Mercedes: ML 320, eaton corp, disk brakes

Question
QUESTION: I am pulling a boat with my 2001 ML320. What can I do to get a HP boost to help in pulling the boat?

Thanks

ANSWER: Harry,
How much does the Boat weigh? What is the horse power rating on your engine. Is this an automatic or strait drive?
Rob

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QUESTION: The ML is AWD and has towing capacity of 5000lbs. The boat is 4200lbs dry. with engines I am at maximum. Not sure on the HP rating but it is the V6 3.2 litre engine by MB. Is there a boost kit or something to boost HP ~ 10%?

Thanks

ANSWER: Harry,
Sorry to say that your are at the max for a couple of reasons. As you know marketing is part of the selling. 5000 capacity, is for short term short haul and probably low profile loads. Of course the dealer would not bring to light the idea of wind resistance or CG of the trailer etc. It is rather self limiting as you have already discovered.
In fact, even if you could boost the performance on the six pack, in marginal wind conditions, it could become the tail walking the Dawg.. and how about stopping capacity in an emergency. You should certainly have trailer brakes on the boat with this combination.
I would have much rather say, cut an opening in the hood and install a roots blower.... ;-)) but the expense may not offset the gain...
Good Luck
Let me know if you have additional questions.
Rob



---------- FOLLOW-UP ----------

QUESTION: Yes I figured as much. The trailer has disk brakes and I have towed this boat 800miles for 14 hours already. Pulls very well at speeds up to 70 mph. I was thinking air but not a blower as I am an Eaton Corp employee and that is one of the products we make. I may check to see if the have a street version for this engine or was wondering if I went to one of these new air filters of the lesss restricting kind??

Answer
Its difficult to say about the less restricting air filter. One would think that more air in would allow for more fuel burn. However, because the map sensor has been tuned for all around driving, it may just compensate for the different air flow and cut back on the paramaters.
You may want to investigate some performance enhanced computer tuning like use in racing. I would check with some of the racing sites or forums to see if some one has tweaked the software that may allow you to change the torque curve on the low end.
However, there may a be a limiting factor we have not discussed and that is the load on the automatic transmission. This may become the weak point with regard to performance.
I have a friend who owned a small Chevy truck and pulled a hot air balloon trailer. He kept getting a bad fuel pump code. After the forth pump changed under warranty, we stopped by an independent mechanic because the check engine lite came on 'again'. This time after running the codes the mechanic asked what gear we use to pull the load. Fifth was the reply. He said to use fourth because the long hauls under load in fifth were causing the computer to read wrong data. Sure enough pulling the trailer in 4th cured the fuel pump problem.. But that is another story.
Good luck
Rob