so I went to a dyno shop today to make a apointment for my baseline tomorow night its a 1 year old AWD dynojet. I went to talk to the owner and check out his place very cool. I am installing my cmr tune and afe intake over the weekend so I wanted to get a baseline 1st.
While I was there i saw a black Rs4 getting dynod bone stock,,he made 288 whp and 291 whp??
wtf! they are rated 420 hp (like us) and only make that to the wheels??
I will **** if i get those numbers! I though our cars dyno 340-350 whp stock
also there was a c63 amg before him he said that guy made 367 whp

hmmm, that does seem a lil on the low end. hell with those kinds of readouts i would expect that you'd see 300 for the Jeep.

RS4's dyno stupid low. I was at a buddies shop once and a guy brought in an RS4 and had it dyno'd. 290whp. he insisted that the dyno was broken.


It wasn't.

found this amazing article but for a R8 vs jeep srt8.. r8 has same motor as rs4 check it out

On the Dyno
With 420 hp at its command, the output of Jeep's 6.1-liter pushrod V8 matches that of the direct-injection 4.2-liter DOHC V8 in the R8. To help reveal the different personalities of these engines, we ran both car and SUV on a DTS all-wheel-drive chassis dyno.

First, the Audi spun the rollers to the tune of 339 hp, demonstrating a nicely flat torque curve that peaked at 277 pound-feet. Then the Jeep belted out 373 hp and 360 lb-ft. Pick a point anywhere in the Jeep V8's rev range and you'll find it generates more torque than the Audi, but this pushrod V8 hits the wall at 6,300 rpm whereas the Audi pulls all the way to 7,900 rpm. This higher-revving nature lets the Audi take better advantage of gearing.

What stands out most is the difference in peak power. Both V8s are connected to similar all-wheel-drive systems, so driveline losses should be roughly similar. And since both engines are claimed to generate the same power at the flywheel, they should put down very close to the same power as measured at the wheels. Yet the Jeep threw down a full 34-hp more than the Audi, so what's going on here?

One conclusion might be that either the Jeep's output is underrated by the factory or the Audi is overrated, or some combination of the two. Another theory is that the high-compression Audi V8 is more sensitive to fuel octane than the relatively understressed Jeep engine, and the crummy 91-octane fuel here in California affected the Audi's output more than the Jeep's

even the r8 dynod 34 whp less than srt8 . maybe our cars are under rated?

2cnd part i thought was interesting..

Straight-Line Performance
The R8's dash to 60 mph in 4.2 seconds and its run through the quarter-mile in 12.7 seconds at 110.7 mph demonstrates that license-incinerating performance and a calm disposition can coexist peacefully.

However, the Jeep's five-speed automatic transmission means that victories during stoplight showdowns can be exacted over inattentive R8 drivers. Looking at our data, we can see that the Jeep launches harder than the Audi up to about 20 mph. Just brake-torque the big V8 against the five-speed slushbox, and when uncaged the Jeep drops the remaining truck pretense and heaves forward as if it had been snatched by a passing F-16.

There's no wheel-spinning drama, only the bellow of the big-cube pushrod V8 as it smashes the SRT8 toward the horizon. Four Goodyear run-flat tires endow the Jeep with plenty of traction, and 60 mph falls in just 4.7 seconds followed by a quarter-mile sprint in 13.4 seconds at 102.3 mph.

Even though the Jeep is easier to drive fast around town, the R8 still makes the numbers that count.

Here is the Video LOL watch around 1 min 3 seconds..watch how this moron launches the jeep.. omg

http://www.insideline.com/audi/r8/2008/comparison-test-2008-audi-r8-vs-2007-jeep-grand-cherokee-srt8.html

dyno sheets here

http://www.insideline.com/audi/r8/2008/comparison-test-2008-audi-r8-vs-2007-jeep-grand-cherokee-srt8.html

found this amazing article but for a R8 vs jeep srt8.. r8 has same motor as rs4 check it out

On the Dyno
With 420 hp at its command, the output of Jeep's 6.1-liter pushrod V8 matches that of the direct-injection 4.2-liter DOHC V8 in the R8. To help reveal the different personalities of these engines, we ran both car and SUV on a DTS all-wheel-drive chassis dyno.

First, the Audi spun the rollers to the tune of 339 hp, demonstrating a nicely flat torque curve that peaked at 277 pound-feet. Then the Jeep belted out 373 hp and 360 lb-ft. Pick a point anywhere in the Jeep V8's rev range and you'll find it generates more torque than the Audi, but this pushrod V8 hits the wall at 6,300 rpm whereas the Audi pulls all the way to 7,900 rpm. This higher-revving nature lets the Audi take better advantage of gearing.

