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J Irwan
09-08-2003, 07:20 PM
Jeff, or anyone else.


Do you guys know, where I can have a custom big-bore throttle body..

I am thinking of having mine enlarged..?

Also for anyone who is running underdrive pulley, what is the disadvantage of having these on electronic gadget..??

I am thinking about the underdrive pulley, but I am concerned with the possibility of it affects my sound system (as the sound system is a must on my car)


Regardz,

speedybenz
09-08-2003, 08:18 PM
Junaidi,

You might see if a C43 MAS and throttle body will fit on your car, or if they are larger. I can measure the inner diameter of the MAS for you.

If you modify your own throttle body, it will be easy to have it bored out larger but getting the throttle plate made up is difficult and then fitting it to the throttle shaft will be hard but doable.

If I were you I would look at getting you cam sprockets slotted or modified so you can adjust the cam timing. Doing this can sometimes gain 5 to 10 percent Hp.

Also Installing an electric water pump is good for a quick 10hp and may reduce the water temp also.

And if you really want to make a big change go for new cams. Don't get the Renntech stuff, it over priced and not very good, IMHO. Get some cams from Comp cams or Webcam. I can help with the details.

Jeff

Renn 208
09-08-2003, 08:29 PM
Originally posted by J Irwan


I am thinking about the underdrive pulley, but I am concerned with the possibility of it affects my sound system (as the sound system is a must on my car)



Yeah I wouldn't underdrive the alternator pulley if the system's important to you...however, you can underdrive the rest with impunity!

CKlasse
09-08-2003, 08:36 PM
BTW... I've talked to Webcam late last year after seeing their ads on one of the performance magazine. They are willing to cut their price pretty deep if you are willing to let your car be a prototype. They do require newer high performance car though. Mine was out of the picture :(

Newer C230K, 280 or AMG owners should call them.

1SIKBNZ
09-08-2003, 11:24 PM
hmmm wonder if they would take a 99 280? :D

J Irwan
09-09-2003, 01:34 PM
Jeff,

can you email me the pic of C43 throttle body..??

I want to see if all the port are on the same place as C36..

I will measure my throttle body Inside Diameter (I.D)


Also can anyone tell me if CLK55 (w208) and E55 (w210) has the same diameter TB as C43..??


Regardz,

Denlasoul
09-09-2003, 02:08 PM
Wouldnt the TB of the C43/E430/E55/CLK430/CLK55/ML430/ML55 be the same? Basically the M113 engine cars unless AMG did something to enhance the TB. I know they did the intake manifold and run hotter cams.

speedybenz
09-09-2003, 07:15 PM
Junaidi,

I will get you a pic this weekend. The E55 and such may have a larger Throttle Body as the displacement is 1200cc more. So I would think the TB is bigger.

We need to measure one up.

Jeff

Renn 208
09-09-2003, 09:30 PM
Originally posted by speedybenz
Junaidi,

I will get you a pic this weekend. The E55 and such may have a larger Throttle Body as the displacement is 1200cc more. So I would think the TB is bigger.

We need to measure one up.

Jeff

now that just begs the question...is there a part number for a CL65 throttle body and would it be huge? or...do the big V12s have a different design altogether?

Three Point 6
09-18-2003, 06:56 PM
J Irwin,

On the subject of naturally aspirated power increase for the C36, do you or anybody know the engine specs of the DTM 3.6 motors. IE; cams, flow-rates, I & E manifolding, injector sizes. It would be great to know what architecture was used on those engines as a guide for enhancement. I heard the DTM 3.6 had 400hp natural. I am all over modding the motor on my car also if a teardown is needed in a couple years when it is paid off & in the 125k mile range.

I believe 315 hp can be had w/header from Bekkers, Powerchips ECU & custom made K&N set-up?

714guy
09-18-2003, 08:53 PM
IF the 55 motor TB fits on the c36, then you could also get the Maybach one too. That kleemman c55 done by benzmac has a maybach throttle body on it, but he had to do some wiring to reverse the way it opened. on something like that.

