls 175-183.

normal stocker is ~165-175 range.

point being, if you dyno it a certain way, the same way, every time, its consistent. If you have inconsistent temps and fanning and correction and what not you can see +-5%. So if one guy comes in on a -10 day, and another guy at +40, you get some variance. We can publish correction factors, but temp correction SHOULD NOT BE USED on the dyno for tuning purposes. All the graphs we give our customers use the first method. That way if someone comes back 6 months later, it should be the same. 'nuff said.


-Pat

[patr]

We had a customer car in here the other day that made some very impressive results. They speak for themselves:



Note that this is higher than even the Mustang or DynoJet numbers for similar turbo, primirily due to the head work. It has a strengthened bottom end but that really doesn't add power, it just adds reliability. This is a daily driver than can do roll on burnouts in several gears. Don't ask how I know.

This is the new STi record. This is about 500 at the flywheel.

Rocket Custom Tune (a lot of extra dyno tuning to make it totally daily driver friendly), Rocket built bottom end, FP Green, Perrin FMIC, Ported and Polished Heads, Cams, etc.

[patr]

Here is another interesting link, for the techies out there.

This is all on the same car. You can see the difference between a max torque tune and a max power tune. Essentially, you can let the turbo run free in the midrange, but the heat collects and limits the numbers up top. This is the difference between an "all torque" tune and a medium blend of torque and hp (the final tune). The point being, you can make power where you want, but there is always a compromise. Thats why I always think its interesting when folks have an already made up whp number in their minds.

Here it is: the 'm17' is the all torque run. The other one is the final tune.

http://www.rocketrally.com/dloads/cu...a/508610-8.jpg

[Solar]

wow, thats powerful. would it be possible to post stock STI numbers?

[patr]

normally its ~215-220 for stock STi. Dont let the peak hp number confuse you though.. even tho its easy to make a WRX do that, the torque curve for the STi kills it in a major, major way.

Mustang dyno is usually 240. If they say its lower they are bragging.

[tony_subaru]

Originally Posted by patr

We had a customer car in here the other day that made some very impressive results. They speak for themselves:

Note that this is higher than even the Mustang or DynoJet numbers for similar turbo, primirily due to the head work. It has a strengthened bottom end but that really doesn't add power, it just adds reliability. This is a daily driver than can do roll on burnouts in several gears. Don't ask how I know.

This is the new STi record. This is about 500 at the flywheel.

Rocket Custom Tune (a lot of extra dyno tuning to make it totally daily driver friendly), Rocket built bottom end, FP Green, Perrin FMIC, Ported and Polished Heads, Cams, etc.

Was that one from Kelowna by chance?

[buster]

What kind of numbers do you guys add for crank hp? WRX drivetrain?

[patr]

Dyno Dynamics is much more accurate and better for load holding than the popular "whp" dyno (good example is the thickness of the line on their plots spans about 10hp on ours) - but it reads lower. For Mustang correction, you need to do 1.17 - 1.20. All bets are off if the Mustang pulls use 'atmospheric compensation' - which is actually invalid for turbo cars. I've been pained to not just in general insert a fixed a correction factor because it would save me a lot of headache but its against my principles to do so... but if people want we can always run it at 1.2 (trust me a lot of shops do this - many of which have 'claims to fame' in the proven power bragging forums). All of our pulls are uncorrected and do not use atmospheric compensation. The reason I try to show at least 2 semi-identical pulls in every plot on our site is to demonstrate that they aren't "best of" pulls and also that they are accurate.

You cant measure crank hp without an engine dyno - all you can use is emperical evidence from testing 'known' quantities to come up with correction factors to make 'estimates'. Gimmicks like coast-down etc. are not accurate. Nor is atmospheric compensation. Furthermore, estimates are not linear throughout a speed range or driveline friction envelope, or temperature envelope. I don't like estimating crank hp, because its meaningless (honestly). If you measure it at the wheels, before and after, the same way, that is what is important. THE SAME WAY is what is most important.

