are these BTB 80mm or the 76mm each?can we use the 550 tb`s?will the housing be the same?

 

BBTBs are usually extreme overkill on NA AMG engines and are the LAST mod you should ever do. There are so many more bottlenecks choking off the engine long before you get to throttle bodies and are usually one of the lowest HP/$ ratios when it comes to NA cars.

You can pick up 100HP on the C63s without even touching BBTBs. Unless you are getting close to the 600s, its honestly a waste of time and money. Even so, typically the gains are usually only in the last 1000-2000rpm of the power band (at most).

most of the bottlenecks on most AMGs are in the exhaust system (specifically the front half of the exhaust system), that's always where you pick up the most power. The intake side of the engine is so well engineered from AMG that its extremely difficult to pick up any substantial power there (usually air filters upgrades are all you need to do, even kompressor AMG airboxes are proving to not make much power if any at all).

just telling it like it is.....

 

I was hoping that the bigger throttle bodies would at least make a difference on a heavily modified car, such as Keith's.

 

Since you bring up the air filter issue, do you think BMC or K and N make a difference? I've heard both sides, so what's your take? Thanks..

 

A BIG +1

On a NA engine, which ALREADY has an over kill capacity in CFM, you will NOT see any difference. Comparing apples to apples. That is allow BOTH of them to open 100% and then dyno, you will not see squat.

Back in the days, aka early 90's, the stock mustangs had a 60mm TB, EVERYONE jumped on the Motorsports bandwagon and bought the 65mm TB, which promised a "Substantial Horsepower increase". Reality at the track drag and road race, NOTHING.

Start at the Worst place first, aka exhaust manifolds the biggest choke point, and keep going from there.

I have used both, and like both. The difference between them is often price Sometimes one or the other will have a uniquie fitment so you have NO choice.

The performance difference is NOT detectable on a dyno.

 

my gut tells me the exact same thing which is one of the reasons I am so interested to see data if someone is going to do them anyway.......

 

Guys if i went with the MHP LT headers with the ECU TCU tune would it be ok if I added the kleemann throttle body and the Evo Sport pulley, Or should I stick to MHP??

 

I would stick with the MHP products. Nothing wrong with the kleeman throttle body but there is no supporting data that there is an advantage to have them and they are VERY expensive.

 

renntech just released their C74 package, and i believe they also have bigger TB's in that package as well, just like kleemann, so if both tuners are doing it, i would say the TB's do give the car some HP or TQ, but due to the price not much people have jumped on this mod for our cars

 

i like ur reasoning...

 

Gentlemen, sorry to revive such an old thread but this one is the first one that came on my search and seems close to my issue. I recently purchased a used 2011 C63 (less than two months ago). I bought it from a dealer in Georgia but the car was originally purchased and titled in New York. I do not know who the previous owner was.


the first thing I noticed was that the car had the full akrapovic exhaust on it. I suspected the car had other mods, but nothing I could tell. This is my first time owning a C63 so I cannot compare to others to know how different this one is. Recently (last week) I got a CEL and after dealer diagnosing, seemed to be the throttle cable assembly. Well today I found out, the car has larger throttle bodies installed. They look identical to the OEM one except the bigger orifice of the body, seems to be around 8-10mm bigger at a visual inspection. The part number is the one used on the Porsche 997, part number 997 605 116 01 and references to Bosch part number 0 280 750 473. The OEM TB part number is AMG A 156 141 02 25 and references to Bosch part number 0 280 750 246. Only one failed, the motor inside of it so I am purchasing the replacement aftermarket TB to keep the current setup.


Question is, without knowing the previous owner and what he/she did to the car, I am trying to do some investigative work to find out who may have done the work. Both Kleemann and Renntech are closed and will have to wait until Monday. Maybe someone here has knowledge of the use of these Porsche parts on our cars as to who does that type of modification. I know for sure it has a custom tune now based on the items found on the car so far. Thank you.

 

Talk about an old bump, it's my turn now!

