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Post your dyno results I had a dyno done recently,and a custom tune I'm very happy...This heavy girl is starting to give me the same feel my vette does.The power band has increased to the point I can really feel the tune add-on way downin the seat of my pants.

Im feeling way more grunt and Im getting scratch in all four gears hard!! Its is a sound that makes a car guy smile ear to ear.

I can see the passenger now fighting the G's, thats worth the trip right there,as they grab the "Oh Sheet handle"when I hit it hard!!.



This dyno info is going to be confirmed soon at another shop however feel free to post your findings and any other info concerning dynoing you ride..
 

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Discussion Starter #2
Rumpass posted this data on another thread its a great read.

I didnt author this. It is a copy-paste done w/o prior consent or approval (from another's copy-paste efforts I found online)

This should help us all understand the difference between the two major dynos, and as to why there are considerable differences in their output readings.....


"It's been said that a man with a watch always knows the correct time, but a man with two watches is never really sure. Unfortunately, there are no proverbs about a man with two knowing how much power his car really makes. In this article, we'll examine two popular chassis dynamometers and explain why each will give us a different rear-wheel horsepower for the same engine. We test both the Dynojet model 248 chassis dyno located at Strope's Speed Shop in Washington, Pennsylvania and the MD-250 Mustang chassis dyno located at Speed Nation in McDonald, Pennsylvania. We also performed testing at Keystone Raceway in New Alexandria, Pennsylvania, using a dyno system
from West Automotive Performance Engineering.


Dynojet
The Dynojet chassis dyno is referred to as an inertia-type dynamometer, because large drums provide an inertial load to the drivetrain instead of a friction brake. The working end of the Dynojet includes two 48-inch diameter drums that are mostly below the surface and driven by the vehicle's drive wheels. In the photos of the Dynojet, notice how the rear wheels are centered on the drums and there is one drum per wheel. This will become important later.
The vehicle is typically run in the transmission gear closest to 1:1 (Forth gear for manuals and Third gear for automatics) to or a variable load that maintains a preset engine rpm or vehicle speed. This feature is ideal for forcing the vehicle to operate at certain loads for tuning. The Dynojet can also measure air/fuel ratio while testing.


Mustang
The Mustang chassis dyno uses an Inertia load as well as an eddycurrent brake load to simulate the "actual" load (combined aerodynamic plus rolling frictional load) that the vehicle would experience when in motion. Notice in the photos how the rear wheels sit between two smaller 10.7-inch diameter rollers. There has been some discussion about the tires getting "pinched" between the rollers and creating more rolling friction, but no substantial evidence of this could be found. However, Mustang has a dyno (MD-1750) with a single 50-inch diameter roller per wheel that alleviates the wheel-pinch concerns. The internals of the Mustang dyno are composed of an eddy current brake to provide a variable load and an inertial disc to provide a fixed load. Mustang claims because its dyno loads the vehicle as it would be on the road, you can perform 0-60 mph, 0-100 mph, and quarter-mile measurements on its chassis dyno. Speed Nation has obtained quarter mile times within 0.1 second of actual runs at the track. We're not sure how the launch dynamics are simulated on the Mustang dyno, which
includes weight transfer, acceleration, jerk (the derivative of acceleration - how fast the acceleration occurs) and some other variables. The Mustang dyno can also measure the air/fuel ratio while testing.


CorrectIon Factors
Correction factors are used by both dynos to account for varying atmospheric conditions such as temperature, pressure, and humidity. The measured horsepower and torque are multiplied by the correction factor to obtain the corrected values. This is similar to the corrected times and speeds provided by some quarter mile tracks. Theoretically, you can dyno on a hot day in the high altitude of Denver and on some other cool day at sea level and produce the same corrected horsepower even though the observed horsepower you are producing at each location is different. Both dynos calculate a correction factor based on a Society of Automotive Engineering document (SAE-J1349). When testing was performed on the Dynojet, the correction factor was 1.10, which means the observed numbers were multiplied by 1.10 (adding 10 percent) to get the corrected values. The correction factor for the day when testing was performed on the Mustang dyno was 0.9595 (removing 4.05 percent). The correction factor when road-testing at
Keystone Raceway was 0.962, a correction reduction of 3.8 percent.


