throttle body - PeachParts Mercedes-Benz Forum

JUNAID786 · #1 07-21-2011, 05:10 AM

hi

what size is the standard throttle body on the 190E 2.0?

the places i search online seem to have the same size even up to the 300E.

What is the size?

im asking coz i can get a 100mm throttle body for very cheap

Dearlove · #2 07-23-2011, 11:07 AM

dont know the size, but im will to bet its no way near 100mm, in fact, that'd be waaaaay to big for a 2.0l

remotemark · #3 07-25-2011, 03:06 PM

What would be an acceptable upgrade in throttle body size for an M103? Is putting in a larger one an upgrade at all? The concept of bigger body = more fuel makes a certain logical sense, but does it make a difference?

Chlippo · #4 07-25-2011, 07:21 PM

there is already enough fuel on a M103 and more wont do any good unless you get also some more air go into the engine to burn that extra fuel! so unless you do both and you trick the ecu to pull some timing...its worthless.

personnaly i wouldnt do it...i cant see any gains of a larger throttle body on a m103..

duxthe1 · #5 07-25-2011, 07:51 PM

I went from 64mm to 70mm. I had also done some head work, a larger exhaust and a dual snorkel air cleaner. In that trim it did make a noticable improvement from 3500 to redline. I doubt that the 70mm T/B would have made much difference by itself.

FWIW, I had to open up the intake manifold to accept the 70mm T/B. On the 103, 70mm is prety much the upper limit of what you can bolt on and have enough mating surface to seal to.

JayRash · #6 07-25-2011, 08:39 PM

duxthe1 y do u have ur cam advanced 3 deg!!! did u try retarding 3 deg?

Mike D · #7 07-25-2011, 09:03 PM

Throttle body size has nothing to do with fuel. It is air control. Over sizing the TB will actually cause problems at idle and low end speeds. Not sure if your system uses a MAP sensor but if it does you'll be jacking with it. You'll have a lower idle MAP and the system will attempt to compensate for it by adding fuel. O2 sensors work on the amount of oxygen present in the exhaust. The ECU says,"Too much O2? Add fuel to even the burn". At about 2500 RPMs you will notice a slight performance boost as you now have sufficient flow to overcome the lowered MAP reading.

I doubt any increase over 10% (going to a 70mm from a 64mm would be max) will do any good without seriously improving the flow characteristics of your engine, i.e., port the heads, increase the ignition and cam timing, air feed, exhaust, etc.

duxthe1 · #8 07-25-2011, 11:17 PM

At the risk of hijaking the thread.... I run the cam advanced b/c my 103 resides in a heavy AWD wagon and needs all the help it can get down low to get the thing off the line. Knowing that I was planning to hang a turbo I also wanted to get the exhaust valve closed sooner. In fact some of my cyl head mods were also aimed at shortening the effective exhaust duration, again with boost in mind. This car is a daily driver and I'm gearing my mods towards a strong usable power band. I want "area under the curve", peak HP doesn't interest me near as much.

JayRash · #9 07-26-2011, 05:00 AM

yes i just realized i have asked u this before. over to ur thread then

400Eric · #10 07-26-2011, 08:44 AM

Quote:

Originally Posted by duxthe1

I went from 64mm to 70mm. I had also done some head work, a larger exhaust and a dual snorkel air cleaner. In that trim it did make a noticable improvement from 3500 to redline. I doubt that the 70mm T/B would have made much difference by itself.

FWIW, I had to open up the intake manifold to accept the 70mm T/B. On the 103, 70mm is prety much the upper limit of what you can bolt on and have enough mating surface to seal to.

What did you pull that T/B off of? In other words, what is the original equipment application of that 70mm T/B? In other words, what cars can they be pulled from at the U-Pull-Its? I'm thinking CIS-E M104s? I'm hoping that there are other applications too as CIS-E M104s are hard to come by at the yards.

I'm asking here in this thread as this is the T/B thread and it would likely be of interest to the O/P as well. Thanks.
Regards, Eric

duxthe1 · #11 07-26-2011, 01:43 PM

I fabricated the 70mm T/B from a stock piece using the 70mm blade from an E400 throttle actuator. I have a few pics of it in my photo gallery.

remotemark · #12 07-26-2011, 08:31 PM

Quote:

Originally Posted by Mike D

Throttle body size has nothing to do with fuel. It is air control. Over sizing the TB will actually cause problems at idle and low end speeds. Not sure if your system uses a MAP sensor but if it does you'll be jacking with it. You'll have a lower idle MAP and the system will attempt to compensate for it by adding fuel. O2 sensors work on the amount of oxygen present in the exhaust. The ECU says,"Too much O2? Add fuel to even the burn". At about 2500 RPMs you will notice a slight performance boost as you now have sufficient flow to overcome the lowered MAP reading.

I doubt any increase over 10% (going to a 70mm from a 64mm would be max) will do any good without seriously improving the flow characteristics of your engine, i.e., port the heads, increase the ignition and cam timing, air feed, exhaust, etc.

When I have my turbos adding air and the additional injectors adding fuel, that should provide enough "food" for a larger throttle body, no?

Mike D · #13 07-26-2011, 08:36 PM

Well, you'll be increasing the input but you still have to flow it out. If you are adding dual turbos then you will gain when the second one spins but you will be losing at the bottom and low cruise speed. It's your car and your money.