SL55/63/65/R230 AMG: Video of V12 BiTurbo Dyno - 624 rwhp
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...(although maybe you need a good
yourself)... he was merely sharing a video of his dyno run. Yeah, in a perfect world their would be wind tunnel testing with $1M+ fans blowing air through a closed hood while the car is on the dyno. But such conditions don't exist for mere enthusiasts. But everything is relative. When these cars dyno completely stock, under the same inferior conditions, they usually run in the 490-530rwhp range on a Dynojet. So picking up 100+hp and 150lbs-ft of torque through ECU/TCU tuning, airboxes and I/C upgrade is pretty impressive given the relative increase over stock.BTW, SGC is a hard core track fanatic (1/4 mile and 1 mile runs) so he will be testing the real world conditions in addition to the dyno.
Tom

.... in itself is not half as bad as being clueless and of the opinion to be an expert of a subject matter.....

Forced induction and the efficiency thereof has a huge impact on power output, hence the notion to use a dyno for before and after comparison without taking intercooler efficency into the equation is useless at best, totally misleading in all probability.
In more laymen terms for you to follow: Increasing boost increases charge air temperature, and not in a linear fashion. Pushing boost towards the limits of a compressor can raise charge air temperature to a level for which the engine controller will start pulling timing, dump fuel etc. possibly reduce boost; unlike the stock engine where intercooling is maybe of marginal benefit, for a modified engine without proper intercooling its not even possible to do a proper tune.
Its exactly this kind of ignorance that makes most tunes and tuners fail, look at a picture of an engine dyno and the gadzillion of temperature probes sticking on an engine making them look like a porcupine....
My argument is not against wheel-dyno's, just commenting on how clueless most of the people are that use them.
...(although maybe you need a good
yourself)... he was merely sharing a video of his dyno run. Yeah, in a perfect world their would be wind tunnel testing with $1M+ fans blowing air through a closed hood while the car is on the dyno. But such conditions don't exist for mere enthusiasts. But everything is relative. When these cars dyno completely stock, under the same inferior conditions, they usually run in the 490-530rwhp range on a Dynojet. So picking up 100+hp and 150lbs-ft of torque through ECU/TCU tuning, airboxes and I/C upgrade is pretty impressive given the relative increase over stock.BTW, SGC is a hard core track fanatic (1/4 mile and 1 mile runs) so he will be testing the real world conditions in addition to the dyno.
Tom

I also agree with CA55, a turbo proffessor I knew a long time ago said testing turbo cars on a rolling road was a waste of time as you can never simulate the amount of air when driving, no matter how many fans you had.

.... in itself is not half as bad as being clueless and of the opinion to be an expert of a subject matter.....

Forced induction and the efficiency thereof has a huge impact on power output, hence the notion to use a dyno for before and after comparison without taking intercooler efficency into the equation is useless at best, totally misleading in all probability.
In more laymen terms for you to follow: Increasing boost increases charge air temperature, and not in a linear fashion. Pushing boost towards the limits of a compressor can raise charge air temperature to a level for which the engine controller will start pulling timing, dump fuel etc. possibly reduce boost; unlike the stock engine where intercooling is maybe of marginal benefit, for a modified engine without proper intercooling its not even possible to do a proper tune.
Its exactly this kind of ignorance that makes most tunes and tuners fail, look at a picture of an engine dyno and the gadzillion of temperature probes sticking on an engine making them look like a porcupine....
My argument is not against wheel-dyno's, just commenting on how clueless most of the people are that use them.

Okay..now here is a lesson in reality...a single dyno run even with puny fans hitting the front mounted heat exchanger will not heat the intercoolers significantly. I have touched my intercooler cores after a dyno run and they were cool to the touch. The 65s do not produce large amounts of boost for a prolonged periods of time. You can try this for yourself. Now in a different application with 30+lbs of boost...yeah you have a valid point. But your condescending tone and arrogance took you out of your depths... now run along...and play idiot savant somewhere else..

