lxl_Jeffro_lxl

I'm not sure if it is a good idea or not, but should I install a BOV (Blow Off Valve) on my 1999 E300 TD? Because I have been reading about them and how they relieve back pressure etc. and I want a faint whistle....but doesn't it already have a device on there to stop back pressure on the turbo? Any advice would be nice thanks!

240D 3.0T

There is absolutely, positively no need for a BOV on your diesel. Your engine does not have a throttle so there is no backpressure to relieve.

It would be a waste of time, money and sound VERY out of place.

SmokinCummins

We use them on Dodge trucks which are very heavily fueled. They serve as a fuse to dump pressure in the intake or between stages of turbo. They are used to relieve pressure when you suddenly have to lift your foot under full boost or in the event of a nitrous backfire. Turbo bark can break shafts on some turbos and a BOV will help to save a turbo, or turbos.

240D 3.0T

I doubt he is running 50+psi of boost on his E300. I can see a BOV as a safety device running extreme boost levels on a twin turbo Cummins. On an E300 that runs 13psi, it's a waste of space and time.

mv420xx

thanks, ive been trying to find what my cars psi is for the longest time. as for the BOV thing, i know where ur heads at man. dont bother, for the 300 ud spend on a BOV that does nothing, get a chip for 275 and add REAL HP/TQ. and 240D knows his stuff, ive watched his posts carefully.. spend the money on a chip and have fun.

SmokinCummins

Actually, they are a waste of money on a 50psi Cummins.

lxl_Jeffro_lxl

Any suggestions on a reliable chip for my 1999 E300 TD? This would be my first motor mod, except the intake....but if I were to purchase a chip, what else would I need to modify so I don't burnout my motor

harkgar

Go to the Carlsson site. I think they do a tuning box for your W210.

240D 3.0T

I would install a pyrometer (Exhaust temperature gauge) BEFORE doing any power mods so you don't melt your pistons.

anghrist

To lxl_josh_lxl concerning tuning chips:

Yah don't need to chip these cars. That little pedal on the right works very very well.

But if you must, here's the best bang for the buck:

http://www.speedtuningusa.com/

240D 3.0T

Blow-off valves or BOV or similar

Since people insist upon asking about these devices, they need to be discussed ... The purpose of a "blow-off valve" or "diverter valve" on a gasoline engine is to give boost pressure someplace to go when the throttle plate is abruptly closed, to prevent operating the compressor in the "surge" regime. Since a diesel engine doesn't have a throttle plate, a gadget like this serves absolutely no purpose and has no business anywhere on a diesel engine. "But I like the cool noise ..." Too bad, this discussion is focused on things that WORK. Even if you manage to find some way to make such a device work, the noise of people "in the know" laughing at you because they realize that it has absolutely no place on your engine will drown out the noise that the device itself makes.

Installation: Impossible. Cannot be made to work even if you insist upon it.

Advantages: None.

Disadvantages: Won't work. People who actually know how a diesel engine works will laugh at you for even considering it. You are your own warranty.

Cost factor: Too much, all things considered.

Cautions specific to this modification: Won't accomplish anything.

Suggested modifications in parallel: Irrelevant.

"Bang for the Buck": One hundred percent total waste of time and money.

What if I want more? Do something that actually accomplishes something...

mv420xx

like i said, watch 240D's posts closely and ull learn a thing or two on this site. i do searches constintly so i dont repost the same thing that others post daily.
thanks for the clear up 240D...

anghrist

240D 3.0T,

I agree with you. I just wanted to answer a question he had about chip tuning.

The best way to get more horsepower or torque into/out of a vehicle is to install a more powerful mechanical system that is built to produce such energies and forces. Silly modifications that amount to nothing and are pointless are simply a waste of time and money.

My views on chip tuning are that it can work, but there is always a trade-off for that "extra" power. Engineers don't spend the amount of time they do trying to build something that is underpowered and inefficient.

Green E-300 DT

I kind of changed anghrists' meaning a trifle, but . . .

I did have Oliver give mine the treatment. Best $400 + I ever spent.

($275 plus overnight shipping from California and prepaid overnight return so that the car would not be tied up for too long.
Turn around, the car was only down for 46 hours!

When you talk to Oliver, make sure you ask for his most powerful "tune."
You will not be sorry you have him do your computer.

BTW, forget that tuning box treatment.
It is not as powerful as when you have Oliver change out your original factory chip.

The only drawback to having as much torque as this new chip will give you is that your
right rear tire will not last as long if you are not careful coming out of the hole.
With all that additional torque, it's hard to launch without wheel spin.

240D 3.0T

True but they must also conform to emissions limits and durability goals.

They could easily make the 07 CDI's have 350hp but they wouldn't pass emissions in any state and probably wouldn't last more than 100-150k miles.

anghrist

Do you forsee any negative impacts, other than worn tires due to this (chip) tuning modification? I'm very concerned about the mechanical life expectancy of the engine and transmission. I tend to take off slowly to avoid long term issues and only let the hounds loose when I've picked up momentum. I like the idea of more horsepower, but most of my driving is freeway cruising which doesn't require a great deal of energy. Towing may be an issue later though. Then I may want some more low end uumph.

