Dyno Rematch: Battle between Dinan & RD Sport for 4.6L Stroker Motor Bragging Rights

[regular guy]

Dyno Rematch: Battle between Dinan and RD Sport for 4.6 Liter Stroker Motor Bragging Rights

Introduction

A few months ago, I participated in the original Dinan vs. RD Sport Stroker Motor dyno shootout. I was the guy behind the scenes collecting all of the data and who wrote it all up. (Read the original article for reference.) The RD Sport motor was the clear winner that day. But the Dinan ECU tune showed some problems that may explain its lackluster performance. The Dinan ECU tune showed the throttle bodies partially closing and reopening between 5500 to 8400 RPMs, where the RD Sport and other vehicles dyno'd that day didn't. The owner of the Dinan vehicle was concerned, contacted Dinan who promised to look into it and fix the tune. So almost from the very beginning, it seemed like a rematch was inevitable.

Dinan Retuning

Dinan spent considerable time with this car checking, rechecking, and retuning. The 100-Cell High Flow Cats of the Akrapovic Evolution exhaust were removed and exchanged for a Dinan CATLESS X-Pipe. To accommodate the CATLESS configruation, Dinan upgraded the ECU to their Stage-2 software. These changes alone should add some horsepower. But it's unclear if it would be enough to catch up and surpass the RD Sport stroker.


RD Sport Retuning

The owner of the RD Sport car didn't sit idly by while his Dinan counterpart underwent exhaust and tuning surgery. This owner decided to stay with his original 100-Cell High Flow Cats Akrapovic Evolution exhaust, but he did update his ECU tune. The original tune was provided by RD Sport as part of the stroker package. The new ECU tune was provided by ESS Tuning. This new ECU tune for the NA stroker was originally developed a few years ago as part of their development of a supercharged stroker project. Would this be enough to keep the RD Sport advantage over the Dinan CATLESS exhaust and Stage-2 ECU Tune?

Before answering any of these questions and looking at the results, let's recap each project for people not familiar with the original tests.

The Dinan Stroker

The Dinan stroker comes in a complete turn-key package. If you don't want to send in your own motor in advance, Dinan will build up one of their cores and ship you the engine as soon as it's completed. They charge you a nominal core charge which is refunded as soon as your engine is received. To gain maximum power from the Dinan stroker, Dinan also recommends to purchase Dinan stage-2 intake, Dinan throttle bodies, 16% underdrive pulley, and free flow exhaust. Although these accessories cost extra, Dinan does list them as optional to achieve maximum power.


Price: $25,999, includes:

• Bore: 94mm / Stroke: 83mm (4608 cc displacement)
• Compression Ratio: 12.0:1
• Dinan proprietary billet crankshaft
• Dinan proprietary lightweight forged pistons
• Dinan proprietary light-weight connecting rods
• Balanced and blueprinted
• Dinan electronics and engine management software
• Dinan serial numbered block

Optional Equipment / Expenses:

• Exhaust
• Under drive pulley
• Stage-2 inake
• Throttle bodies
• Installation

Rated power output (measured at crankshaft):

• 502 horsepower @ 7500-7800 RPMs *
• 384 ft-lbs torque @ 5600 RPMs *
• 527 horsepower @ 7800 RPMs **
• 407 ft-lbs torque @ 5200 RPMs **

* Engine tested using 93 octane with High Flow Intake Stage 2, Throttle Bodies, 16% underdrive pulley and Free Flow Mufflers
** Engine tested same as (*) above, but with BOTH CAT delete, Dinan racing mid-pipe, and Dinan racing exhaust.

The RD Sport Stroker

The RD Sport stroker also comes in a complete turn-key package. Just as with Dinan, if you don't want to send in your motor in advance, RD Sport will build one for you from one of their available cores. The RD Sport stroker comes in two flavors: 1) Basic Stroker, 2) Full Stroker Package. RD Sport also offers custom stroker packages using custom strokes (82mm - 85mm), custom bore sizes (up to 94mm,), low compression pistons for supercharged applications, and Carrillo H-Beam-HD connecting rods for supercharged stroker applications. RD Sport has built both high and low compression stroker motors from 4.4L to 4.7L displacements.