Testing
Testing was performed on each dyno using a '00 six-speed Z28 Camaro. We measured the horsepower and torque versus engine rpm in Second, Third, and Fourth gear. The test data also included how fast the engine accelerated in Second and Third gear (in rpm versus time) to be compared with actual road tests to assess each dyno's loading of the drivetrain. After each individual test we let the engine coolant temperature as displayed by our AutoTap OBD-II scanner to read between 200 and 205 degrees F for consistency. Dynojet sent out a representative to Strope's Speed Shop to verify calibration and witness testing. Calibration for the Dynojet is just a matter of verifying that the computer's configure file has the proper load-roller inertia factor. There are no manual calibrations for the Dynojet.
The road tests were pertorrned at Keystone Raceway to provide a level surface to measure the vehicle's rpm versus time in Second and Third gear using AutoTap. Chad Fellabaum of C&C Racing in Pennsylvania weighed the car so the exact weight could be used for the Mustang dyno loading to be compared with the road tests.
The dyno curve charts show horsepower and torque versus rpm in Third gears for both chassis dynos. You can also see that the Dynojet dyno measures a higher rear-wheel horsepower than the Mustang dyno.
The Dynojet measured 5.1 percent higher horsepower in Fourth gear, 7 percent higher horsepower in Third gear, and 8.2 percent higher horsepower in Second gear. We will try and explain this difference a little later.
Graphs 8 and 9 show the engine rpm versus time when the vehicle was loaded by the Dynojet dyno, Mustang dyno, and the actual road loading at Keystone Raceway in Third gear. You can see that the Mustang dyno loaded the car much closer to the actual loading in Second and Third gears.
Why Is loading the Vehicle Important?
The answer to this Question is twofold. First, the engine produces horsepower at the flywheel (brake horsepower) that is reported by the automobile manufacturers. Engine power is coupled to the rear wheels by a transmission and a rearend. But this is no free ride - there are losses in both the trans and the rearend. Therefore, the power to the rear wheels is equal to the flywheel horsepower minus the drivetrain power loss. The drivetrain losses are
mainly composed of three loss areas: friction loss, inertia loss, and viscous loss. The friction loss is largely due to the surfaces of the gear teeth rubbing against each other. Gear friction is related to the torque being transmitted through the drivetrain. The gear power loss is related to the speed at which the torque is being transmitted. This is why it is recommended to have a transmission cooler for towing. The transmission must couple more torque to pull the boat resulting in more frictional power loss, which shows up as more heat in the transmission to be taken away by the transmission cooler.
Inertial loss is related to the rotational acceleration (i.e., angular acceleration) of the drivetrain components. The inertial loss does not result in a power loss (i.e., heat) but absorbs energy that can be coupled to the rear wheels. This energy actually gets stored in the drivetrain components. The stored inertial energy in the flywheel keeps the revs up while the clutch is pressed in during shifts. The inertia loss is more pronounced in lower gears (i.e., First or Second) when the acceleration is highest. The viscous loss is basically the pumping of lubrication fluid in the transmission and the rearend. This is one reason why you get better e.t's when the
drivetrain is warm, because the oil is thinner and provides less "pumping loss." Therefore, to measure the actual rear-wheel horsepower, the drivetrain must be properly loaded to obtain the correct drivetrain loss. If the dyno provides a lower drivetrain load, then the drivetrain losses will be lower and the resulting rear-wheel horsepower will be higher.
The second reason why vehicle loading is important is that the newer computer-controlled vehicles use engine load as a control parameter. For example, ignition timing is a function of engine load. You will see higher timing advance when revving the engine in Neutral than you will when the vehicle is fully loaded at wide-open throttle in Third gear. This engine loading factor (and airflow dynamics, which is beyond the scope of this article) can help explain why some people have dyno'd identical to a friend's engine on a Dynojet dyno but got different results on a Mustang dyno.
Which Dyno Measures the Actual Rear-Wheel Horsepower?
West Automotive Performance Engineering has developed a proprietary device that independently measures a vehicle's actual speed and acceleration. This device is similar in operation to a fifth wheel but doesn't use accelerometers that can be influenced by the vehicle's body tilt. Using the vehicle's speed, acceleration, and weight (mass) and the application of simple physics equations, the exact horsepower and torque can be calculated. The horsepower and torque measured by West Automotive Performance Engineering's dyno is actually the horsepower made-good, or the horsepower left over to accelerate the vehicle after all the aerodynamic and rolling-friction losses have been overcome. These losses were accounted for and included West Automotive Performance Engineering's dyno so that a comparison with a chassis dynamometer can be made. The Mustang dyno includes the aerodynamic load that it places on the drivetrain as part of its reported rear-wheel horsepower and torque. Stated another way, the Mustang dyno does not measure the horsepower made-good.
Graphs 7 and 10 show the horsepower and torque versus rpm in Second and Third gear, respectively, for the Dynojet dyno, the Mustang dyno, and from road testing with the dyno from West Automotive Performance Engineering. You can see that the horsepower and the torque, as measured on the road, are closer to the Mustang dyno measurements. Also from the acceleration tests you can see how the Mustang dyno loads the vehicle very closely to how it will be actually loaded on the road. Based on our test data, the Mustang dyno loaded our test vehicle and measured the rearwheel horsepower closer to what the vehicle experiences on the road.