Been doing some research on these larger throttle bodies. I know it's not a big gain, especially for the cost. HOWEVER, these larger Bosch 82mm throttle bodies retail for about $200 each. And the electrical connections all look the same. So I'm kinda thinking about ordering a couple and seeing if I can take them apart and retrofit into my intake manifold. You know, just for giggles.

Has anyone else looked into this? The Kleemann and Renntech prices are outrageous, especially since these parts are so cheap. Where's the $ go - is it machining, or coding, or what? It looks like a new plate would need to be made to hold the new TBs, or the existing one modified - how hard can that be? It's cheap enough that I might just get a couple and see what's up......

Conv_GSDriver (if you're reading this) did you just buy the replacement Bosch unit and it bolted right up?

 

I have the 80mm kleeman set I took on trade. I put them in after putting a tune in from OE. The engine actually ran a little rich until I installed an updated map. No dyno yet but I do feel a little more throttle response and feels like more pull at the top. Go to fleabay and type m156 throlle. There's a guy selling 82mm adapter plates for $800 obo.

 

I actually attempted this myself a few months back. Didn't work out to plan, so i've put it on the backburner for now. Some tips for you:

* Modifying the existing throttle plate is...for all intents and purposes, going to be a monumental bodge. However, nobody will see it, so as long as you seal it, it's all good.
* You'll have to grind away material in loads of places in order to let the throttle bodies sit into the housing. A die grinder or air powered hand held sander is your friend.
* To secure the throttle bodies to the plate, you can use one oem bolt for each of them - the rest you'll need to drill right now through the plate and use a long bolt with a nut.
* No gaskets here....you'll need to use epoxy (JB Weld or otherwise) to seal the throttle bodies (i also sealed the nuts in place too....don't want those getting sucked into the engine!). At some points of the throttle plate, after you're done with grinding away to make the entry holes big enough, you're left with less than half a mm of space to 'seat' the throttle bodies on, so getting a good seal with the epoxy is crucial.
* These Bosch throttle bodies don't have the nipples on them for the two black idle vacuum hoses
* THEN...(as if that wasn't bad enough) the angle of the throttle plates are opposite to the stock throttle bodies. So even if you want to have a nipple specially fitted (use any method you like, but i had a nipple screwed in and tapped into the throttle bodies on the opposite side) - you can't have the nipples added to the oem throttle body location because of the angle of the throttle plate
* THEN....space is so tight for your vacuum hoses to be routed around and connected back up to the oem black idle hoses....I was losing hope for my install at this point, and just used any old fittings that I could find from my local shop...at this point, i just wanted the damn thing to work.

When it came down to the install day...urgh, i was pissed. In short, it didn't work. Car cut out right after firing it up. If it was able to maintain something of an idle, it still chocked out and cut out. Wouldn't respond to throttle at the pedal, ie was in limp mode. I called Mercedes to come and scan the car on my driveway and it was unhappy with something to do with the TPS or something..I can't remember the exact codes. I think (don't quote me on this) the Bosch throttle bodies open in the opposite direction to the stock ones. If that's the case, maybe it physically won't open because of software etc really don't know

In short....probably not worth doing this ^


However, if it helps...there's a guy in Russia on eBay that sells used throttle bodies along with a custom adaptor plate, which probably does work on our cars, but after having wasted money on my attempt and my cars power mystery, I haven't bought them from him yet. Maybe you can be the test muel?
http://www.ebay.co.uk/itm/M156-Engin...MAAOSw2GlXKopH

Good luck

 

Awesome insight mate, exactly what I was hoping someone had direct experience with. Thanks!

Think my first step is to look into the machined adapter plate, because that seems like the part that could cause the most trouble (modifying the existing one seems like it could result in either JBWeld or nuts getting ingested into the engine which would be no bueno).

Will report back if I find anything new, but I'm not optimistic about it especially given the difference in operation of the bigger TBs. I remember seeing a detailed post on a U.K. website some time ago on these Porsche/Bosch TBs but have to dig it up to see what the solution was.....