Price: $23,995 includes (Basic Stroker Package)

• Bore: 93mm / Stroker: 85mm (4619 cc displacement)
• Compression Ratio: 12.0:1
• RD Sport billet crankshaft
• Mahle lightweight forged pistons
• Carrillo H-Beam connecting rods
• Balanced and blueprinted
• 16% Underdrive pulley
• RD Sport engine management software

Price: $32,995 includes (Full Stroker Package)

• All of the above
• RD Sport proprietary long tube headers
• RD Sport high flow CATs
• RD Sport mid pipe
• RD Sport high flow exhaust

Optional Equipment / Expenses ***

• Front bumper which also serves more air to the intake system
• Installation

Rated power output (measured at crankshaft):

• 480 horsepower @ 7700 RPMs *
• 387 ft-lbs @ 4800 RPMs *
• 525 horsepower @ 7700 RPMs **
• 425 ft-lbs @ 4800 RPMs **

* Basic Stroker Package tested with 91 octane gasoline, stock exhaust
** Full Stroker Package tested with 96 octane gasoline
*** Installation is free when RD Sport has access to the car

A Third Entry into the battle

Just like my original Stroker shootout, a third entry wasn't planned...but just happened. In the original shootout, the third entry was a full bolt-on Limerock Edition M3 that ended up dynoing slightly higher peak whp than the Dinan Stroker. That won't happen on the rematch, as the third entry is a bone stock 2011 E90 M3. The bone stock entry will provide valuable calibration data by running on the same dyno with the same conditions. These results can be used to compare everything from throttle valve operation to AFR and spark advance. It's a great third entry into the shootout.

Testing Methodology

Over the past few years, I've run many dyno days and tested approximately 40-50 BMW M3's. I test each car with the same methodology and as time goes on, I've developed the ability to data log many important parameters and incorporate them into our dyno charts. Today's methodology is as follows:

• Neither Dinan nor RD Sport were notified in advance of this test. They knew a rematch would occur but were not notified when or where it would occur.
• Three or more dyno runs until the car doesn't make any more power.
• Use best three runs, regardless.
• Dyno each car in same gear (4th gear).
• Attempt to dyno each car at same engine temperatures.
• Heat soak test the car to see if it degrades performance. Runs are usually about 2-minutes apart or less. This induces a heat soak test to see how the car performs under stressful back to back conditions.
• Data Logging with BT Tool
  • RPM
  • Throttle Position
  • Gear Selection
  • Intake Air Temperature (IAT)
  • Spark Advance (can see knock)
  • Both O2 Sensors (converts to Air-Fuel-Ratio)
  • Oil Temperature
  • Water Temperature
• Data Logging with Kestrel Weather Station. This allows us to verify accuracy of Dyno weather station and the Dyno horsepower correction formulas. This prevents cheating.
  • Temperature
  • Barometric pressure
  • Humidity
  • Density Altitude

Prices as tested (MSRP prices, excluding installation):

Dinan price as tested: $38,195

• Dinan 4.6L Stroker Motor
• Dinan Throttle Bodies
• Dinan Underdrive Pulley
• Dinan Stage-2 Intake
• Dinan High Flow Middle Racing Exhaust for BMW M3 E9x
• Dinan Racing Middle Exhaust Software for BMW M3 E9x
• Akrapovic Evolution Exhaust
• Full CATLESS

RD Sport price as tested: $29,995

• RD Sport 4.6L Stroker Motor
• RD Sport Underdrive Pulley
• Akrapovic Evolution Exhaust
• 100-CELL High Flow Cats

Bone Stock price as tested: $0

• 2011 E90 M3
• Bone Stock
• 91 Octane
• DCT

Results
This is the part of the report I call the "Data Storm." I will present the data we collected, and let you be the judge of what it means. I'm sure these results won't quell the debate about horsepower, cost, building strokers, etc. At the very bottom, I will make some observations about the rematch and how each one performed and improved.

Dyno Charts (SAE Correction):



Dyno Charts (STD Correction):




Dyno Charts (Uncorrected):




Horsepower & Torque Comparison:




Spark, Throttle, AFR, & Conditions Comparison:




Mapping the run conditions

To keep everything consistent between the original shootout and rematch, I've graphed the engine data logs during the entire dyno session to see how the temperatures changed during the entire event. The graph of the Stock M3 runs look a little funky because the BT Tool used to collect the data logs froze during its second dyno run.