Green E-300 DT

The extra horsepower is not really what you are looking for.
You will see much more torque, and that is what makes it pull so much stronger.

You'll only have worn tires if you use the extra torque all of the time from rest.
I never really had any problem because I tended to drive as you discribe your driving style.

Letting the hounds loose" after you are underway is where the extra torque really shows itself.
In fact, I almost always started from rest in second gear, and allowed the trans to
upshift as early as possible to take advantage of the extra low RPM torque.
Before I had mine done, I often felt that I needed to downshift to accelerate while on the freeway,
but after Oliver modified my computer, there was no need to do that.

The car always seemed to be right in the middle of the fat torque
curve, and hence there was no need to drop a gear.
The car really pulled when I leaned on it, and it felt like it had downshifted when it actually had not.

My trans did fail, but as I couldn't make the payments, I had the lender Repo it.
The vehicle had 127K miles on it by then, so I cannot say whether or not
chipping it added to the stress enough to cause the tranny to fail.

If you should decide to have Oliver do yours, make sure that
you have clean fuel filters, and of course a fresh air filter.

BTW, mine turned 70 mph in the 1/8 mile in 10 seconds flat.
So you could say 0-70 in 10 seconds. What they will do stock I do not know.

anghrist

Starting a new thread as we have kind of hijacked this one. Not that there was much relavent to discuss concerning BOVs anyway.

anghrist

http://www.youtube.com/watch?v=jT809VeHCEU

DUH?!?!

SmokinCummins

Do you mean to say Mercedes diesel, or Diesel engines in general? They do indeed serve a purpose and do work quite well on a diesel. Compressor surge can and will destroy a turbo. I have a few turbos laying around here that grenaded from compressor surge. A BOV could have saved them.

A BOV may not serve a purpose on a Benz, but they do have a place in high performance in a diesel application. They are activated differently than a gasser (IE no throttle), but the theory is the same.

When a gasser has the throttle slammed shut, there is a dead end that should be vented. A diesel has no throttle blades, so no dead end that needs to be vented. Well right and wrong. When you back out of a diesel suddenly, there is a sudden loss of drive pressure. When this happens, the turbine looses its power to drive the turbo, but there is still all that pressure and volume built up between the compressor and the valves. With no drive pressure on the turbine, the built up air tries to escape back out the compressor. If you have ever heard a turbo "bark", this is what causes the bark - air rushing back through the compressor.

Now on a Benz, there is not much pressure or volume - especially if there is no air to air cooler. On a truck where cooler piping is 3" - 4" in diameter and a cooler is 3 foot wide and 2 foot tall - there is a huge volume of air. The higher the pressure the more force acting on that turbo. Usually, when one lets go, it is the shaft that breaks.

I am not sure what is worse, having a $2500 turbo break, or the thought of all that shrapnel being pumped into the engine while the blown turbo grinds to a halt. Another good place is when running staged turbos. If one turbo goes, it usually will wipe out the other turbo. Some guys are running BOVs between stages as well as both sides of the charge air cooler.

So to answer the question, yes they have a purpose, but not for the average diesel enthusiast.

240D 3.0T

As I said before, I very seriously doubt anyone is going to run 50+psi of boost on their MB. Even the Finnish Superturbos don't use more than 35psi to get 350hp+ out of 3L engines.

Your turbos could have been saved if not for driver abuse. Instead of abruptly letting off the accelerator, knowing the possible outcome, easing off the accelerator could have prevented it.

SmokinCummins

That is why I asked, I thought you were talking about diesel in general, not just the Benz.

As for saving a turbo by driving right, maybe in a perfect world, but in competition, anything can happen. As an example, I had my truck sideways at the dragstrip when it shifted into second. I had to lift immediately, which barked the charger hard about 5 times before it lost all the boost.

I have also had instances where I was grossing over 20,000 pounds flat to the floor on grade when I got cut off. Impossible to not bark a turbo when the unseen happens and you have to go from full fuel to on the brakes. Same thing in town - accelerating with a load and someone tries to jump out of Mcdonalds in front of me so they don't have to follow a trailer. In that case it is only part throttle, but it will still bark hard when I lift suddenly.

I am running a $1850 turbo, but these particular turbos are known for being very tough and "bark" does not affect them on fuel only trucks. NO2 is another story. I bark mine from time to time, but do not worry about it because of the reliability of my turbo. Guys that really see a problem are running the stock turbo at high boost and barking them alot, and guys running the HX40.

Right after I put the turbo on, I went to a Dyno event. This particular place ran the truck and would not let the owner run it. First pass he ran it to redline (3500rpm) and chopped the throttle. It barked twice and was unbelievably loud inside the shop. The reaction from the audience was priceless - wish I had it on video.

Ugly

If one is trying to add some boost on an e300 MB turbodiesel, is there a convenient method to measure, say with a guage readout, what change results from an/any adjustment to the wastegate?

It does not have to be a dashboard readout, whatever is easiest and does the job.

One may not even need the guage after an adjustment to the wastegate is completed, this is just to be more precise while working than: a little, some more, a lot, too much, darn broke it.