Dyno results (finally!). Knocking on 400

[Croak]

I finally managed to get my car on a dyno today, over six months since I installed my RMS aftercooler, 37.5# injectors, and RMS software. Been busy as hell at work, and couldn't find a shop that would do a Saturday run within easy driving distance, until last week.

The shop that did the dyno runs, Crawford Performance, is mostly a Subaru place, and these guys know their shit when it comes to Subarus and forced induction, but that's just a blurb, doesn't really have any bearing on the dyno runs themselves, though it was fun to overlay my plots against some of their hotter WRX and STI runs.

My setup is a '93 325is, with a transplanted '95 3.0 OBD1 M3 motor and transmission, with a 3.38 LSD and LTW flywheel. Supercharger is Dinan/Vortech V2SQ, running a 3.5" Euro HFM, Dinan big bore throttle body, 37.5# injectors, RMS aftercooler, RMS software, Dinan cat-back exhaust.

Ignition is stock Bremi coils, plugs are NGK BKR7EIX, fuel is 91 octane Chevron pump gas. I'm running EvoSport underdrive pulleys, and the 318 clutch fan that Dinan supplies with the SC kit, with a stock radiator. Stock OBD1 exhaust manifolds, stock '95 cats. Water injection is disconnected.

6" crank pulley, 3.33" SC pulley.

Ok, to the good part, and I'll get the actual charts up as soon as I can scan them, or get a good digital picture, since my camera and the scanner are both at work, and if I go in now, I may be stuck there for awhile.

1st run:

5th gear
70.2 degrees F outside temp
29.9 Barometric pressure
51.1 Relative Humidity

Peak HP @ 7000 RPM: 395.1 HP SAE corrected, 10.9 PSI boost
Peak TQ @ 5600 RPM: 274.7 TQ SAE corrected

2nd run:
4th gear
70.7 degrees F outside temp
29.9 Barometric pressure
51.1 Relative Humidity

Peak HP @ 7000 RPM: 388.7 HP SAE corrected 10.80 PSI boost
Peak TQ @ 5600 RPM :272.8 TQ SAE corrected

Using a 17% correction factor (which I don't trust), the Dynapack software was saying that I'm at 462.2 flywheel hp, but that really doesn't count or matter, since it's all about RWHP

The AFR/Lamba is interesting, I'm running a bit rich in the midrange, and leaning out a hair too much in the last 500 RPM, but nothing dangerous. Also of note was that the SC belt was slipping a bit, you could smell it cooking during the runs.

As to why the first run was done in 5th gear, with a Dynapack, unlike a roller dyno, top speed isn't an issue, and with a 1:1 final drive ratio the shop owner thought I'd get more accurate, (if possibly lower), numbers. The first run showed 152 MPH.

I had them do the second run in 4th gear just for a more apples to apples comparision to what I had done in the past, and for better comparision to most of the dyno runs done by folks here on BF.C, which are usually 4th gear. As you can see, not a lot of difference, the loss can easily be attributed to a little heat soak between the runs.

I had a third and final run done in 4th gear, and it was identical to the 2nd run, less than .2 TQ difference.

Needless to say, I'm very pleased with the numbers, they're higher than I expected, though it is a Dynapack hub dyno, not a Dynojet or Mustang roller dyno. And like I said, just as soon as I can get the charts scanned I'll upload them.

To put this in perspective, last March or April I did three dyno runs, at the same approximate boost levels, with no aftercooler, just the Aquamist system, 3.5" MAF, software from somewhere else, and 28.8# injectors. I made 301 HP and 257 TQ.

[///M4life]

yea i heard of that shop before. i used to live in fallbrook which is right off the 15 norht from you guys. anywyas great numbers. is this a stock block or did u do some internal work. btw beautiful car great job

[Croak]

Totally stock internals, 90k miles on the motor.

[///M4life]

wow i though u couldnt do more than 8psi on a stock motor. well u have given me hope. i have a friend in fallbrook his name is george he has a rms stage III built s52 up to 3.3l u guys should meet. his car is beautiful. hes been trying to sell and part it for a while. i think he has about 454rwhp in that thing. that would be kool to see

[96cosmosM3]

Nice numbers! And on 91 octane also, makes me want to keep and install my supercharger. What size pulley are you running on the charger itself?