Dinan



RD Sport



Stock M3




Post Mortem

In the original Stroker shootout, the Dinan stroker was tested first, so in the rematch I reversed that to dyno the RD Sport stroker first. The original test was an early summer morning, and the rematch was a brisk winter mid day. In spite of the seasonal differences, the actual dyno running conditions were nearly identical.

It's very clear from these results that Dinan has retuned this car. In the previous shootout, the ECU was closing the throttle bodies, and the spark advance seemed very odd and unlike most timing charts I've seen. This was a clear indication of a problem in the Dinan tune. Both of these problems now seem gone. The throttle bodies now stay open over the entire RPM range, and the spark advance is very similar to stock and RD Sport/ESS tunes.

The Dinan stroker picked up approximately 10whp over the original shootout. But the Dinan stroker was now CATLESS and included a Stage-2 ECU tune. So it seems very likely that the increase in Dinan power may mostly be due to these changes with some smaller benefits to the upgraded ECU tune.

The ESS tuned RD Sport stroker gave almost identical results to the original shootout. The top horsepower was the same, but the ESS tuned stroker picked up a little mid range torque. For all intents and purposes, the results were very similar.

The bone stock provided very valuable calibration data for this test. This told us how the dyno was reading on that day at that time. Most stock cars we put on this dyno will give between 330-345 whp. This 2011 E90 dyno'd a little lower than that which confirmed out suspicions that it was just one of those days where things were reading a little lower than normal.

Last but not least, if you find any errors, please let me know. Some of this was cut-paste from other entries, so it's entirely possible I made some mistakes. Please send a PM if any mistakes are found and I will correct them immediately.

In the following posts, I will dive deeper into the results of each dyno. If you follow the links below to the Dyno Database, all of the files and spreadsheets used for these tests may be found, downloaded, and analyzed on your own.

[regular guy]

Car and Modifications:

• 2011 BMW M3
• Dinan 4.6L Stroker Motor
• Dinan Underdrive Pulley
• Dinan Stage-2 Intake
• Dinan Throttle Bodies
• Both CATLESS
• Dinan X-Pipe
• Akrapovic Evolution Exhaust
• Dinan Stage-2 ECU Tune
• 91 Octane
• DCT

Conditions (Dynojet Weather Station):

• Temperature:: 68.26 degrees F
• Atmospheric pressure: 29.94 inHg
• Humidity: 45%
• Density Altitude: 211 Ft.
• SAE Correction: 0.968
• STD Correction: 0.996
• Uncorrected: 1.000

Results:

• SAE Corrected: 386whp @ 8110 RPM, 303wtq @ 4250 RPM
• STD Corrected: 397whp, 312wtq
• Uncorrected: 398whp, 313wtq

Dyno Database:

• Dyno files are available from the links below.
• SAE Corrected, STD Corrected, Uncorrected

Individual Dyno Results:
Individual dyno results are shown below. SAE corrected results are shown twice, using two different sources. The first source (djc) are the SAE corrected results straight from the Dynojet. The second source (sae) of SAE corrected results are obtained by using the Kestral 4500 weather station data for each individual dyno run and running it through an independent SAE correction formula. This ensures that the dyno results are accurate and can be independently audited and verified for authenticity and accuracy.
The legend below has the following meaning:

• Dyno Run: Dyno run file
• Timestamp
• Temp(F) = Temperature (Farenheit)
• RelH = Relative Humidity
• Pressure(Hg) = Barometric Pressure
• DA(ft) = Density Altitude
• IAT = Intake Air Temperature
• Oil(F) = Oil Temperature (Farenheit)
• O2(F) = Water Temperature (Farenheit)
• WHP(unc) = Uncorrected wheel horsepower
• WTQ(unc) = Uncorrected wheel torque
• WHP(SAEd) = Dynojet SAE corrected wheel horsepower (SAE-1340 PRE-2004)
• WTQ(SAEd) = Dynojet corrected wheel torque (SAE-1349 PRE-2004)
• WHP(SAEk) = SAE-Adapted wheel horsepower (SAE-1349 2004+)
• WTQ(SAEk) = SAE-Adapted wheel torque (SAE-1349 2004+)

* Entry used for the Dyno Database

Graphs:
SAE Correction:


Comparison with Baseline:




STD Correction:


Uncorrected:


Engine Vital Statistics:


Comparison for all runs:



Post Mortem

The Dinan stroker still underperformed the RD Sport stroker. They were within a few whp of each other, but that may mostly be due to going CATLESS vs. high flow CATs and a slight benefit to updated ECU tuning. Even though the Dinan stroker was CATLESS in the rematch, it still wasn't enough to run down the RD Sport stroker in either horsepower or torque.

