190 e on carbs

[dolf]

hi, i hope somone can help me? i'm trying to put twin webber carbs on my 190e 2.3 16v cosworth and would like to know if anyone else has ever done this? or if there is a inlet manifold avaliable for the 8 port head, if not any advice or ideas would be great as i have not found much info on this over hear in england.
thanks dolf

[Don350SDL]

All I can offer is that the 201 was never sold with anything but fuel injection here in the 'states. I'm not even sure if a carbureted version was offered for the M102.

Don

[dolf]

Thanks for your help, but the injection system that comes on the 201 is very restrictive and i,ve heard of peaple in the states putting a differant injection system on that's less restrictive. what i'm looking for is an inlet manifold to fit twin webber 45's or throttle bodies on to the 2.3 16v engine which would give the best performance. i'm just haveing a little trouble getting one made or finding one for sale, but i'm sure someone somewhere will have made one for when these cars where used as race cars. i've found one for the normal 8v head but this doesn't fit the 16v head. if anyone knows anything please help becourse i really miss driveing my cosworth

[JimVillers]

Dolf ..... I install a SDS digital injection on my 16-valve. Expensive but it gives me everything that I wanted.

Converting the engine to Weber 45DCOE carb should be relatively easy. The 16-valve manifold in aluminum and you should be able to find a Weber manifold that could be welded onto it.

I have DCOE carbs on my 190SL and they are interesting to tune. You NEED a wide band air-fuel gage to even come close.

Good luck and keep us posted if you decide to tackle this project.

[Robby Ackerman]

Yes, Weber DCOEs.

See the attached photo.

[dolf]

Is that the standard manifold cut down, with another one joined on to fit the carbs? if so do you know how this was done? i've been told you can only weld ali to ali and not to steel, so would i need another cast ali manifold for the carb side?
thanks for the picture, i think that will really help.
thanks dolf

[JimVillers]

The manifold should be easy enough for a race shop to fabricate. Easier than trying to find/buy and adapt another manifold. Try talking to a salesman at Pierce Manifolds if you are serious.

[Robby Ackerman]

Dolf

I can't answer your question about the manifold. The Owner's name of the 2.3-16 190SL is/was Ken Cates, and four years ago he lived in the Rancho Santa Fe area (San Diego, California). I don't know if he is still in there. He had the work done by a customizer in the area. I don't remember his name, but he is well known for his work.

[dolf]

Thanks for all your help, the picture has given me a better idea of how to do it. i'm going to find an engineering company next week who can weld the manifolds, then its pritty easy from there on, apart from setting them up. i'll keep you posted on how i get on, but this is no show car it's just my smoker to have fun in and keep the miles off my 2.4 stroker mitsubishi evolution 3 that has over 400bhp and 500ft/lb that i'm useing to go to work in but its just not practical in traffic.
beast

[JimVillers]

Dolf .... For tuning the DCOEs, buy the Weber Tuning Manual from your Weber parts supplier (it has a Weber part number, not a book ISBN). Then get a wide-band air-fuel gauge to measure the fuel delivery. After that, tuning is simple, fun and very effective.

[MTI]

Manifold for the twincam M102 (http://cgi.ebay.com/MERCEDES-190-2-3-16V-INLET-MANIFOLD-WEBER-DELLORTO_W0QQitemZ220082064411QQihZ012QQcategoryZ9 903QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)

[dolf]

thanks for that it is going to save me alot of trouble and the daft thing is i've serched ebay countless time and never come across this :) :cool: :D

[dolf]

Hello, i have now got the manifold for the carbs and i'm really impressed with the quality of it. I have a set of twin 40's but i want to know if hese will be ok or will i need something abit bigger? any help would be great thanks in advance.

[JimVillers]

Dolf .... 40DCOE should be plenty of carburetor for your engine. The key is the size of choke (you probably ill need a 32 or 34mm) and then sorting out the jetting. As I said above, buy the Weber Tuning Manual from your Weber parts supplier (it has a Weber part number, not a book ISBN). Then get a wide-band air-fuel gauge to measure the fuel delivery. After that, tuning is simple, fun and very effective.