Also, was the the baseline dyno on dynapack also or on dynojet?

[///M3ryder NY]

congrats croak...those r impressive numbers to say the least!

[Croak]

HP/TQ on run #1, crappy camcorder still shot, forgive the quality. If you squint you can see a faint line overlaid, that's the second run, in 4th gear.

Also, the charts they gave me had the "corrected" flywheel TQ instead of the wheel TQ, that's why it reads so high on the chart, look to the margin on the right for the real TQ peak.

[Croak]

Boost/Lambda, run #1, same apology as the first picture.

[Serious]

WOW good numbers!!!!!!

get us some vid's on that thing.

[Croak]

Originally Posted by 96cosmosM3

Nice numbers! And on 91 octane also, makes me want to keep and install my supercharger. What size pulley are you running on the charger itself?

Also, was the the baseline dyno on dynapack also or on dynojet?

6" Buldogge crank pulley, 3.33" Vortech pulley

Baseline was on a Dyno Dynamics roller dyno.

[bimmerpwr]

Great numbers, congrats!

[sgi4side]

Congrat!!!!! How did you do it? please share with us. What mod made the biggest difference in power gain. This has to be the most powerful stock 3.0L supercharged RMS car.

[hansmaester]

Incredible,
Basically with the addition of a better tune and RMS Aftercooler gain of approx 100 HP. That gives me a whole bunch of hope for 400 rwhp.
Congrats! Now just get rid of that belt slip.

How does the car feel?

[hansmaester]

With a 6" pulley what boost are you making off idle?
Me running the 5" still, I make like ~2psi @ 1500 rpm. Just curious if it jumps up to like 4 or more.
Anyone?

[mpowerme]

Man that's awesome. That car must fly!

[IMPORTEDCARS]

Congradulations Croak great #'s especcially on 91 octane!

[MrBlonde]

Good numbers, FI BMWs are what we are all about! Now get the Wookie out of it and see what it will run at a drag strip!

[highboostingm3]

Congratulations Croak!
That is awesome! We have to meet up! We live so darn close. Have fun with that bad boy!

[fast4d]

I miss my vortechs

[DakarDave]

Croak - 400rwhp on 91 octane gas with a supercharger is not an easy task.. I can count the # of vortech based kits @ 400rwhp on one hand...

congrats!

[Croak]

It's not 400 yet, but thanks.

And Kenny...I'm more like the wookie than I am Han, size wise. But with a lot less hair. I could probably shave off a couple 1/10th just by going on a diet for a month or so.

[jmc]

Awesome numbers, whats next? I know you want to break the 400hp number

JMC

[Croak]

I feel pretty confident that tweaks to the tuning can get me there. And I haven't went down the headers or cams or track pipe route yet, if I really start itching for more power.

But believe it or not, even before I got the dyno numbers, I was really satisfied with the power of the car since the aftercooler install. Smooth, fast, reliable, it's my daily driver, and it's been hassle-free.

So if all I manage to get done with a re-tune is smooth out the AFR's so they look pretty on a dyno chart, I'd walk away happy.

[paul e]

I dont know why I didnt see this before. Guess i thought the dynopak graphs were too hard to see the details in.. Anyway, heres my question.... Its stated that PEAK boost achieved on the run depicted is 10.8 psi at redline. But I decided to take a good look at the boost curve.. And you know what it says? AT redline, depicted at 7053 rpms, boost is 12.7 psi, not 10.8 psi.. Assuming 15 whp per psi, this misstatement of peak boost would account for 30 whp.. So instead of making 395 whp, its making 365 whp at 10.8 psi. How much do underdrive pullies account for... 10 whp? So now my whp results done in 96 degree fla look just like these.. Cept I dont have the obdi manifold.. cause im not obdi! naturally...

What am I misreading here... why is the boost peak quoted at 10.8 psi, when the plot clearly shows 12.7 at redline?

[///M3ryder NY]

Nice find Paul. Certainly would explain the difference between your numbers and croaks!