It's very clear from these results that Dinan improved the tuning of this car. The throttle valves are staying open over the entire RPM range, and the spark advance looks almost like RD Sport and ESS tuning curves. The AFR's appear to be a little rich still however -- at least richer than the ESS tune in the RD Sport stroker, and strangely a little richer than even stock. It's possible, maybe even likely that the tuning could get a little more aggressive and pick up the missing horsepower and torque.

[regular guy]

Car and Modifications:

• 2009 BMW M3
• RD Sport 4.6L Stroker Motor
• RD Sport Underdrive Pulley
• Akrapovic Evolution Exhaust
• ESS Tuning "Stroker" Tune
• 91 Octane
• DCT

Conditions (Dynojet Weather Station):

• Temperature:: 69.68 degrees F
• Atmospheric pressure: 30.10 inHg
• Humidity: 45%
• Density Altitude: 176 Ft.
• SAE Correction: 0.971
• STD Correction: 0.998
• Uncorrected: 1.000

Results:

• SAE Corrected: 391whp @ 7630 RPM, 321wtq @ 3890 RPM
• STD Corrected: 402whp, 330wtq
• Uncorrected: 403whp, 330wtq

Dyno Database:

• Dyno files are available from the links below.
• SAE Corrected, STD Corrected, Uncorrected

Individual Dyno Results:
Individual dyno results are shown below. SAE corrected results are shown twice, using two different sources. The first source (djc) are the SAE corrected results straight from the Dynojet. The second source (sae) of SAE corrected results are obtained by using the Kestral 4500 weather station data for each individual dyno run and running it through an independent SAE correction formula. This ensures that the dyno results are accurate and can be independently audited and verified for authenticity and accuracy.

The legend below has the following meaning:

• Dyno Run: Dyno run file
• Timestamp
• Temp(F) = Temperature (Farenheit)
• RelH = Relative Humidity
• Pressure(Hg) = Barometric Pressure
• DA(ft) = Density Altitude
• IAT = Intake Air Temperature
• Oil(F) = Oil Temperature (Farenheit)
• O2(F) = Water Temperature (Farenheit)
• WHP(unc) = Uncorrected wheel horsepower
• WTQ(unc) = Uncorrected wheel torque
• WHP(SAEd) = Dynojet SAE corrected wheel horsepower (SAE-1340 PRE-2004)
• WTQ(SAEd) = Dynojet corrected wheel torque (SAE-1349 PRE-2004)
• WHP(SAEk) = SAE-Adapted wheel horsepower (SAE-1349 2004+)
• WTQ(SAEk) = SAE-Adapted wheel torque (SAE-1349 2004+)

* Entry used for the Dyno Database

Graphs:
SAE Correction:


Comparison with Baseline:



STD Correction:


Uncorrected:


Engine Vital Statistics:


Comparison for all runs:



Post Mortem

In the rematch, the RD Sport stroker still came out on top by a pretty significant margin. The RD Stroker remained intact with 100-Cell high flow CATs (HFC's) and upgraded the tuning to the ESS Tuning Stroker tune. In spite of the disadvantage of the HFC's to the Dinan CATLESS, the ESS tuned RD Sport stroker still won by 16 peak whp and 22 peak wtq. The ESS upgraded tune picked up approximately 5 wtq in the midrange and gave the same overall peak horsepower results.