CKlasse
09-18-2003, 10:26 PM
Not to ruin the moddin spirit...

but instead of increasing CFM and then you have to mess around with fuel mapping etc... Why not do the simplest thing of all? Increase your compression ratio from 10.2:1 to 12:1. You can simply custom order rods for less than a grand and will much better HP gain/dollar.

Another $200-500 at local machine shop to do your head, and you'll have one mean C36!

CKlasse
09-18-2003, 10:34 PM
... BTW... Bigger TB doesnt mean better torque/hp all the time. You will loose some hp & torque at lower RPM due to velocity decrease. Unless you are talking about doing your head and exhaust side. For the money, I would go for longer rods - increasing the compression by longer stroke! :)

speedybenz
09-19-2003, 09:23 AM
Ok, so you have an AMG C36 engine. First you tear it down and measure the deck ht. and piston to valve clearance, cam timing, etc.

Once apart you measure the crankshaft bearing journals. If the rod journals are bigger than a std. honda then you grind them to the smaller size and gain some stroke. The smaller bearing reduces the bearing speed and friction-more Hp.

2nd you get the wt. of all the stock piston, piston pin, rods and then go looking for something better and lighter. Same goes for the valves. Maybe you remove the stock valve guides and use new valve guides which allow valves with a smaller diameter stem to reduce wt.

3rd, you get the crank lightened and balanced. You also get it coated to shed oil better. less drag-more Hp.

4th, you get the head done. You may end up making the intake ports smaller, bgut with a better shape and since the valve stem is smaller you get more flow.

New cams with duration about the same as stock but with faster opening ramps. You have valve that weigh less so you can open them up faster to get more air in the motor.

Set your deck ht to .030" to take advantage of your new rods and batter pistons. Piston have total seal upper rings for near zero leakdown.

Custom header.

Slap it all together, set the cam timing to 105 LC on the intake and 110 Lc on the exhaust.

Now you have a 400hp motor.

Jeff

CKlasse
09-19-2003, 03:04 PM
What kind of coating do you use for the crank? I always thought you can have a hotrodder to machine a better oil groove on the bearings themselves.

Although I am not by any mean an expert engine builder (In fact, I have only done two in my life), at the shop I found out that many german block decks are warped.

From my own experience with the 2.2L of the C Class, I found all cylinders are tappered (Does it mean it has very good rings? minal leakage?), and the piston skirt are longer than usual. Also, the crankshaft ring are very thin compare to other german bottom ends. I wish Merc would use 'craddle' as in Mitsubishi 3.0L.

I dont have any experience to relobe the cam, but I am going to be using lighter forged valves and dual t springs instead. And at 84000 miles, the cam clearance and crank journal clearance are amazingly still within spec.

Here is a trick that I learnt recently, thread the valve guide (groovy baby!), then machine the surface back to smooth. These grooves will retain oil much better.

Furthermore, I have seen JE forged pistons as thin as 1/2" below the oil ring. I am not sure how much vibration these thin pistons would cause. JE also provides piston rings per your specs. I have had unpleasant experience with JE customer service in the past, but I think I am going to go for them once again.

I am learning so much for the past couple months. I cannot wait til I have the fund to do the 2.2L from top to bottom. At this point, I am almost convinced that I can achieve 220hp without turbo.

nokia8860
09-19-2003, 06:41 PM
Originally posted by CKlasse
At this point, I am almost convinced that I can achieve 220hp without turbo.

ALL MOTOR BABY!!!!









sorry that was like the only thing I could add on this thread :(

speedybenz
09-19-2003, 07:14 PM
CKlasse,

I think you can get 220hp to the wheels without a turbo, but you will have to increase the rpm limit to say 7500 rpm. But with good rods and pistons that would not be a problem.