[dolf]

Thanks jim i'll build them up this weekend then, now i know this. I'll keep you up dated on future progress.

[matsalleh76]

Adopting Webers to a 2.3-16 is going to be a big project.

They are wonderful carburettors, fully tunable and can, if set up right, give you a power boost but it is a long and potentially expensive road to the optimum set up. I have been down the route often with pretty good success. Here are some suggestions/hints (I do not know your familiarity with Webers and some of this may be a bit pedantic......no offense intended):

a) For a 2300cc engine pair of Weber 45's with 36 or 38mm venturies is about ideal. Anything smaller will limit output but be much easier to tune. Your choice: a slow 16V with 40's & 32mm venturies or something faster with 45's & 36mm venturies requiring more tuning finesse.

b) Webers are tuned by changing fuel and air metering jets, tubes and bypasses. That can get very expensive: there are idle jets, air and main jets, acceleration jets, emulsion tubes, acceleration bypass jets, auxiliary venturies, and some other stuff I can not think of now. To tune the various stages of a pair of carbs you need access to four of everything except the accel. bypass. I was very lucky and inherited a complete range (hundreds) of DCOE jets, emulsion tubes, venturies, etc. -everything - all organized in wooden compartmentalized boxes. The stuff is probably worth $5000. Check the prices of jets and emulsion tubes to get an idea of the potential cost.

c) A good start would be researching (or better still finding) the twin Weber 45 set-up used on the old four cylinder BMW 2002 coupe. That would give you a base line to start playing with jetting and emulsion tubes. The 2.3-16 will probably not run too well with the BMW set up but it may be closer than starting blind or copying the set-up from a hot-rodded MG or Alfa and give you an idea of where you have to go to get it right. A second benefit of finding a BMW set-up: you can use the throttle linkage after altering it to compensate for the different spacing between the carbs on the 2.3.

d)Get a wide-band O2 meter set like the Innovate LM-1. It will cost +/-$200 but is worth it as it will tell you what the carbs are doing to the engine at each stage:from idle, through idle-to-main progression, during acceleration, at cruise, and at WOT. A poor-boy plug read will tell you a bit but is not as accurate and a real pain in the *** compared to a good wide-band O2 meter.

e) Initially getting the engine to idle and pull at WOT is relatively easy: a few changes of idle jets and main/air correction jets will get you there.

f) The hard tuning is getting it to cruise and progress smoothly through the idle circuit to main circuit transition. This occurs at about 2500rpm at cruising throttle and can be a real problem to get right. It would not be so bad but every time you go through the gears you pass through this transition and the engine goes all flat: either too rich or too lean as one circuit begins to cut out and the other begins to cut in. This is where it helps to have hand fulls for different idle and main and air jets and a few different auxiliary venturies to try: they all have an effect on the transition. The acceleration jet does too: it begins to weep a bit of gas at transition.

g) Keep a note book and record (on its own page) EVERY change you make and the results. Use EXCELL and print a form with a column each for: Venturi size; Aux vent. size; main, idle, accel., air jet sizes; emulsion tube and accel. bypass number. The last 2000cc Alfa I did generated over 30 pages of changes/results: some dead ends; others led on to improvements. Do not ask how many test runs but it took over three months to get it spot on.

h) Synchronizing a pair of Webers is easy if you have access to a synchronizer. Buy a cheapo from Summit racing.

i) Your gas mileage is going to be lousy.

j) Get on Amazon or eBay and buy every Weber tuning book you can find.


One major suggestion:

As mentioned in an earlier post to this thread, getting a car to run well on Webers is very satisfying but takes time, proper instrumentation and access to jets, so perhaps it would be worthwhile looking into EFI using throttle bodies that bolt to the Weber manifold. They are available from several manufacturers including Jevany in the UK.

Webers are old technology. Using that manifold with a set of Weber flanged ITB's & an after market EFI (such as MegaSquirt) will give you a fast, smooth running, more economical, easily tunable car, that starts every time.