[regular guy]

Car and Modifications:

• 2011 BMW M3
• Bone Stock
• 91 Octane
• DCT

Conditions (Dynojet Weather Station):

• Temperature:: 72.98 degrees F
• Atmospheric pressure: 30.13 inHg
• Humidity: 38%
• Density Altitude: 140 Ft.
• SAE Correction: 0.972
• STD Correction: 1.000
• Uncorrected: 1.000

Results:

• SAE Corrected: 327whp @ 8150 RPM, 242wtq @ 4010 RPM
• STD Corrected: 336whp, 248wtq
• Uncorrected: 336whp, 248wtq

Dyno Database:

• Dyno files are available from the links below.
• SAE Corrected, STD Corrected, Uncorrected

Individual Dyno Results:
Individual dyno results are shown below. SAE corrected results are shown twice, using two different sources. The first source (djc) are the SAE corrected results straight from the Dynojet. The second source (sae) of SAE corrected results are obtained by using the Kestral 4500 weather station data for each individual dyno run and running it through an independent SAE correction formula. This ensures that the dyno results are accurate and can be independently audited and verified for authenticity and accuracy.
The legend below has the following meaning:

• Dyno Run: Dyno run file
• Timestamp
• Temp(F) = Temperature (Farenheit)
• RelH = Relative Humidity
• Pressure(Hg) = Barometric Pressure
• DA(ft) = Density Altitude
• IAT = Intake Air Temperature
• Oil(F) = Oil Temperature (Farenheit)
• O2(F) = Water Temperature (Farenheit)
• WHP(unc) = Uncorrected wheel horsepower
• WTQ(unc) = Uncorrected wheel torque
• WHP(SAEd) = Dynojet SAE corrected wheel horsepower (SAE-1340 PRE-2004)
• WTQ(SAEd) = Dynojet corrected wheel torque (SAE-1349 PRE-2004)
• WHP(SAEk) = SAE-Adapted wheel horsepower (SAE-1349 2004+)
• WTQ(SAEk) = SAE-Adapted wheel torque (SAE-1349 2004+)

* Entry used for the Dyno Database

Graphs:
SAE Correction:


STD Correction:


Uncorrected:


Engine Vital Statistics:


Comparison for all runs:



Post Mortem

The additional bone stock entry into the competition gave is a great opportunity to calibrate and compare. It allowed us to compare spark, AFR, throttle valve opening all against these modified monsters to see how far from normal they may have deviated. For the most part, it appears that the Dinan tuned stroker and ESS Tuned RD Sport stroker maintain very stock looking spark curves. They differ a little on AFR's where Dinan AFR's look stock (if not a little richer) and the ESS Tuning AFR's look a little leaner.

Since most stock cars usually dyno between 330-345 whp on this dyno, the stock car told us the dyno may be reading a little low that day.

[Irishace]

Seriously underwhelming results for $25k+ modification. Thanks for posting, its illuminating in a not so good way.

[dparm]

What integration level was the stock M3 at? There are marked changes in the tuning on the latest 240E software.

Also, why was the stock car dynoed with 91 when the others got 93? They should all be at 93 octane to keep things level. We know for a fact the car will develop more power on 93 octane compared to 91.

I'd like to see a new dyno of that stock M3 with a 240E integration level and 93 octane fuel. That might explain why you see the dyno as "reading a bit low".

[tom @ eas]

Interesting. We just dynoed a 4.6L RD Stroker over the weekend and saw higher power numbers than what you're seeing. Only mods were Intake and Catless X-pipe.

TQ numbers are on the spot, which is awesome for NA.

[Longboarder]

Nice work RG. Would be nice to see these cars run against each others. How 'bout bringing them down to Willow for Shift-S3ctor this weekend

[Alex07M3]

wow, depressing numbers!!

What I'd like to know is the impressions of the guy who just dropped $38k at Dinan for an increase of ~60whp, worth it or not!!? The guy better have a big collection of cars to feel good after dropping that kind of money in his M3 for such poor gains!! That's +600$/hp!!

[dparm]

regular_guy, if you're willing to host the images I would be willing to generate the thrust curves for each vehicle. Might be an interesting perspective on how well those powerbands align to the gearing. PM me.

[IMG]

Very impressive RG and great work !

[crispy tofu]

great write up. nothing better than good old hard data.

[klammer]

This is pretty disappointing IMHO. I've always wanted to go for more power down the road, but always wanted to keep it NA. After seeing this...and for the cost

[CSL_E36]

I was waiting for this thread all weekend, clearly RG put a lot of time in documenting this rematch and hat tip to you sir for your diligent work.

The results are so sad I don't know what to say other then BMW has clearly got everything they can from this S65. Even their own GTS with 4.4L is rated at 444bhp and thats a minuscule and appropriate increase of 40 bhp from 10% increase in displacement from a 414bhp motor. YET, we enthusiasts were to believe that Dinan and RDsport were able to "untap" another 70 bhp from .2L of displacement? (4.4 to 4.6) On pump gas nonetheless! These results seem in line with reality, and seem very poor for the company's advertising 500+bhp from a NA S65 on pump gas.