What stands out most is the difference in peak power. Both V8s are connected to similar all-wheel-drive systems, so driveline losses should be roughly similar. And since both engines are claimed to generate the same power at the flywheel, they should put down very close to the same power as measured at the wheels. Yet the Jeep threw down a full 34-hp more than the Audi, so what's going on here?

One conclusion might be that either the Jeep's output is underrated by the factory or the Audi is overrated, or some combination of the two. Another theory is that the high-compression Audi V8 is more sensitive to fuel octane than the relatively understressed Jeep engine, and the crummy 91-octane fuel here in California affected the Audi's output more than the Jeep's

even the r8 dynod 34 whp less than srt8 . maybe our cars are under rated?

2cnd part i thought was interesting..

Straight-Line Performance
The R8's dash to 60 mph in 4.2 seconds and its run through the quarter-mile in 12.7 seconds at 110.7 mph demonstrates that license-incinerating performance and a calm disposition can coexist peacefully.

However, the Jeep's five-speed automatic transmission means that victories during stoplight showdowns can be exacted over inattentive R8 drivers. Looking at our data, we can see that the Jeep launches harder than the Audi up to about 20 mph. Just brake-torque the big V8 against the five-speed slushbox, and when uncaged the Jeep drops the remaining truck pretense and heaves forward as if it had been snatched by a passing F-16.

There's no wheel-spinning drama, only the bellow of the big-cube pushrod V8 as it smashes the SRT8 toward the horizon. Four Goodyear run-flat tires endow the Jeep with plenty of traction, and 60 mph falls in just 4.7 seconds followed by a quarter-mile sprint in 13.4 seconds at 102.3 mph.

Even though the Jeep is easier to drive fast around town, the R8 still makes the numbers that count.

Here is the Video LOL watch around 1 min 3 seconds..watch how this moron launches the jeep.. omg

http://www.insideline.com/audi/r8/2008/comparison-test-2008-audi-r8-vs-2007-jeep-grand-cherokee-srt8.html

dyno sheets here

http://www.insideline.com/audi/r8/2008/comparison-test-2008-audi-r8-vs-2007-jeep-grand-cherokee-srt8.html

Doesnt the R8 weight like 1000 lbs less than the Jeep? It better run a few ticks faster if its rated at the same hp!! lol
Good write up though. Interesting numbers for sure.

Thanks for the info!

I bet they over rated the hell out of those things.... Its a sports car.... period. They sell more units if they have higher HP ratings... everyone knows that...

And besides.... We can run 12.7 with an intake, catback, and tune... maybe an underdrive pully + Bbill Valve body for those who arent masters at tweaking their tune... cough cough (Wade :p)
And we have full size 5000lbs Jeeps

Srt-8 FTMFW!!!

IMO I would MUCH rather get the new GTR or 2009+CTS-V! These are the cars that should be compared to the R8... but then it wouldnt be a competition now would it? :D

Wow... someone actually took the time to compare a R8 to a SRT8? Come on.... And to the OP... don't worry what your numbers are. Your doin it right and getting a comparison between mods on the same dyno. The real numbers are at the track.

I like how in the video near the end he says that "few rational people would call the jeep beautiful"......hahahaha I guess we all are irrational then. :p

I don't know how they were trying to launch that jeep but it was ugly for sure.

thx bros..i am not worried BUT seeing that most members dyno aproc 335-350 whp stock i got abit nevouse when i saw a car with same crank hp dyno 290 whp LOL..
did anyone see the video how the guy took off in the jeep? wtf was that :eek:

Did I hear a cough-LOL

On a AW DYNOJET bone stock i dynoed 341 hp and 352 tq. Tune now is in sig.

what gear should he dyno the jeep in btw

what gear should he dyno the jeep in btw

4th for a true 1:1 ratio

Tailspin, did you ever get the baseline done? I need to get my rig on the rollers care to pass on the shop info.
Thanks

Fred

Pick and chose your races. With you being stock and with his mods i would race him in the 1/8 mile only. A races isnt that important to go in hock for thats for dam sure. Just race him stock and if he beats you its no disgrace as hes 1500 lbs lighter and will have 55 more hp. Think of it this way what if he had a Z06 VETT would you go out and spend 7000 buxs for a supercharger? Just tell him ill run you 1/8 mile only from a dead stop none of that rolling bs.

magnus motorsports.. prob tonight keel and hgwy 7 .. maybe if u come we can get a better deal

Hmmm..... My wifes gonna kill me if I leave again tonight. With Olympic hockey, I haven't been home to much lately. What time you goin? I'm gonna see how long it will take me to get there.

pushed off to sometime next week pm me ill give u my cell we can go when its good for both of us
u stock?

Ya man, I'm definitly up for this. I'll pm you my cell.

Fred