Conclusions

The Test Results table summarizes the testing that we performed. Keep in mind that the peak numbers are influenced by the amount of smoothing or averaging done to the final data. For comparing dyno plots to determine losses or gains, don't focus on the peak values but take a visual average by comparing the before and after curves on the same graph. If you can't see a marked improvement on the dyno, you probably won't see a performance improvement on the street. Also, realize that both the Dynojet and Mustang chassis dynamometers are useful tools that have excellent repeatability. Both dynos measure the correct horsepower and torque for the load that they apply. Both dynos will show losses or gains from modifications. It is recommended that you pick a dyno for your baseline testing and stick with that dyno type and dyno location (and dyno operator) for subsequent testing. Always start at the same engine coolant temperatures before each run. Also, use an OBD-II diagnostic scanner like AutoTap (from B&B Electronics) to monitor your engine's operating parameters. This will provide the best indication of power improvements or losses. We like to monitor the engine-coolant temperature, timing advance, knock retard, pre-cat O2 voltage, and rpm. Monitoring the engine-coolant temperature lets you make sure your engine is at the same temperature before each run to produce the most consistent results. The timing advance and knock retard indicate if any detonation is occurring that results in reduced timing and lower horsepower. After doing some research, the pre-cat O2 voltage can provide a correlation to the air/fuel ratio even though the O2 sensors are not too reliable in this air/fuel ratio region.

The bottom line:

Dyno numbers are for show, and track times are for the dough!"

-author unknown
 

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This is my dyno after a custom tune at FASTLANE, with MBRP exhaust and Techco CAI. It will be a couple of months before I get it tuned and re-dynoed after getting SCREWED.

Ambient temperature was 98*F, humidity around 80%, and hood was open.
 

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Here are my before numbers with headers, mbrp, Techco CAI, 85mm TB
 
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Discussion Starter #5
Hmmmmmmmmmm.
I thinking headers big time now I see some of the numbers from others like Venthos BTW, 70TA nice results buddy......The RT is real kiddies...Never doubted it one bit its one fast car for the buck... :).
 
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Discussion Starter #6
I cant wait to see the numbers from the many SC techno folks...
Im thinking techo for a xmas gift to myself..The wifes gonna love that!LOL.

This is my dyno after a custom tune at FASTLANE, with MBRP exhaust and Techco CAI. It will be a couple of months before I get it tuned and re-dynoed after getting SCREWED.

Ambient temperature was 98*F, humidity around 80%, and hood was open.
 

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We just installed a KB Twin Screw @ 9-10# we made 502 rwhp and like 498 rwtrq! with 93 pump gas.I'll try and post the graph later but for some reason right now when i try to post the photo it keeps comming up error..JL
 

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380 rwhp, 380 rwtq. Dynajet, about 80 degrees out with 75% humidity.

Predator, CAI, 180 tstat.

On the UPS truck somewhere from Andy at PWR is Corsa and Hurst six speed. Next delivery after that is a 150 shot nitrous. Then we'll take it back to the dyno boys, get it set up properly again and see what we can see...
 

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I just got tuned yesterday.

Dynomite Dynomometer

SRT8 6spd with AEFIS stage2, MM 85mm TB, 180t-stat, MBRP and custom tune

395RWHP and 394torque

I figured I'd be in the 400-410 area but seems as if our 6spds are suffering with a tremendous 18%loss
 
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Discussion Starter #11
Great info Guys we all seem to be in the same area!!

Im getting another dyno done in a month or so,and I'll post all the info as well as we all should.Its great to compare numbers..

Great thread thankyou Speedy good stuff as usual from you ...
 

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Stock vs. Magnaflow vs. Magnaflow + Mopar CAI

Stock: 335HP 358TQ
Final: 348HP 373TQ

This is AWESOME! Thanks for doing this.
 

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624 rwhp
564 rwtq

k.
 

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Thats great. Do you run race gas all the time? Isnt that super expensive? Did you try a 93 tune?
 

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Thats great. Do you run race gas all the time? Isnt that super expensive? Did you try a 93 tune?
SRT8 w/ 10.3 compression and a twin screw super charger putting out 12 lbs of boost in 4/10ths of a second.

the motor would be dead in 5/10th's of a second using 91 octane fuel (i live in California, 91 octane is the highest pump gas available)

kevin
 

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how expensive is 105?
 

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Well I am not sure where this thread is going. But in any event I believe the initial request was for numbers. Track performance is another matter depending on the driver tires etc,..
For anyone's interest.. numbers on my SRT8, with cat back and CAI were 358/343 after Predator, Procharger, Kook headers and a moderate ( not final ) tune the numbers show 491/478..
The on road performance is the real issue. This machine pulls so strong now through all the gears especially in the RPM band over 2700. It is a hoot to drive!
Kojak & "CHEKM8"
 

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The Car:
2009 Dodge Challenger R/T - w track-pack
6-speed Tremec T6060
TorRed for extra HP
3:73 rear end gear ratio with limited slip

Current Mods:
Diablosport Predator Tuner - 93 CAI tune
K&N CAI
JBA catless mids
Magnaflow catback exhaust
NOESP mod
180* thermostat
BT Catch Can
Hotchkis Sway Bars
Cool Stickers that add HP!

The Results:
364HP, 396TQ Run Conditions 74.33*F



 
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