M119 full throttle fuel enrichment questions - PeachParts Mercedes-Benz Forum

400Eric · #1 06-08-2008, 04:01 AM

As I understand it, the power drop between the 92 500E and 93 500E was due to benz turning down the full throttle fuel enrichment and that under full throttle, there are no air/fuel ratio adjustments being made by the computer because it is in an "open loop" condition so it relies on the pre-programed factory settings. If all this is true, then if we put a very high flow exhaust and a nicer/colder ram air intake are we going to lean our cars out too much? Did this same "turning down" happen to the 93 400E but the power loss was negated by the increase in compression that the 4.2 received? (And why didn't the 5.0 get that increase?) Is there anybody out there that does "chips" for us? Is there anything else that can be done?

(Please I want to keep my 2.24s.) We live in a day of 381 horsepower 14 second toyota pick-ups

friends and we need to prepare ourselves!

Thanks to all that respond. Eric

c280nz · #2 06-09-2008, 02:42 AM

you could probebly raise the fuel pressure to get more fuel flow out of your standard injectors up top

400Eric · #3 06-09-2008, 03:26 AM

Please forgive my ignorance, but what is the best way to do that and are there any potential downsides?

400Eric · #4 06-10-2008, 01:06 AM

JRF engineering. He seems like a great guy doing good deeds. Anybody with an M119 try one of his chips? What do you think?

EliotW · #5 06-10-2008, 01:43 PM

There are no performance gains from chipping the M119 motor. At best you'll move the power band around.

Unless you have a particular affection for your E420 it would be far more cost effective to purchase an E500 or similiarly more powerful model.

jhodg5ck · #6 06-10-2008, 11:43 PM

I'm not too sure if the 400E suffered the same fate as the 500's..

That aside, your best bet power wise would be to open up the exhaust from the down pipes back...high flow cats, x pipe, proper high flow muffler etc..

If you really want to make it move I'd look at an STS turbo...
http://www.500ecstasy.com/forums/showthread.php?t=1544&highlight=change+sensor

M119 would do well w/ a little forced induction;-)

Jonathan

Turbo E320 · #7 06-11-2008, 01:48 AM

If the car has a MAF, MAP, or Karmann sensor just wire a SAFC to it and enrich it yourself. I did to my E320, it only took an hour and it was the first time i wired anything. Now ive wired stand alones, other piggy backs, and stock ECUs into cars because its just that easy once you figure it out.

400Eric · #8 06-12-2008, 02:37 AM

(and with $4.50 gas that may already be happening as we speak---it's already happening to 400E/E420 values). In the meantime, I need to pump-up this 400E a little. looking at the long term plans, I'd like to turbo it but the 11 to 1 compression gets in the way. I'd really like to swap in a 5.0 M119 with it's slightly lower 10 to 1 comp. , turbo it and then run it on propane or natural gas. The higher octane of those fuels would allow decent boost to live with 10 to 1 comp. (Not so sure about 11:1). I'm searching for info about swapping in a S-class 5.0, But the threads I've seen just basically say "don't". I'd like to see more on the topic. Does anybody know where I can go?
Anybody else out there know if the '93 4.2 suffered the same fate as the '93 5.0? As I said before, I'm all for opening up the exhaust. But I want to be sure that this doesn't make what may be an already lean eng. too lean. The chip maker says the chip adds a little more fuel and timing. Sounds good to me, what do you folks think? His 1.1k resistor mod works great! And it's cool that he tells you how to do it yourself so you don't have to spend the $ to buy the "cool harness". With the $ I saved, I can now afford to buy his chip! I want to do this. Please somebody tell me it's OK. Tell me what I want to hear just like the politicians do.

Thanks again to all who respond/responded. Eric

400Eric · #9 06-12-2008, 02:55 AM

Quote:

Originally Posted by Turbo E320

If the car has a MAF, MAP, or Karmann sensor just wire a SAFC to it and enrich it yourself. I did to my E320, it only took an hour and it was the first time i wired anything. Now ive wired stand alones, other piggy backs, and stock ECUs into cars because its just that easy once you figure it out.

Again, please forgive my ignorance, but what is a SAFC? I do know that my car has a Hot Wire MAF.

400Eric · #10 06-16-2008, 07:59 PM

I want to know if the chip he sells removes the top speed limiter. If it doesn't, I'll be looking for one that does. I don't want a chip that leaves the limiter intact. Please Benz brothers, I need some help here. Also, did the '93 400E receive a first gear start? Mine has it and I don't know if it's because it's modified or not? It sure acts stock and natural the way it behaves but I thought the first gear start came later. Even the E class Bible is not clear on this (even though the author owns a 93 400E). My thinking is that if a previous owner did a first gear start, maybe he did a chip too?

One can always hope. The problem is that not all chips remove the top speed limiter so I don't know how to find out if "Benzer III" has been chipped already. Please, I really do need some help here. Thanks to all who respond. Eric

400Eric · #11 07-02-2008, 06:59 AM

Jim F's chip does ditch the top speed limiter, but I still need help with my other questions. Please! Anybody? Regards, Eric

jhodg5ck · #12 07-02-2008, 10:11 AM

The two @ my shop now start in 2nd.

I'd going to wager there is MORE then enough head room in the FI system to compensate for an open exhaust...

Jonathan

400Eric · #13 07-05-2008, 02:31 AM

Thanks Jonathan for your response. My issue is that the 93 and later 500E saw a horsepower loss in a stock configuration with stock breathing when Benz trimmed the fuel. That tells me we are not supplying enough fuel for the air that is already there, much less the air that we want to add with exhaust and headlight panel mods. Case in point: The 500E guys seem to find their lost power when they put 92 brains in their cars without any other changes. So my crazy thinking is: change the chip since it is the brain of the brain. I'm just trying to throw a little more air and fuel through the eng. and gain about 30 HP. and 30 ft. #s of TQ., maybe get a 14.7 sec. quarter mile in total street trim (for now). Getting enough air seems to easy. Now how do we get a little more fuel in? I went out of my way to get a non-ASR car so I wouldn't have any issues with that holding me back. (Saves a little weight too). The car weighs 3640#s which is the lightest # I've ever seen for a M119-124. I love this car and I don't want it getting spanked by a Toyota P/U! Regards, Eric

jhodg5ck · #14 07-05-2008, 11:00 AM

Yes, I'm aware of the early vs late ECU's and the early vs late HP figures...

Were I in your shoes I'd invest in an Innovate wide band a/f ratio meter and see what you have. Throwing parts at an equation that's still missing a critical piece info isn't the recommended method.

The last 500E we put a cat back system on woke up w/o any other mods, so I still believe their is more then enough room in the stock setup to compensate for a better exhaust system.

Jonathan

400Eric · #15 07-06-2008, 12:50 AM

You are right, throwing parts at the car is not the answer. That's why I'm asking those wiser than me before I jump in. The wide band a/f ratio meter is good advice. If we assume for a moment that the 93 and later 400E did suffer the same fate as the 93 and later 500E did, (which I strongly suspect it did) we can also assume (bad choice of words I know) that my 93 400E would make more power if I added more fuel at WOT. What is the BEST way to do that? Short of trying to find a 92 brain, Wouldn't finding a chip programed like a 92 help? I know there are a lot of bunk/bogus chips out there, But surely there is at least ONE brand that works right...right? What year was that 500E? What where the horsepower and torque gains? Thanks again for your help Jonathan. If you ever get tired of your 87 Hammer, let me Know. I have the Car and Driver article that featured that car. Do you want a copy? You probably already have it but I thought I would ask. Regards, Eric