Speed Thrills

Took the ride to the "Dyno Store" in Chatsworth and it was quite an experience. They just opened 2 months ago and it really is a state of the art facility. The latest dyno equipment and several large plasma screens set up so you can see exactly what the car is doing as they run it through the tests. I didn't have my camera (my bad) but I did take several with my cell phone. I just cant figure out how to DL them to my computer yet.

Anyway, out of 3 runs my best was 443hp and 446 ft/lbs. They said my first run of 430hp was due to holding back a tad on the rpms and the car being hot from just bringing it in. The guys working there seemed very knowledgeable and were impressed by the loss % to the wheels. All and all it was a great experience and I can't wait until my after mod dyno next week. I will keep all posted. I'll also post the pics of the dyno shop and process when I figure out how to DL the pics.

Tony007

That's some serious power for a stock car. Be VERY interesting to see the after results!!

Are you still planning on the Kleemann K1 kit?

JamE55

Those are some very good numbers. I'm assuming this was done on a Dynojet Dyno?

Stiggs

Sorry guys, but I'm Dyno retarded. Are the numbers shown indicative of what is at the rear wheels....or is it what the engine is putting out?
Thanks

Speed Thrills

Rear Wheel HP.

RennTechV12

NICE NUMBERS!!!!

This says alot. It is probably as I suspected, M-B is understating the true HP/TQ of that motor. With an 18% drivetrain loss (which is typical in RWD cars) your cars is really putting out about 520hp at the flywheel.

I dynoed my SL600 before getting the RennTech Upgrade and it put out 469hp at the rear wheels or 553hp at the flywheel. This makes perfect sense because M-B put the same exact powertrain in the Maybach and rated that at 550hp.

Speed Thrills

Interesting. I wonder why they would publish the 469hp numbers. Maybe they dont want it to outshine the SL55 hp?

Vic55

Wow sweet numbers, I work right up the street from that store. What is the cost? I would love to see what I pull on their machine?

Whoopsy

either you had a especially sweet engine or MB detuned our engine on paper.

I think I read somewhere that the engine in the E55 puts out less hp than a SL because of a more restrictive intake and longer exhaust and our car is suppose to be the same as the E55.

Grumpy666

These dyno pulls were on a stock car? How were they able to rev past redline w/o hitting 155 mph cutoff? Were these pulls done in 3rd gear? If so, your numbers will be a little inflated. Can you confirm please?

RennTechV12

good point.

When we dyoned my car, it was put in "dyno mode" to avoid any computer interference.

rflow306

Grumpy third or fourth makes very little difference in peak horsepower. Victor and I have posted our dyno sheets in both gears.

What it doesn't show is whether these numbers are corrected or not. The graph usually displays the correction factor used std, sae, and uncorrected. It shows cf 1.00 on the bottom but doesn't show method.

jikjak

how do i put the car into dyno mode?

im planning to dyno mine as well to get a baseline number before modding

RennTechV12

Look HERE

Be careful with this. You have no computer angels on your shoulder when driving (ESP/ABS)

E552006

Has this worked on your 05 and 06 vehicles?

RennTechV12

only tried it on the '03 S600 and the '04 SL600

Grumpy666

An inertia chassis dyno does not directly measure the torque at the wheels of a car to determine the power produced. Instead, it measures the rate of change of acceleration of the roller, and then converts that to force (F=M*A), since the mass of the roller is known. The diameter of the roller is aslo known, so the force can then be converted to torque and finally to HP. The same parameters that affect the rate of acceleration of a car will affect the rate of acceleration of the dyno roller. These include transmission gear. rear-end ratio, tire diameter, tire slippage, etc. Even the weight of the flywheel in MT cars can have an effect.

vrus

Your car seems very healthy, but I think the dyno operator ran your car in 3rd gear. It isn't a 1:1 transmission ratio so the numbers aren't really accurate.

In 3rd gear your power will be inflated, but your torque will be deflated.

Based on your graph above, I would guess that if you ran in 4th you would probably be at 425 - 430rwhp, 470 - 480rwtq. That is one healthy motor you have! Congrats!

rflow306 made a few points for you to consider next time you dyno. Find out if they are using corrected #'s and if they are make sure they are using SAE correction factor.

Enjoy that beast of yours!

rflow306

Again, on an e55 the difference in peak hp is minimal. My definition of minimal is 1 to 4 hp. The third gear ratio is 1.41:1 while fourth is 1:1 hence their is a larger difference in the torque being displayed like Victor mentioned.

The dyno jet calculates the horsepower and then determines the torque value only when an rpm signal is present. If you get fluctuations from your rpm pick-up you will get incorrect torque values .

Stiggs

Is there a way to find out the actual horsepower the engine itself is putting out. I would be curious to see how much over 469 it is.

Speed Thrills

I'm pretty sure all three pulls were in 3rd gear but I do know these were corrected numbers. The uncorrected numbers were a lot higher and the guy that ran before me asked for the uncorrected numbers sheet so he could boast higher HP when selling the car.

Speed Thrills

That "Dyno Mode" post was interesting. When I go for my "after mod" dyno I will have them try that on a few extra runs. To see my real gains I will have to use the exact method as before though. Here is their info if anyone is in the area and wants a dyno. Great place and great people.
The Dyno Store 10040 #E Canoga Blvd, Chatsworth, Ca 91311 (818) 576-9373

Grumpy666

If you're talking about environmental conditions corrections, then the corrected numbers should be higher, not lower. Corrected numbers bring the result to sea-level standards. By a lot higher, what kind of numbers are you talking about?

vraa

Only if you do an engine dyno from what I know.

Or just take the numbers you get from rwhp and divide by .80 (which we assume will be the transmission loss on an automatic Mercedes, which is optimistic for the engine dyno).

Say you have 448rwhp.
448 / .8 = 560.
That means the engine is making 560hp (theoretical figures) if we consider that the transmission creates a 20% hp loss due to heat, friction, and whatever else.

Say we were really proud of our transmission and claim a 15% driveline loss. So lets do the equation again.
448rwhp (which we got from the dyno) / .85 = 527.

Stiggs

I'm confused, if you lose less (15%) in the drivetrain, then shouldn't the horsepower be more?