To show why it is bad to estimate, or rather, how it gets out of control:

A lot of Mustang guys are using more than 1.2 to estimate crank. But lets just say they use 1.2 to give them the benefit of doubt. 1.2, multiplied by * 1.17 (DD mustang conversion - conservative lower end again just for data purposes) is 1.416 (just for data purposes). So lets say 200 hp on DD is 234 on Mustang. 234 * 1.2 = 283.2 (typical mustang shop crank estimate). That would mean around 1.416 for a DD. But a lot of Mustang shops use more than 1.2 !! A lot of DD shops are using 1.4 (Dynocomp, APS, etc.). To say its over 500hp... 378 to get to 500 is like 1.3... you get the idea - its a very conservative estimate. I do them conservative beacuse its all BS (i.e. I am postitive its at least 500). So when your car gets dyon'd, what matters is RELATIVE not 'what some guy got on the internet'... When people get disapponted because they are expecting 300whp with their mods because that is what they think they should get, but on those same dynos the cars are starting out at 240, its a big difference to when you start out at 180. But generally speaking, for the WRX 1.35 to 1.4 on ours seems about right. BUT DONT DO IT, IT IS MEANINGLESS unless you are only really speaking to overall, ball park estimates.

There are many threads from old school here on Nasioc and at efi101.com and many other places explaining the differences, correction factors, etc. etc. Suffice to say, the inflation game is just that. Dynapack will over-read initial torque, then provide Dynojet-like numbers. Dynojet is double high because there is a Dynojet correction factor in there... twice ! Mustang reads low, but not as low as DD, but many mustang shops will say "our dyno reads soooo low". There are two well known nasioc vendors whos' claims of "210 for a stock STi on our Mustang dyno" have been corrected by management, and shown after the fact, in a seperate thread, on the low side. I can get a stock STi to pull 180 if i want to, I just have to drive it that way ! The more reputable Subaru shops with a DD are KTR performance (uses correction though), Vishnu, DynoComp, APS (internal use), etc. You can check out KTRs site (have a lot of plots up there) but keep in mind Franz uses atmos compensation (so he doesn't have to write long emails like this maybe) so his are a bit high. The only negative (if you want to call it that) about the DD is that it doesn't use any correction by default to give higher #s. None. At all. So it reads low, but accurate. You can see 3 hp easily.

Stock STi is ~210 (worst was 205, best was 215). Stock WRX is ~172 (worst was 165, best was 178). On 2WD or a FWD car its different. So we always compare before to after. But if you aren't after a number (which you shouldn't really be chasing), the best use of the dyno is for steady state tuning, which makes for a much more driveable car. You can ALWAYS make a higher pull from any customer tune I am sending out - but you want a tune that is driveable. To get the highest possible number is different than tuning it to daily drive and have most area under the curve.

(I am typing too much). Just remember we used to go down to run the Mustangs before we got ours so it isn't like we haven't used them first hand... and we bought DD even though it is almost twice the $$.

Anyways, that is a long ramble to answer the question, but i think as much information is needed out there concerning this, otherwise people jump to the wrong conclusions.

-Pat

[buster]

Wow....thanks Pat....I learned a few things just now.

[leeward]

I concur. I’ve been a good customer of a serious tuner in Portland who uses a Mustang. They too take no credence in the “number.” It’s only a reference to be used for test and tune. My STI ran 242 hp on their dyno with a down pipe, stock exhaust and the Perrin intake. After the Ecuteck reflash and a full exhaust, it made 298 hp. Either way, it’s irrelevant to the actual functioning of the ride. The Dyno Dynamics unit is a top-drawer tool! Rather than the front tires bobbling along on which ever roller they happen to land on, the DD unit adjusts to the perfect span. I’m pretty sure the DD's ability to hold a given rev is also a huge advantage. That’s why the Rocket Rally torque charts look so fat in the middle. Either that, or it is Pat’s ability as a racer that tells him this is what really makes cars go faster!

Thanks Rocket Rally for making my car totally rip – in any gear at any rev!! It’s so cool to have a shop with this capability so close to home.

