Tomorrow my car goes under the knife to get the new ACT carbon-carbon clutch installed. I'm so busy this summer that I don't think I'll see her back until September. So before I take her in, I decided to go out for some 60-130 MPH runs. Nothing really spectacular, not trying to set any records -- just having a little fun to see the car's performance.
Today, Alekshop threw a dyno day at Newtech in Hayward, California. We had a pretty decent turn out and a few surprises. Alek collected the money, and I collected the dyno results. I'd say it went pretty smooth. Then at the end of the day, the dyno operator hooked up his monster Corvette and layed down an insane 885whp and 775wtq.
As early as Bimmerfest-2009 (maybe even earlier), ESS and I had been talking about supercharging the stroker. We were both 1/2 joking, and both 1/2 serious about it. ESS was always inspired by the challenge of supercharging the stroker and was always willing to take on the project.
A few months ago, I was asked by M3Post user 'per' to rate the efficiency of the different supercharger kits on the market. My first attempt was to simply calculate the ratio of GAIN/PSI (the ratio of whp gain vs. PSI boost). 'Per' quickly pointed out that I couldn't rate efficiency in that manner because my own results were included, and mine were skewed by my displacement increase. So, I came up with the same idea -- version-2: Efc = Gain / Displacement / Boost. The idea is to measure efficiency as a function of Gain, Displacement, and Boost.
The ACT (Advanced Clutch Technology) company has designed a twin-mass carbon-carbon high performance clutch for the E9x BMW M3's (6MT only). ACT is well known for their high performance and racing clutch designs.
During the run up to the Mojave Mile and Texas Mile, we started adding some VP Racing Q16 leaded race gasoline to boost our performance. Between Mojave and Texas, we switched to 100% Q16 and retuned the car for it. Q16 seemed like a logical choice because it's very high octane, leaded, and oxygenated -- just what we need for the moisture-rich Texas weather. I figured, I'm catless -- so what's the problem? ZZZZZZZZZt. WRONG ANSWER.
We had a simple idea: get enough horsepower to hit 200MPH in the standing mile. Thank goodness, things never work out exactly as you plan. In this case, that's a good thing because we wanted to break this project up into two phases (maybe more). Phase-1, go to the Mojave Mile and see what we can learn, apply any changes, and go compete at the Texas Mile. As we found out, it's a good thing we decided to "learn" locally -- because many things went wrong.
Strange Week for the ESS-46 Supercharged Stroker
This has been one of those weeks with my car that started out strange, and kept getting stranger. It all started last Saturday night while I was driving my ESS-46 home from Arizona (that's what I'm calling the SC stroker). After about 6 hours of driving I got a phone call that went something like this:
Robert, I heard you were running 6 PSI and made 550whp.
Yesterday I flew to Arizona to pick up the ESS Supercharged RS-46 stroker motor. Late the night before, Roman called to inform me that ESS wanted to make one last change to the basic kit, and that might take most of the following day to complete. When I arrived in Arizona I called Roman to come and pick me up at the airport. The only question on my mind was "did everything go as scheduled today?" So I was very pleased to hear Roman tell me "I'll be right there...I'm driving your car."
Driving impressions: RS-46 with ESS tune
My car has been on quite a journey. My first modification was a pulley, followed
by the Gruppe-M Intake, ESS Tune, AA Tune, Amuse Ericsson Exhaust, and then the
RS-46 stroker motor. The stroker motor had four separate tunes of its own: my
left-over AA tune, Company-A, Factory, and ESS. But before ESS received the car,
it went through even more changes. None of these dyno charts are posted (some
day I'll post them), but I also installed Dinan Throttle Bodies, Technocraft
Envy Intake, and I reinstalled my Ericsson exhaust onto the stroker in a catless
configuration. Knowing that I wouldn't need the Envy intake, I sold it before
turning over the car to ESS for ECU tuning, and then a stage-2 supercharger.
During the investigation of retrofitting the 09 iDrive into an earlier vehicle, I bought all of the programming tools necessary to do my own vehicle coding. The plan was to use the actual BMW tools and software, and not bootleg versions. It turns out that the retrofit is not really feasible, so I kind of put it on the back-burner. So now what do I do with the tools besides sell them or figure out how to program my own vehicle?
Many people have been asking about the latest dyno results for the RD Sport RS-46 stroker motor. Since I posted my last results in April, the car has been dyno'd many times and on many dynos. We've completed the ECU tuning, and eliminated the torque dip that was so prevalent in the previous dyno results.