Tapered cylinder bores are a bad thing. They should be round and straight. The pistons are tapered because they grow at different rates due to the amount of material at the top and bottom ofthe piston. But bores have to be straight and round.

You should look at Mahle pistons, they are the new Cosworth piston.

Also your valve guide idea is one I would pass on. The valves have to have good solid support to function well.

Also the Honda rod bearing size is worth a look as all the good bearing manufactures are making bearings in this size range and you can then offset grind your crank to pick up stroke and displacement.

Jeff

Three Point 6
09-19-2003, 09:07 PM
Originally posted by speedybenz
Ok, so you have an AMG C36 engine. First you tear it down and measure the deck ht. and piston to valve clearance, cam timing, etc.

Once apart you measure the crankshaft bearing journals. If the rod journals are bigger than a std. honda then you grind them to the smaller size and gain some stroke. The smaller bearing reduces the bearing speed and friction-more Hp.

2nd you get the wt. of all the stock piston, piston pin, rods and then go looking for something better and lighter. Same goes for the valves. Maybe you remove the stock valve guides and use new valve guides which allow valves with a smaller diameter stem to reduce wt.

3rd, you get the crank lightened and balanced. You also get it coated to shed oil better. less drag-more Hp.

4th, you get the head done. You may end up making the intake ports smaller, bgut with a better shape and since the valve stem is smaller you get more flow.

New cams with duration about the same as stock but with faster opening ramps. You have valve that weigh less so you can open them up faster to get more air in the motor.

Set your deck ht to .030" to take advantage of your new rods and batter pistons. Piston have total seal upper rings for near zero leakdown.

Custom header.

Slap it all together, set the cam timing to 105 LC on the intake and 110 Lc on the exhaust.

Now you have a 400hp motor.

Jeff

All sounds good, but I forgot that I would like this thing to be a street driver & at 12:1 compress ratio I would be worried about detonation. Considerations for cylinder swirl/design & piston top shape, engine cooling in relation to removal of cyl head heat, and high temp coatings on pistons, chambers would help combat all this and also - ECU/Dyno tune to tie it all together. Sounds great Jeff, how much do you think?? Renntech pricing in the end still even if I did it with local shops & DYI attitude? Since MB's are such an un-popular engine mod, it would be a shot in the dark edge cutter! I cant imagine how it would sound under throttle!!! Call me ludicriss but it might be more cost effective to slap a Z06 Vette motor or Buick G/N turbo driveline in there with stand alone ECU mgmt & cheaper/moddable overdrive transmission choices.

As a GM guy that has built a few V-8's I understand all your theory but I am not keen yet to the Honda rod bearing diameter. I am assuming that Hondas bearing size is 'very ideal' at this point through drag-ricer testing and makes a great proven start for strength/friction/technology.
The C36 crank is from the S350 Diesel & it is forged and already cut down a bit on the main Journels I believe??
C280 motors could go through the same rebuild assuming the same dual stage intake manifolding could be had & S350 cranks??
This could be fun w/ 1.1hp per cubic inch! ($$$money, money, money!)

Who did all the motors for MB when C36 was in the DTM, AMG or in house co-operation with AMG. I guess I mean, where can I get the specs for the actual race engine? Call AMG & speak a little German huh?

CKlasse
09-19-2003, 11:05 PM
sigh... I wish I could learn and work with you all in person. :(

BTW, when I mentioned tappered cylinder, I meant to ask what cause them. Ultra high tensioned piston rings? obviously, I will need to machine my block due to this issue.

speedybenz
10-01-2003, 09:39 PM
Junaidi,

I measured up my old C280 MAS and my C43 MAS. The C280 is 72mm in largest diameter but is tapered starting at 68.5mm.

The C43 MAS is straight through at 77mm. So a substanatial increase in flow area. Also I think the C43 MAS can be honed out to at least 80mm without undue difficulty.

CKlasse,

The taper is most likely caused by poor lubrication at the top of the bore and if your bores are cast iron it makes the problem worse. But yes the problem is the oil rings and 1st and 2nd ring scrape all the oil away from the top of the bore and so it recieves more wear as the piston comes up to a stop and then moves down the bore.