[PentUpWrx]

After driving my rocket tune for approx 2k, I have to agree with Leeward on the great throttle responce in any gear at any speed. I am not running his power levels, but still is a blast everytime I drive it. The difference between a "shelf map" and a RR tune is night an day. I have found the sweet spot in the car and pulls are so smooth thru the gears. Pat, great to hear that motor you guys built put down some serious numbers. I see a PE or bigger in the near future, I have a disease that you are fueling. I am gonna try to write up a decent review of the drivability of the car, still very impressed.

[tora]

Hey Pent-up, how is the car running? Are we going to see you back down here again for some more work? Hope you are enjoying it, it's always nice to get people coming a long distance as it really makes us feel like our service is good enough that people are willing to make a trek for it.

[Solar]

Just a quick question, would tire circumfrence or gear ratios change the Dyno numbers or give abnormal readings?

[leeward]

G-REX05,

Nobody seems to be answering your question so I’ll give it a try. I asked this same question a few weeks back at the shop.

My understanding is that a dyno calculates the torque (twisting power) against the rotations of the dyno rollers. If the tire is a larger diameter, it will turn the rollers on the dyno a bit faster, but there will be a bit less torque. The theory is that these factors should equal out to + or – 0.

So … the diameter of your tire alone should not change the output number.

[patr]

what changes is based more on the rotational inertia and mass. i.e. wheels are never the same weight/mass so that has a bigger effect than anything else.

so lets just assume for the sake of argument that you somehow were able to find 2 wheel and tire sets that magically had the exact same weight and rotational inertia (not possible, but lets just assume it was), and they were of different diameter.

the engine output remains the same, if you used wheel speed to determine RPM the back to back dyno plots will be "shifted" slightly to the right or left, but the shape will remain the same. At least with our dyno. The number difference torque-wise should be negligible, however, since power is torque x RPM, the "peak" power may shift but its actually misleading since the torque has not changed. BUT since we use a true RPM pickup, not wheel speed, you get minimal if "negligible" changes. In other words, it doesn't change much. Not much AT ALL compared to the changes you will see from using heavier/lighter wheels.

This i further backed up by the fact that you get the exact same plots if you do pulls in 3rd, 4th, 5th (assuming temps are all inline for each pull, and you dont get out of control on the road speed since the frictional losses are a bit higher) - in other words, lets say up to 180 km/h, doesn't matter what gear you are in, you get the same plot - but reality is that temps are hard to control so and the frictional losses go up at very high speeds.

BUT, one thing to understand is that a LOT of dyno operators use wheel speed to get and RPM number, which means that the dynos plots will move A LOT if you change wheels. We use a direct RPM probe. You can tell if someone is using wheel speed if the HP and torque axes do not cross exactly at 5252 RPM.

But in reality, wheels are not the same weight. You can tell a difference from 15": to 18" ! But its not because of size, its because of the weight.And with the increase indiameter, you get slightly higher frictional losses because the wheel speed are up, but if its a small change, you won't see it much. If you are testing, for example, a small change, like one pipe and another pipe with a 1/4" difference, I would stick with the same wheels, but otherwise, I wouldn't worry about it.

[KLS]

i am getting my dyno score very very soon!! yeah!

[tora]

Andit will be very very high...

[feiron]

hahaha dang! such a teaser

[patr]

Actually in the last few weeks I've done a number of surprising cars, but I didn't want to be a post whore.

Some interesting tidbits:

stock vf39, stock exhaust (including stock dp and cat!), but FMIC and injectors (only mods). I tried this setup just for experimental purposes really, since almost everyone who goes FMIC has turbo this and exhaust. This was mostly to prove the point of an FMIC on an otherwise totlly stock setup, which we discussed on a thread here on van nasioc a while ago. This ran 270, which is way more than I thought it would do, its comparable to doing injectors, catless DP, wg port and catback (with the stock TMIC). We will have a car with all of the above (but still with bone stock turbo to show) in a few weeks. That was a surprise. No where near as laggy as I thought it would be. I ended up putting this on my car actually.

and

stock bottom end, FMIC and a bolt-on gt30R (not rotated, but bolt on style - similar to a new offering that will be released soon) - 350 (pump gas, 21-22psi) - but its not even pushing the turbo hard as the pulls are pretty much back to back consistent every time - and there is no drop off like on a green

remember, stock is ~220.

-Pat