Dyno Cheating:
As this thread states, its purpose is to discuss dyno cheating, how it's done, and how to prevent it. I'm hoping that people familiar with different dyno brands will lend their expertise to this discussion to help expose and prevent dyno cheating. As new dynos are discussed, I'll roll up the results into this message. If there's enough interest in this thread, I'll eventually make it a sticky.
Here is a picture of the new 3-disc (tri-mass) racing clutch and flywheel from BMW Motorsport. As far as I know, this clutch does not yet appear in BMW Motorsport catalogs. Also attached in a PDF file with higher resolution of the same picture.
Here's a set of conversion tables I worked up for octane ratings. The
European octane rating is RON, where as the US octane rating is an average of (RON+MON)/2.
The following table comes from the following web site:
http://www.btinternet.com/~madmole/R...RONMONPON.html
Many of you have been following the progress of the various RD Sport "Stroker Motor" projects (seen here), and others may not have heard of it at all. For those who haven't, the RD Sport "RS-46" stroker motor is much more than a larger displacement version of the BMW M3 V8 4.0L motor. The RS-46 is a complete turn-key motor, headers, exhaust, ECU-tune, including installation.
Many of you have followed the development of the RD Sport RS-46 stroker motor. For those of you who haven't heard about it, the RS-46 is a 4.6L stroker motor for the E9x V8. Your motor is taken out, bored, stroked, and reassembled as a 4.6L motor.
I waited five months for the Amuse Ericsson M480 Titanium exhaust to arrive, and when it did, I didn't have time to dyno test it. Now that SEMA is over, I put aside some time to dyno test the exhaust. Though the horsepower gains are modest, the torque gains are VERY impressive.
If you're considering changing the final drive ratio in your BMW, the cheapest approach is to simply replace your existing final drive ratio with one of Dan's @ DiffsOnline. But there are also options to replace your differential at the same time. I'll explain those options below.
In this original thread on m3post (here), the discussion started with a comparision of the stock 3.85 final drive and the new Dinan 4.10 final drive for the 6MT. Soon that discussion morphed into a general comparison between 6MT and DCT and all combinations of final drive ratios.
An ECU upgrade affects a broad range of motor performance. Therefore comparing before and after results cannot be summed up by a single number. Max HP and max toque will not be enough; we need to look at the entire graph of performance over the broad RPM range.
An ECU upgrade affects a broad range of motor performance. Therefore comparing before and after results cannot be summed up by a single number. Max HP and max toque will not be enough; we need to look at the entire graph of performance over the broad RPM range.
Here's instructions for removing and replacing the ECU. These instructions are specific to the E9x M3's and will be slightly different on E9x 335's.
The Gruppe-M cold air intake looks fantastic, but doesn't really seal in the engine bay. The "seal" is made by screwing the molded air filter housing against the body of the car. A rubber seam in the filter housing mates with the body molding to make the seal. It doesn't seal nearly as nice as the factory unit, but makes up for it in the looks department.
Here's the dyno results for 2008 BMW M3 with EvoSport Underdrive Pulley on 91 octane gas.
Here's the dyno results for 2008 BMW M3 on 100 octane gas. This is the same exact configuration as my 91 octane baseline run: bone stock car, albeit 100 octane gas.
I thought it would be a good idea to write up instructions for dynoing the M3 motor on a hub-attached dyno. Hub-attached dyno's (such as the Dynapack, and Rototest) are going to offer the most accurate results -- far more accurate than any type of roller, or chassis dyno. Hub-attached dynos are more accurate because they operate on the same principles as a real motor dyno. Motor dyno's work by running the motor at wide-open-throttle, then applying a hydraulic load on the motor until it bogs down to a specified RPM. Once you arrive at your desired RPM, a torque sensors measures the amount of torque at the crankshaft.
Before any modifications were added to any vehicle, it's important to perform a baseline dyno run. The baseline is important because all future modifications will be made and compared to this configuration. The following baseline was performed when the car was completely stock.
Until I supercharged my car, most all of my dyno performance tests were performed on a Dynapack dynamometer. With your original dyno files and the right tools, it's easy to view, compare, and print your own Dynapack dyno results. Below are detailed instructions for viewing and comparing files from a Dynapack dyno.
In the mid 1980's, I worked at a very prestigious auto racing manufacturer (Drake Engineering), where I ran the high performance street car division. While employed I witnessed the meticulous design and testing methodology that helped them win Indy-500 twenty-six times. Using standard scientific methods were the hallmark of their design and testing methodology. Every design was dyno tested on a 1000hp Henan-Freud dyno. I learned the advantages of real motor dynos, and learned why roller (inertial) dynos did more to guess horsepower than to measure it.