You might want to contact Silvercosworth on the 190Rev Forum and look into the EFI conversion kits he sell for the 16V: ECU, sensors, looms, cranktrigger for EDIS, etc. Good stuff.

One final comment: with EFI you will never ever have to crawl around on the side of the road with your nose in the grass looking for the Weber jet you dropped.........


Cheers,
bobf.

[JimVillers]

Bobf ...... Good info and advice. Tuning Webers is a drip .... drip .... at $40 a drip for jets for the next test. EFI is a "one time" $2K and a fair amount of work to fabricate and install everything.

I had more fun tuning with my EFI system than my Webers.

[dolf]

Thanks for your advice. I would love to put throttle boddies on this car but i just can not afford it as i already have a money pit (also known as a mitsubishi lancer evolution), so thats why i'm sticking to carbs (for now). I've just rebuilt the carbs and replaceing the chokes to 36mm and i'm lucky becourse there are a couple of tuners near by who are legends on webbers, so it will save me the time and expence of jetting the webbers myself, although i will probably stick a wideband on there to keep an eye on things and just incase i fancy haveing a dabble at tuneing myself.

[Robby Ackerman]

If you're going the route of carbs, the Weber DCOEs are the best choice.

[JimVillers]

If you have a good Weber tuner, you will be ahead with carbs. Building a fuel rail was a much more difficult task for me than fitting a throttle body (I used a Ford Mustang 5.0 throttle body).

[dolf]

Sounds nice, what sort of power and performance are you getting from a super charger and have you got any pictures? I also have a problem with the ASD and was thinking of swoping it to an LSD, has anybody done this before or know if it's a strate forward swap?

[fredtga]

ok, i'm in the same boat with my 16V: i'm gonna try the carb setup for now just because i have two DCOE45 laying around;
i just got in touch with the guy from Greece (the one from ebay) who's selling the intake manifold so hopefully i will have it soon;
beside that guy, the only place where i found a complete throttle body kit setup (for EFI) which also contains the manifold is AK Sports from Belgium (www.chadil.be); yesterday i got the answer from them, super nice setup, but it's 2000euro;

ok here are the questions that i have for carburettor conversion:
1. what about the ignition modification? can we go with a distributorless setup? something maybe from MSD or so...
2. what type of fuel pump/fuel pressure regulator?

[matsalleh76]

I am not too hot on the idea of putting carbs on a 190 because there are better alternates but, if it is going to be done anyway here are some suggestions and sources of info and material and some related comments:

Jim: making a fuel rail is a pain. I bought one from silvercosworth. It was a straight bolt on for my 16V. No hassles. Anyone contemplating EFI for a 190 should contact him. He is a good guy and his products are top quality and well engineered.

Robby: Agree the DCOE is the only way to go. Mikuni & Delloto are fine carbs but its much harder to locate parts and jets for them. By the way some "new old stock" Weber DCOM carbs appear on eBay from time to time. They are cheap and look like DCOE's but are entirely different, use different jets, parts, etc and are worthless as replacements for DCOEs. Avoid them.

Dolf: The 201 ASD diff is wider drive-flange to drive-flange than the 201 LSD. Therefore the half shafts are shorter on the ASD, so if you are lucky enough to locate a good 201 LSD make sure that you get it complete with the half shafts. The prop shaft is the same for the ASD and LSD.

Fred: Here are some other sources of Weber pattern throttle bodies. Perhaps they are cheaper and will entice you to go for EFI instead of carbs:

http://www.twminduction.com/Home/Home-FR.html
http://www.throttlebodies.com.au/contact.htm
http://www.redlineweber.com/html
http://www.jenvey.co.uk/

Your questions:
1)There is a distributorless stand-alone programmable ignition retrofit set up utilizing an EDIS module and coil pack available here:

http://www.autosportlabs.net/index.php?title=MegaJolt_Lite_Jr._Users_Welcome

2) The Merc fuel injection pump puts out about 3bar (+/-45psi). Weber carbs require 3 to 4 psi so the Merc pump will have to be tossed and replaced with a more suitable self regulating (and cheaper) pump for carbs. Bendix, Facit, Autolite, etc make them. Alternately you could fit a fuel regulator to the original Merc system and knock the pressure down but that is another component to source and worry about. I would just replace the Merc pump.