J Irwan
10-02-2003, 06:17 AM
Originally posted by speedybenz
Junaidi,

I measured up my old C280 MAS and my C43 MAS. The C280 is 72mm in largest diameter but is tapered starting at 68.5mm.

The C43 MAS is straight through at 77mm. So a substanatial increase in flow area. Also I think the C43 MAS can be honed out to at least 80mm without undue difficulty.

CKlasse,

The taper is most likely caused by poor lubrication at the top of the bore and if your bores are cast iron it makes the problem worse. But yes the problem is the oil rings and 1st and 2nd ring scrape all the oil away from the top of the bore and so it recieves more wear as the piston comes up to a stop and then moves down the bore.

Jeff,
what about the connector from C280 vs C43, are they plug n play (interchangeable..?)


Regardz,

speedybenz
10-02-2003, 11:08 AM
Yes the C43 and C280 connector are the same. Both 5-pin.

I put the C43 MAS on my C280 and it helped out quite a bit. I had to move the location closer to the engine but it was just a matter of putting it on the other side of the flex rubber tubing instead of connecting to the airbox.

This weekend I am going to measure the negative pressure in the intake system using a Manometer. That way I will be able to tell what items give the largest obstruction to flow.

Also if you have not removed your MAS screens, do so as these cause a large flow reduction. Removing them has no other adverse affects.

Jeff

J Irwan
10-02-2003, 02:40 PM
Jeff,

any pic of your MAS (c43 mass)

here is mine..(my old ones)

http://groups.msn.com/_Secure/0RwD*AmgUoL2fyi40JhwHab*FRtaLHwKoxiDM2Hp87PSk9jRPd ruueVJyhRnDe8ncCXENY2BYA9iBmYqcC3DJOB46h2YzJF5Sqxp spoXCVE8/DSC02269.JPG


the ID is 71mm straight through


Regardz,

Denlasoul
10-02-2003, 09:21 PM
Speedy:

In the picture JIrwin just posted, is that the wire mesh you are talking about removing?

DLS

speedybenz
10-03-2003, 06:45 AM
DLS,

Yes both the wire screen and the plastic screen. They just are not needed. The MAS fails due to other causes faster than it does due to wear particles, which should be caught by the air filters anyhow.

Jeff

J Irwan
10-03-2003, 07:01 AM
Originally posted by speedybenz
DLS,

Yes both the wire screen and the plastic screen. They just are not needed. The MAS fails due to other causes faster than it does due to wear particles, which should be caught by the air filters anyhow.

Jeff


Jeff any pic of your C43 MAS, I just want to make sure they fit.
Also you mentioned you used a C43 MAS on your C280 , do you remember how much you paid for a brand new C43 MAS..??


Regardz,

speedybenz
10-03-2003, 12:30 PM
J,

I will shoot you a pic tonight. I am paying $212? from Autohauz in AZ for a new one, but the one on my C280 I bought used from Pat at German Potamac Auto for $100.

I will make sure to get a pic of the mounting area for the sensor as that will be critical.

Jeff

speedybenz
10-05-2003, 07:56 PM
Pics of my MAS off my C43. The last one is where I machined the MAS body from 77mm up to 80mm.

http://speedybenz.home.comcast.net/715.jpg

http://speedybenz.home.comcast.net/716.jpg

http://speedybenz.home.comcast.net/717.jpg

http://speedybenz.home.comcast.net/718.jpg

Fantasmweb
10-08-2003, 10:34 PM
i have some book talk about the dtm c-class in early 90'. those engine is totaly different with c36. the engine is 2.5 L6 in dtm and can product 400 hp. due to the high Compression ratio so they need to change after every race.

speedybenz
10-09-2003, 02:37 PM
I put the sensor in the MAS body I bored out to 80mm and the car seems to be pretty damn fast. Easy to spin the rear tires at take off and if you punch it at 15mph the ESP light comes on.

