Dyno Results For SpeedTuning USA Chip
MBWorld Fanatic!
Joined: Apr 2005
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From: SCV SoCal
2002 CLK430
I suppose there's some room here for a difference of opinion. If I am modifying my motor with the hopes of generating more HP, then doesn't it stand to reason to remove as much of the other factors as possible? Whereas, if I want to know what my "total modification" power looks like - including driveline - then I'd want the wheels on. We rely on factory numbers that are measured at the crank as the baseline from which measure, don't we?
Alternatively, you can do a baseline quarter mile run and record the trap speed. Forget about the ET. Do another couple of runs after the mod. The MPH figure is directly proportional to the HP AND the trap speed will be lower for peaky mods. The trap speed was what we used to use in the 1970's before dynos were affordable and available all over southern California.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 9,155
Likes: 20
From: Southern, CA.
V12-Biturbo
If you want to know the results of a mod, the *best* way that I know of is to get a baseline dyno before the mod, and then another after the mod - on the same dyno. That's why some people have STACKS of dynos on their cars. They're keeping track of what works, and what doesn't. Also, a spike is worthless if the numbers are low everywhere else. This is not as uncommon as many might think. I've had exhausts that were the *quintessence* of this. No power anywhere except a narrow range on top when BANG the HP figure spikes for all of a 600 RPM range.
Alternatively, you can do a baseline quarter mile run and record the trap speed. Forget about the ET. Do another couple of runs after the mod. The MPH figure is directly proportional to the HP AND the trap speed will be lower for peaky mods. The trap speed was what we used to use in the 1970's before dynos were affordable and available all over southern California.
Alternatively, you can do a baseline quarter mile run and record the trap speed. Forget about the ET. Do another couple of runs after the mod. The MPH figure is directly proportional to the HP AND the trap speed will be lower for peaky mods. The trap speed was what we used to use in the 1970's before dynos were affordable and available all over southern California.
MBWorld Fanatic!
Joined: Feb 2004
Posts: 9,155
Likes: 20
From: Southern, CA.
V12-Biturbo
The 364.3 HP to the crank is derived from multiplying the 303 rwhp by 0.20, which represents 20% more hp to the crank as a result of drive train loss of HP to the wheels. This is of course an estimate but 20% seems to be what the industry recommends as a accurate figure for drive train loss. Plug any percentage for drive train loss and the HP goes up and down to the crank.
The Porsche guys typically use a figure of 16% (0.16) for drive train loss, since the engine is right over the rear wheels. However, I used 20% to be more generous for my cousin's Carrera S.
As a side note, the amount of exhaust pressure is pushed out of the car at around 5,000 RPM is incredible. I only noticed while holding the A/F sensor since it wouldn't insert into my oval exhaust tubs. Had to use welding gloves so as not be burned.
What does your Vet put down to the wheels? Is it the 400 HP and 400 TQ engine?
The Porsche guys typically use a figure of 16% (0.16) for drive train loss, since the engine is right over the rear wheels. However, I used 20% to be more generous for my cousin's Carrera S.
As a side note, the amount of exhaust pressure is pushed out of the car at around 5,000 RPM is incredible. I only noticed while holding the A/F sensor since it wouldn't insert into my oval exhaust tubs. Had to use welding gloves so as not be burned.
What does your Vet put down to the wheels? Is it the 400 HP and 400 TQ engine?
Well over 400 @ the crank now..
The only problem I see w/testing it out on the 1/4 mile is the same if you say went for an Auto X day, you wreck it, or someone else runs into you, NO Insurance, kaput you are **** outta luck so what to do
So I have always street raced a friend pre-post mods to see what works or doesn't
yes stupid but what are my alternatives giving Ins. regulations? yes I know if they could proove I was street racing I'd most likely be droped but feel at least I have a chance compared to running on a track. 
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Joined: Feb 2004
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From: City with Tall buildings!
C43/55,2k11 Volvo S60 T6AWD,2k Audi B5 S4,95 Eagle Talon Tsi AWD 500+awhp
Just use a dynojet and be done imop. Simple. I have dynoed my car on a dynojet several times with no complaints. My car has dynoed in 3rd gear no probs,4th no probs,5th no probs with the ABS harness disconnected. Whatever #'s you get use them as baseline to see what improvements you get with your mods.
Or you can ask Chappy how he got his #'s. Same goes for PTE and his CLK55. We've all used dynojets.
Or you can ask Chappy how he got his #'s. Same goes for PTE and his CLK55. We've all used dynojets.
Thread Starter
Senior Member
Joined: Aug 2005
Posts: 453
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From: Las Vegas
2005 SL600 by SPEEDRIVEN
Chappy's car downshifted and he wasn't able to shut-off the ESP. This is a problem for our cars.
I think I asked this before but does your conversion car have the ESP system, because it doesn't sound the same as our system? Disconnecting the ABS, BAS or ESP causes computer system errors and power loss to protect the car.
I think I asked this before but does your conversion car have the ESP system, because it doesn't sound the same as our system? Disconnecting the ABS, BAS or ESP causes computer system errors and power loss to protect the car.
Last edited by ashutt; Apr 27, 2007 at 01:17 PM.
Thread Starter
Senior Member
Joined: Aug 2005
Posts: 453
Likes: 0
From: Las Vegas
2005 SL600 by SPEEDRIVEN
It does have the manual shifting but that didn't stop the ECU from downshifting under load. How did you turn off your ESP? That also wanted to kick in even when turned off from inside the car.
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MBWorld Fanatic!
Joined: Feb 2004
Posts: 5,475
Likes: 5
From: City with Tall buildings!
C43/55,2k11 Volvo S60 T6AWD,2k Audi B5 S4,95 Eagle Talon Tsi AWD 500+awhp
My car has the same ABS /BAS, ESP system as the CLK's especially a 2k1 CLK55 but no triptronic.
What the shop did with my car was manually go thru 1st gear,then 2nd gear and floored it in THIRD gear to the rev limiter and got the results! Yes with the ABS harness on. And many other times with the harness still connected to the ABS and the ESP switch off.
(The ESP light,when off, did still blink a few times in this case as well though but still put out consistant results) So Ashutt try rowing thru the gears manually from 1st to 3rd. When you get to third gear from shifting manually on the dyno gradually floor it and let the car hit the rev limiter.
The guy used the same method to go into 4th gear WOT to the rev limiter as well.
Shifted the car manually on the dyno. Then got my results.
Last edited by ProjectC55; Apr 30, 2007 at 08:14 AM.