Tom
Tom

Okay..now here is a lesson in reality...a single dyno run even with puny fans hitting the front mounted heat exchanger will not heat the intercoolers significantly. I have touched my intercooler cores after a dyno run and they were cool to the touch. The 65s do not produce large amounts of boost for a prolonged periods of time. You can try this for yourself. Now in a different application with 30+lbs of boost...yeah you have a valid point. But your condescending tone and arrogance took you out of your depths... now run along...and play idiot savant somewhere else..

Tom
Tom
contradicted yourself. You said 65s do not produce large amounts of boost for prolonged periods of time, that's a bit vague
I thought you once posted a figure for the 65 between 19-21 lbs of boost stock and it depends how long and how hard you drive to get a time period,, surely to get624 rwhp the boost must be considerably higher maybe 30lbs in which case
you said he has a valid point.It would be better to fit a heat sensor to your intercoolers, rather relying on touch.
contradicted yourself. You said 65s do not produce large amounts of boost for prolonged periods of time, that's a bit vague
I thought you once posted a figure for the 65 between 19-21 lbs of boost stock and it depends how long and how hard you drive to get a time period,, surely to get624 rwhp the boost must be considerably higher maybe 30lbs in which case
you said he has a valid point.It would be better to fit a heat sensor to your intercoolers, rather relying on touch.

https://mbworld.org/forums/3922090-post15.html
You try to simulate "rolling" conditions as best as you can on a dyno run. I usually run with 3 fans that can run up to about 45mph (10000 CFM each) pointed directly at the HE with the hood open. Take a look at the CL's hood when it is closed. It is not the most efficient design to flow lots of air volume. The open hood also allows better heat dissipation than with the hood down.
I usually run the dyno in 3rd gear which goes from about 50mph to about 118mph. The car is under boost for about 10 seconds in total. It is probably making maximum boost for about a second or two based on the data logging done out on the highway. It kind of spikes and then significantly tapers off. I can data log the IATs next time I am on the dyno and then compare that to doing the same run in 3rd gear out on the road.
Tom

.... in itself is not half as bad as being clueless and of the opinion to be an expert of a subject matter.....

Forced induction and the efficiency thereof has a huge impact on power output, hence the notion to use a dyno for before and after comparison without taking intercooler efficency into the equation is useless at best, totally misleading in all probability.
In more laymen terms for you to follow: Increasing boost increases charge air temperature, and not in a linear fashion. Pushing boost towards the limits of a compressor can raise charge air temperature to a level for which the engine controller will start pulling timing, dump fuel etc. possibly reduce boost; unlike the stock engine where intercooling is maybe of marginal benefit, for a modified engine without proper intercooling its not even possible to do a proper tune.
Its exactly this kind of ignorance that makes most tunes and tuners fail, look at a picture of an engine dyno and the gadzillion of temperature probes sticking on an engine making them look like a porcupine....
My argument is not against wheel-dyno's, just commenting on how clueless most of the people are that use them.
https://mbworld.org/forums/3922090-post15.html
You try to simulate "rolling" conditions as best as you can on a dyno run. I usually run with 3 fans that can run up to about 45mph (10000 CFM each) pointed directly at the HE with the hood open. Take a look at the CL's hood when it is closed. It is not the most efficient design to flow lots of air volume. The open hood also allows better heat dissipation than with the hood down.
I usually run the dyno in 3rd gear which goes from about 50mph to about 118mph. The car is under boost for about 10 seconds in total. It is probably making maximum boost for about a second or two based on the data logging done out on the highway. It kind of spikes and then significantly tapers off. I can data log the IATs next time I am on the dyno and then compare that to doing the same run in 3rd gear out on the road.
Tom
What is standard boost on a CL65?
I am not sure what data logging tool he is using. I think I got around 18psi stock...around 1.2+ bar using my friend Jay's data logger.
Tom




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