I need to drive it some more to know for certain that its faster or not. It does feel sharper with the new MAS sensor.

Jeff

Denlasoul
10-09-2003, 04:59 PM
Speedy:

Where could I go to have my MAS housing bored out too? Would you consider doing it?

J Irwan
10-09-2003, 05:09 PM
Originally posted by speedybenz
I put the sensor in the MAS body I bored out to 80mm and the car seems to be pretty damn fast. Easy to spin the rear tires at take off and if you punch it at 15mph the ESP light comes on.

I need to drive it some more to know for certain that its faster or not. It does feel sharper with the new MAS sensor.

Jeff

nice...

So are you using new MAS with this 80mm enlarged MAS housing..??

Also If you don't mind could you email me the Part Number for the C43 MAS....??


Regardz,

speedybenz
10-09-2003, 07:54 PM
I took another drive after work and I am positive the car is faster. Some of this is due to the MAS sensor being new and some to the larger MAS body.

From a stand still, no brake, just hitting full throttle it spun the rear tires pretty hard. It did not do this before. My rear tires are 255/40/17 Kumho MX, a soft performance tire with a wide footprint.

Yes I will bore out the MAS body for a couple of you it is very fast and if you went to a machine shop I cannot see them charging more than $20 to have this done. So it might be cheaper and faster to have it done locally. But if you want, DLS and J Irwin can send there MAS bodies out and I will do the deed.

The part number for the C43 MAS is 0280-217-810-000.

Just send enough to cover shipping charges back.

Jeff

Denlasoul
10-09-2003, 08:17 PM
What tool do you need to remove the MAS from the housing? I know it is a funky star, but dont know the real name. Also, waht size tool would I need?

Thanks!

DLS

PS: Is 80mm the largest safe diameter to use in the housing? Can you go larger? Just curious.

CKlasse
10-09-2003, 08:25 PM
Go to your local home improvement or auto part store. Ask for Torx screw with mid needle. They will either look at you funny, or exactly know what you are talking about :) :)

speedybenz
10-09-2003, 10:10 PM
CKlasse if you want me to bore out your MAS let me know.

DLS, I think you could go to 80.5-81mm, but that would be the absolute max and then I am not sure about the how the part will hold up to vibration and other wear which could cause cracking on the edges.

Torx drivers are 6 pointed stars and the newest MAS sensor is held in-place with a 5 pointed driver with a hole drilled in the center. I had to lock on to that screw using a ViseGrip to get the screw out. It spins out firmly but easily.

J Irwin, if you have a spare stock MAS body send it out and I will open it up as far as possible. From your photo it looks likes there is lots of material to remove.

Jeff

CKlasse
10-10-2003, 12:21 AM
Just an idea..why not fabricate a bigger MAS tube? Simply drill a hole on the side to attach the plastic mount onto it? :)

speedybenz
10-10-2003, 08:31 AM
It would be simple enough to make a larger tube and weld a fitting for the sensor. The problem lies with upsizing the tubing leading to and away from the MAS.

In the case of the C43 the MAS is attached to a 90 degree elbow that then attaches to the throttle body. So if you go too big then you would need to enlarge both the elbow and the throttle body.

But if the gains are there then it would be worhtwhile to figure out a way to enlarge the tubing the throttle body to allow for the encreased air flow.

But before you enlarge anything remove the sreeens in your MAS. That is a big flow restrictor.

Jeff

J Irwan
10-10-2003, 09:06 AM
Originally posted by Denlasoul
What tool do you need to remove the MAS from the housing? I know it is a funky star, but dont know the real name. Also, waht size tool would I need?

Thanks!

DLS

PS: Is 80mm the largest safe diameter to use in the housing? Can you go larger? Just curious.