Cost: say $200 for the ignition system, $200 for the manifold, $75 for a fuel pump, $50 for throttle linkage and misc hardware, $50 for a good air filter system,
$200 for a W-B O2 metering set.

Final comment (I won't give up): For a few more $$$ you could get a megasquirt ECU, a silver cosworth fuel rail, crank trigger wheel, new injectors, sensors etc and go EFI utilizing the original Merc intake manifold, throttle body, and air filter system. Sell the manifold & those 45's and go EFI.

Cheers,
bobf.

[fredtga]

great information, thanks alot

well, ITB + EFI is the final goal, but until i manage to get everything ready for that i just want to experiment with carburettors just because i have most of the stuff available plus i have experience with them... i had such a setup on one of my cars back in europe;

i got in touch with most of the companies that offer tbody setup, but the rare thing to find is the actual intake manifold;
guys from jenvey redirected me to AK sport from belgium and as i wrote in a post earlier, they were the only ones who have an actual kit ready for the 16V engine; it comes with everything preassembled, but no standalone management; it costs 1995 euro and here is a pic attached of it;

the only alternative is the guy from greece who sells the manifold on ebay; i got mine from him and depending of how you negotiate, he's willing to ship one to US for $350-$400;

after this, there are plenty of tbody/carb combinations with DCOE/DHLA pattern;

in my case i'm gonna start with the carb setup:
- 2xWeber DCOE45
- distributorless ignition: EDIS4, 36-1 trigger wheel, the controller from autosportlabs
- i'm gonna keep the stock benz fuel pump, but reroute the fuel thru a Holley fuel pressure regulator to lower the pressure for carbs

that's about it; i'll keep this post updated as i go on

thanks again for the great info

[fredtga]

received the intake manifold from Greece and it's a piece of art... great quality and finish, bolted perfectly onto the head, enough clearance between the intake and oil filter housing;

lots of bolts&pieces still to gather, but the project has started

[dolf]

ok i've partly taken your addvice and found myself a set of 45's with 38mm chokes and its comeing along nicely. but could anyone tell me if it would be possible to use the standard fuel pump and lines with the fuel return pipe? so basicly having a constant flow of fuel past the carbs in affect allowing them to take fuel when ever needed, any advice would be great. i thought it might flood the carbs with to much pressure but with a constant flow back to the tank there wont be much pressure.
thanks in advance

[matsalleh76]

Dolf,

The best way is often the simplest way.

Trying to cook up something like you describe is not worth spending any more thought on. I have no idea at all on how it could possibly work or why it would be desirable. Keep your engineering simple.

Webers operate best on a 3 to 4psi fuel feed. You have two practical and sensible choices:

1) remove the Merc fuel pump/accumulator/filter package, sell it or seal it in a plastic bag and put it away for some possible future use. Buy a Bendix, Autolite, Facit, etc low pressure pump rated at say 4 to 5 psi and install it with a generic plastic fuel filter in the cavity created by removing the Merc package. Plumb it to the existing fuel lines from the tank and to the engine, connect the Merc pump wire to the new pump and you are done. You will lose about 1psi from the pump to the carbs so a 5psi pump is ideal.

2) retain the Merc pump/accumulator/filter package and install a low pressure adjustable regulator and fuel pressure gauge (Autolite makes a good one) in the engine bay just before the carbs to drop the standard Merc fuel system pressure from ~50psi to 3-4psi.

In either option the fuel return line would be plugged in the engine bay as it no longer serves any purpose.

Frankly, I strongly recommend the first option. It is simple and a more elegant engineering solution because it gives you a matched fuel pump - fuel requirement system with no extraneous components (the adjustable fuel pressure regulator) to correct the pump pressure/carb pressure mis-match that retaining the Merc package presents.