[regular guy]

Originally Posted by dparm

What integration level was the stock M3 at? There are marked changes in the tuning on the latest 240E software.

Also, why was the stock car dynoed with 91 when the others got 93? They should all be at 93 octane to keep things level. We know for a fact the car will develop more power on 93 octane compared to 91.

I'd like to see a new dyno of that stock M3 with a 240E integration level and 93 octane fuel. That might explain why you see the dyno as "reading a bit low".

None of us are tuners so we don't know the integration level of the stock M3. I asked the owner when the last time it was service, and if I recall correctly it hasn't been in for a software upgrade since it was new. That likely means whatever was in the car when purchased in 2011 is the current integration level. The car owner is on the forum and he might chime in as I'm not really sure.

These cars were all dyno'd on 91 octane. I think you saw the comments I quoted from the Dinan web site that said their original testing was 93 octane. All of these were definitely 91.

Originally Posted by dparm

regular_guy, if you're willing to host the images I would be willing to generate the thrust curves for each vehicle. Might be an interesting perspective on how well those powerbands align to the gearing. PM me.

Sure no problem. I'll shoot you a PM with my email address. Hopefully everything in the spreadsheets downloadable with the files have all of the stuff you need except gearing.

Originally Posted by Irishace

Seriously underwhelming results for $25k+ modification. Thanks for posting, its illuminating in a not so good way.

Originally Posted by klammer

This is pretty disappointing IMHO. I've always wanted to go for more power down the road, but always wanted to keep it NA. After seeing this...and for the cost

I think a lot of people expect more than 15% performance gain out of a stroker because of the price tag. At the end of the day, a stroker is a 15% increase in displacement on the same engine. If you get more than 15% extra power out of it, it's icing on the cake.

[Billj747]

That's only 10-15whp over test pipes and a tune. Although torque is up a bit. It would have been nice to see that torque curve remain near 300 at redline rather than falling off.

[dparm]

If anyone is curious about the thrust curves, here they are based on the above data. This assumes all the cars had the stock 265/35R19 rear tires.

Thrust = (Engine Torque x Gear Reduction x Final Drive Reduction) / (Wheel Diameter / 2)

You graph thrust on the Y-axis and speed on the X-axis. What you're looking for is how well the lines come close to meeting each other. It's an effective way of showing how well the gears are setup for the car's powerband size (width) and location (RPM range). Also helps you determine optimal shift points.


Stock





Dinan





RD Sport






Some obvious conclusions:

1. Shifting at redline is not advantageous in any gear for any of those cars. Optimal shift points are about 100-200rpm short of redline in every gear.
2. RD Sport's stroker generates more thrust than Dinan's.
3. The DCT is geared to a top speed of around 205mph.
4. Even in stock form, the car makes excellent use of its powerband. All of the curves intersect the following one. This is not very common for a street car, especially for the 1/2 and 2/3 shifts.

[sterile stork]

I love data, and all the thought that you put into your conditions. Thank you for the wonderful contribution to the community.

[motortrend]

I don't understand why people expect such huge power gains from a small increase in displacement.

[M3ANMACHINE]

Thanks for the very informative thread, but what a waste of money..

[Sandye90m3]

So that $25k+, is that the amount you have to pay including giving your engine to the manufacturers?

Or is it 25K initially, and then they refund you a little bit for your core engine?

[StealYourFace]

Originally Posted by motortrend

I don't understand why people expect such huge power gains from a small increase in displacement.

Because other manufacturers engines see substantial gains with either larger displacement, or cam/heads changes. And for dramatically less $$

It shows that this engine is pretty well maxed from the factory, and as far as bang for the buck goes, you are better off with primary cat delete and either benvo, or evolve or one of the other tunes that will get very close to the power of these strokers.

It also shows that as awesome as that engine is, it just isn't all that efficient at making power. Especially when fuel consumption is factored. But, it is still a worthy product, because of the sound and feel of the power delivery.

I still want one, because it is a fantastic all around car... but there are other cars out there too that are bargains, are also fun, and can make more power more effectively.

Great post though!