 

BLK,

The adapter plates for the 82MM TB's are available online. Where can we find the 82 MM TB's for $200 a pop?

PS: I have the renntech TB's in my car, they made almost 10 wheel compared to the stock setup. The throttle response is super quick though. I love it.

 

You can see what i meant about the throttle plates being at a different angle and how tight the fit is with these pics.











I'm sure that there must be a slight variation to these throttle bodies which would make them suitable for our engines...seems like Renntech and even the guy in Russia know something that we don't.



Kriston, where is this plate available please, or are you referring to the guy in Russia? Funnily enough his plate looks the same as the Kleemann one i think.

I want that razor sharp throttle response too. My M5 and Celica have wayyy sharper throttle response and as a result, are more exciting to drive, regardless of speed.

Here's where I bought my throttle bodies from (I think):
http://www.onlinecarparts.co.uk/bosch-686155.html

 

The car had that already installed, found out after I started getting the CELs. Seems the previous owner did a stage 1 install with the TB kit. I did call both Renntech and Kleemann and provided them with the car's VIN but to no avail. According to both places, they do not use the car's VIN to track what they have done. But it looked very much like the stage 1 setup from Renntech.


To answer your question, I did buy the replacement part, the non-OEM one, and it dropped right in. The OEM one is the same overall diameter, they look exactly the same, the only difference visually is the opening itself. That is how the dealer was able to tell I had bigger TBs. Once they replaced the bad one with the OEM one, the openings for both were different sizes, that's when they called me and told me of the situation. I suspected the car had something else done to it and this confirmed it, chances are it also had a tune.


The housing for both TBs was the OEM one. What I am unsure is the wiring and plugs. I think it's pretty much a plug and play one.

 

I ended up referencing the part number on ebay (both Mercedes and Bosch) and they came up. You will find them ranging from $190 to $230 depending on the vendor. Look in the listing as some are new while others are refurbished. I'm pretty sure I can find the vendor I got mine from if you need it.

 

This is interesting. Subbed for updates.

 

I'm guessing what you read about is what I discovered over the weekend.

So....I wanted to work out why the throttle bodies didn't work last time round when i fitted them. This time, i connected the bigger throttle bodies via the hardness (intake manifold removed) and then turned the ignition key to position 2. SO....lol the car opens them fully with 0% throttle applied.....the car closes the throttle at 100% throttle applied - ie, it's working in reverse.

I need to find a way to reverse the signal, or just give up on these and try to buy either a TB from a 997 Porsche (not sure how much difference it'll make, but might be worth a stab if you think it's got a slight difference to the Bosch ones I've got), or I'll just have to bend over and buy the set from the guy in Russia and then be a nice person and post the part numbers if they're still stamped onto the units.

I'm in the process of hacking one of the TB's up to reverse the signal it takes at the motor. If that doesn't work...it's safe to say that ordering these throttle bodies and trying to make them work, doesn't work.

 

Interesting. It's a two-wire connection to the TB motor if I recall correctly. I wonder if it's as easy as reversing those wires?

 

Yeah that's exactly what I attempted on Saturday, but it'll maybe require a bit of creativity with the dremel to chop n bodge a plastic holder that was only ever intended to fit in a particular way.

I managed to flip them, but the fit wasn't good and it was pressing against the motor, making it impossible to close (by naturally rotating backwards under spring pressure), once the ecu makes them to the initial blip open for the heroic engine sound when the motor fires etc.

I'll report back once I've either failed or succeeded.

 

Let's hope you succeed then. If it works for you, it paves the way for the rest of us.
Good luck.

 

The other thing to consider is looking at reversing the signal to get the throttle plate to rotate the opposite direction. It's been awhile since I had one apart, but I don't think it's exactly that simple - I think there are either 'stoppers' cast into the pivot body, or another mechanical reason why it can't be done. Might have to flip the throttle plate, which is probably also easier said than done. I think that's too easy (or dumb) an answer.... worth looking at maybe?