Furthermore, in the second option, I do not like the idea of the Merc accumulator maintaining ~50psi fuel pressure (thats it's purpose) on a carb system when the engine is shut down.

Having pressure on the Weber float valve when the engine is not running is senseless and although reduced to 3-4psi, is potentially dangerous because the Weber float valve may weep and allow the fuel level in the float chamber to rise.

In the best case this will cause hard starting due to flooding. In the worst case the carbs will overflow and drip raw fuel into the intake manifold offering the fun possibility of hydraulic lock (and a bent rod) when the piston tries to compress incompressible liquid. There is also an inherent fire danger in this.

You are approaching this sensibly (except for the fuel return idea) keep at it !!

bobf.

[dolf]

useing the return method i mentioned is very simple the merc pumps are capable of suppling the correct volume of fuel the carbs require and i happen to already have a fuel pressure reg to lower the pressure if nessercery. so from what your saying the merc setup holds 50psi in the fuel system at all times including when the engine is off, so if i put a low pressure fuel pump in like you suggested useing the wireing from the merc setup, would the pump be on all the time even when the engine is off? also does the old merc injection system have a fuel pressure reg to maintain the pressure? you mentioned the accumulator how does this work?

[JimVillers]

Do not try to use the Mercedes fuel pump. It is turned on by the engine management system and will not run if the engine is not turning. Fuel pressure regulators are not reliable, especially from high pressures. The easiest option would be to install an electric pump in the engine compartment, powered from the ignition circuit. I believe that it will pull fuel through the Mercedes pump so all you should need to do would be to disconnect the electrical connection (worth testing).

[fredtga]

here are some pics of the intake received from the guy from ebay (greece)
very high quality and finish, perfect fit; it's a great guy to deal with, price from ebay is not fixed plus the shipping is fast;

regarding the fuel pump my initial idea was to use the mercedes pump and then with a regulator to knock down the pressure, but i changed my mind and i will use a regular electrical fuel pump special for carbbed applications;
The Mercedes fuel assembly is easy to take off and you can just bypass it with a fuel line, maybe insert there (under the car) a screen type filter.
There are on ebay for around $40 Facet electrical fuel pumps (2-4psi) which are great (i used facet before on twin dellortos).
Don't forget to insert before the fuel pump a regular fuel filter and obvious you'll have to hook up the fuel pump using a relay.

Other stuff:
- you can use a switch to turn on/off the fuel pump (good as anti-theft system)
- you can insert a fuel pressure gauge using a regular fitting or using a fuel pressure regulator; check out holley website, they have all kind of parts and addons for carbbed setups
- you can use your fuel return line by inserting a "T" fitting after the fuel pump or use a fuel pressure regulator which has a fuel return connector (holley has one); both sollutions work, used them before and had no problems

[dolf]

ok had the car running today first time for nearly two years!
one problem though the manifold wasn't the best fit, some of the holes didn't quite line up. apart from that it was good to see it running, just need to sort out what i don't need on the loom left from the injection system

[dolf]

oh yeah i forgot to mention ithe noise was amazing, can't wait to get it out on the open road

[JimVillers]

dolf .... It looks like you are not using a soft mount for the carburators. You may need a support rod to support them from below. Without the mount and the support, they will vibrate and posibly break a mount.

On the other hand, great to hear that it is running. Now you can begin to figure out how to make it run very well.

[dolf]

the carbs are bolted on to the manifold with springs if thats what what you mean by soft mounts? if not i'll have to look how to fix a mount somewhere off the engine.

[JimVillers]

Dolf ... That was what I was refeering to. The spring mounts should be enough for now.

[matsalleh76]

Dolf,

Please elaborate a bit on the comment that "some of the holes did not line up". Were they manifold to head stud holes or manifold to carb or (hopefully not) intake passages manifold to head.

Others interested in the same manifold need to know of potential snags.......