If it is star you will need to find a "security star" head screw driver

If it is a torx you will need to find a "security torx" head screw driver


Regardz,

misterblack
09-26-2004, 08:12 PM
speedybenz...
can you find out if the air fuel ratio is proper with the bigger MAS?

from what I understand...the stock ECU is programed for a specific MAS size. This could result in taking in more air, but not adding more fuel causing the motor to run lean. I could be wrong though.....

if the air fuel ratio remains at a proper running level.....I will change the MAS on my C36 to a larger asap.

thanks!

CKlasse
09-27-2004, 05:28 AM
Once the engine goes into the OPEN loop, the MAS reading doesn't matter anyway. The AFR is constantly monitored by the O2S.

SLAMMED_C
09-27-2004, 07:26 PM
Once the engine goes into the OPEN loop, the MAS reading doesn't matter anyway. The AFR is constantly monitored by the O2S.
Is the engine not is open loop at start up and when cold??.. and then goes into closed loop when warm?? and yes the MAS reading does matter.. it is constantly being checked and referenced to, as well as the o2 sensors and various other sensors. the MAS constantly monitors the incoming air into the engine.


from what I understand...the stock ECU is programed for a specific MAS size. This could result in taking in more air, but not adding more fuel causing the motor to run lean. I could be wrong though.....
The stock ecu isnt programed for a specific MAS.. I have know people to use the actual sensor form other benz models with the same connector of course and putting them into their stock MAS housing. and the fuel computer can adapt to more incoming air into the engine, the injectors can adjust the on and off time of the injector by 3 miliseconds either way.


It would be simple enough to make a larger tube and weld a fitting for the sensor. The problem lies with upsizing the tubing leading to and away from the MAS.
That would be the ideal thing to do.. replace all intake tube from the air filter to the intake tube to and from the MAS and to the throttle body.. there is no point to making the MAS tube itself larger if the intake tube is still the same size.. you wont be flowing any more air.. you need to make all intake tubing larger so that you get more air into the engine from the begining (air filter) to the end (throttle body)

MrSpace
09-27-2004, 08:15 PM
do if you get everything bigger, you need a bigger MAS

because if you take your same sensor into a bigger pipe, you MAS won'T know more air is getting in for the same "pressure" it reads.,

Etienne

CKlasse
09-28-2004, 05:17 AM
Originally posted by SLAMMED_C
Is the engine not is open loop at start up and when cold??.. and then goes into closed loop when warm?? and yes the MAS reading does matter.. it is constantly being checked and referenced to, as well as the o2 sensors and various other sensors. the MAS constantly monitors the incoming air into the engine.

It goes into open loop on WOT. Once the Air Mass signal goes beyond certain frequency, it's all open loop. ECU then stop reading most of the sensors. It applies a calculated amount of fuel, based on a stored fuel map in the ECU from the factory. MB ECU actually learns corrections stored while it was previously operating in the closed-loop, "adaptive strategies."

Keep in mind, this happens at higher RPM. At this point, the larger bore mass can make difference. :)

At close loop, ECU reads both MAS and O2S.

In SCCA, some guys "peg" their MAS reading to constant value to stay in the open loop.

Rocky
09-28-2004, 05:27 AM
Originally posted by Denlasoul
What tool do you need to remove the MAS from the housing? I know it is a funky star, but dont know the real name. Also, waht size tool would I need?

Thanks!

DLS

PS: Is 80mm the largest safe diameter to use in the housing? Can you go larger? Just curious.

took me 3 weeks to find it and one day i happened upon one. The thing was I was looking for a full screwdriver with handle and the sec torx head.

here's a hint..look for a security torx 'BIT' that attaches to a drill bit or soemthing .

speedybenz
09-28-2004, 10:57 AM
PS: Is 80mm the largest safe diameter to use in the housing? Can you go larger? Just curious.

You can go 84mm on the MAS. It is pretty thin but mine is holding up well.

jeff

Ashkan's C280
10-03-2004, 10:51 AM
someone did 88 I think it was in the other thread with this topic