Thanks & congrads on the installation.

bobf

[dolf]

thanks bobf the problem was with the holes that line up with the head stud holes, everything else lined up fine and to cure the problem we just drilled the holes slightly bigger in the manifold.

[dolf]

can anyone tell me what kind of bhp and torque do you think i should expect? running on these carbs and what are the standard figures?

[JimVillers]

The 9.7:1 engine with fuel injection developes 167 HP and the 10.5:1 compression engine developes 185 hp. I don't remember the torque numbers, though it is something around 235 lbs-ft. I don't know what to expect with the carbs. Are you using Weber DCOEs? 40 or 45's?

Robby Ackerman

[dolf]

i'm useing 45 dcoe's with 38mm cokes.
how do you know which engine has which compression?
i've now had the car set up on the rolling road and it managed 175 bhp and 176 ft lb which is slightly up on what it had when i had it done with the faulty standard injection. he said it might still need a fine tune after i've put some road miles on and seen how it drives on road. but first impressions are good, the car runs well and is really smooth through the revs.

[pch2021]

WOW! that is ther craziest thing i have ever seen on a 16v. what was your inspiration for the conversion?

[dolf]

I've always liked the sound of twin webbers, i think the're quite a desinctive sound and with the injection being faulty it seemed the perfect solution

[JimVillers]

The CIS injection may be good for economy but I would expect that the Webers could be tuned for better performance. I am a DCOE fan and would love to have the opportunity to drive the car.

Have you spend some time tuning the carbs? I set my Webers up on my 190SL with a wide band air/fuel ration gauge with the help of the Weber Tuning Manual from Weber and my car has never run so well.

[dolf]

Well i haven't tuned it myself, i took it to a garage who has plenty of experiance with webbers. it was set up an a rolling road and mike the macanic said that it was running well on the rolling road, very smooth through the whole rev range. and he did it all in one day.
he now wants me to put some real road milage on the car to see if there are any flat spots that might need smoothing out with a little bit of fine tuning.

Jim if your ever in england around the manchester area i would be happy to let you have a go, as long a you can drive a manual gearbox as i know you americans love your autos.

[caira911]

Hello everybody,

I have been searching for a discussion like this. I own a 86 2.3 16v and have been dying to do this setup. I have the same problem with my cis system and looking to do a carb conversion. I myself is a fan of the side draft carbs and love the sound of it.

dolf:

what type of ignition system did you use? I am looking for a cheaper alternative to get my timing to advance under load. Any advice would help me alot. Thanks

[dolf]

what type of ignition system did you use? I am looking for a cheaper alternative to get my timing to advance under load. Any advice would help me alot. Thanks[/QUOTE]

im useing the stanard ignition system at the min and it seems to work just fine. i think you can advance and retard the ignition with a switch that is located near the battary, but if its an american car you wont have this, you'll have a box that retards the ignition to a preselected setting for the poorer quality fuel, i think this can be removed tho. hope this helps? have a search on here as this is where i found out about it

[caira911]

Let me get this right. You are using the oem ignition system? What happens at WOT? How hard does it pull? I took out the resistor that mercedes put in to retard the timing already. Helped a little bit.I'm just concern that if i do this conversion and use the existing ignition, I won't be able to utilize the full potential of the carbs. By the way how is your car running? Its been a few months since your last post. Anyway thanks for your info. I am talking to John from greece about the manifold, hopefully he can give me a deal. Oh, I also picked up an 87 2.3 16v today has a worn timing chain guides. Guy that own it took it apart and didn't realize it was going to be difficult to source parts for it, so gave up. Gonna use it as a donor for my 16v. and sell parts off of it. Thanks again.

[dolf]

it pulls just fine and i use the car everyday, it made 190bhp on the rolling road recently. i might get more from it if i used a differant ignition system, but it runs fine so i dont see the point in changing it. the ignition system on mine is ajustable but i dont think the us version is, but i could be wrong.

[caira911]

That's great. Your right about the adjustability the US version only has the resistor to advance the timing about 6 degrees w/c I have already removed. Thats really good to hear, in that case I can proceed with my conversion. Thanks dolf!