TTM Fuel Rail / Injectors ---> OE Tuned!
As of the last post from Bruce at TTM, "There is only one tuner with experience tuning this rail and injectors".. not any more....
We installed the new TTM fuel rail yesterday at OE Tuning in Van Nuys CA, and Jeremy went to work tuning. Process took a few hours to find the sweet spot, but when the dyno dust settled...
Not only did I make more power throughout (+25HP to +30HP), Jeremy was able to extend the powerband out to redline, (+56HP @ 6100). We compared a lot of OE Tuned E55 graphs, and they ALL fall off around 5600. Now, we are able to carry peak HP all the way to the limiter.
Bruce claims 25 HP with the rail, however what he forgot to mention is that the added HP carries forever, and realistically, the gains surpass what a chart shows. Drivability is better than stock. Smooth Idle, immediate power... But it PULLLLLLLLLLLLLLLs now...
Jeremy did an awesome job tuning this, and I know there will be more to come from OE Tuning once all you f^*%$ get the idea to do this.
Although it was over 100 degrees, Jeremy was able to wiggle 492 HP out of the car on 91 pump gas.
Big Thanks to both Bruce at TTM and Jeremy at OE Tuning for making this happen!!
Last edited by Bramage; Jul 3, 2011 at 09:34 AM.

From 5000 to 6400 power stays flat and only in the last 100rpm does it dip ( probably from reaching the revlimiter ).
Again, I'm not knocking the fueling system since I do see it's advantages.
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Other new people to the forum seem to go off what they know from other cars not MB's.
Every car has it's weak points.
Any good engine builder or tech will tell you every monster build has it's demons and #8 is ours lets hope this keeps it in the closet.
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Other new people to the forum seem to go off what they know from other cars not MB's.
Every car has it's weak points.
Any good engine builder or tech will tell you every monster build has it's demons and #8 is ours lets hope this keeps it in the closet.
, Bruce
and to Dane for putting his car out there.
The TTM fuel rail is a closed loop which equalizes the pressure across the injectors. The factory fuel rail has a pressure drop from the first to the last injector on each line. At some level of tuning the pressure drop in the factory fuel rail will become a performance bottleneck.
For what it's worth....
There is no difference in the way the fuel is delivered to the rail (from the back) from many other cars so saying it is because it builds pressure from the front is irrelevant if you ask me. Think about it for a second, having the rail looped just causes the fuel to come in the back like normal and then build pressure back once the fuel meets each other on the two front sides where it is looped instead of hitting the end of each rail and then working back. It is doing the same thing, you guys are thinking to much in to this.
We held at 11.0 AFR at top end. Tip in held the same pattern as all other final tunes I have done with Jeremy, and we left the other .5 on the table due to the temps (+100).
The car feels 500 LB lighter now... Effortless power
I DO see the point of the rail. Mt previous car beforethe E55 was an Infiniti G35 and when I went with an aftermaket fuel rail the pressure would hold much more steady and any fluctuations would be smoother. Once I went with a fuel return system, the fuel pressure was pretty much rock solid.
While a fuel return would mostly be useless on the E55, I can see the benefits of the rail. It's all theory though, so I would definitely love to see the proof urbamworm is looking for.
A fuel rail is shorter than a irrigation pipe so there's less of a pressure drop but engine builders still have to account for the pressure drop in their engine design. For the 55K engines Mercedes determined that the end-supplied, straight fuel rails were sufficient. However for the SLR engine Mercedes used a loop fuel rail rather than the straight rails from the 55K engine.
Ferrari uses loop fuel rails too, at least on some of their engines.
Don't just take my word for it. Read around a bit and you'll find lots of sources that confirm what I've summarized above.
I inspected the mixture graphs on the dyno, and we also logged short term and long term fuel trim levels through the zietronix.
Also pulled some comparative numbers between the zeitronix and the dyno. Once the injectors were scaled, and we had our stock maps happy at idle, we were running very rich up top 9.X.
Jeremy is very methodical, and does not make large changes. Through the next 4 pulls, we brought this up. The tune is very conservative if you ask me, but I am not a tuner. We flat line around 11.0 where we are making 185 - 192 HP. Tip in is very typical to all other pulls I have made on the Gintani / OE Dyno.
Urbam
The gains are from the fuel rail and injectors. There might be a little in the rail by preventing starvation, however the two together produce the claimed HP.
If you count HP and Torque gains at the very top end, I picked up +50 of each. Through the range, I picked up between 25-30 HP as the dyno shows.
The comparative dyno numbers are from my last tune, done in September. The only change between the two dyno graphs is the date, and the rail/injectors.
If you are looking for proof that this modification adds power, look no further than post #1.
Bruce will have to chime in the the how/why, but here is how I understand it:
Dual Spray Pattern directing fuel directly into intake runners adds a lot of fuel efficiency, which means you can get more power with the same amount of gas. Without atomization, the fuel does not burn efficiently, or produce power efficiently. Bruce?
PS- Jerry did a write up as well, and confirmed gains, so this is supported data.
The thing is, there really is a pressure drop when fluid runs through conduit whether it's a fuel rail or a water pipe. Loops also really do equalize pressure, whether it's an irrigation system on a farm, a multi-head shower system, or the fuel rail on a high powered engine.
A fuel rail is shorter than a irrigation pipe so there's less of a pressure drop but engine builders still have to account for the pressure drop in their engine design. For the 55K engines Mercedes determined that the end-supplied, straight fuel rails were sufficient. However for the SLR engine Mercedes used a loop fuel rail rather than the straight rails from the 55K engine.
Ferrari uses loop fuel rails too, at least on some of their engines.
Don't just take my word for it. Read around a bit and you'll find lots of sources that confirm what I've summarized above.
I agree. That is why I believe there are benefits from the looped fuel rail. People have thought alot about the fuel rail. A solution resulted. The solution is consistent with higher end engines and how fuel issues were addressed by other aftermarket vendors for other cars.
I also look at it another way. Show me proof that there are no benefits, bc there is proof (such as it being in other high end cars) that there are benefits.
have you done normal driving around town logging and WOT logging to see that this file for the new injectors rail is up to snuf
?

In terms of logging- Yes. I am logging all the time, and I am paying close attention with the new tune. It is spot on. As I mentioned, drivability is improved. Idle, cruising, responsivness all better. And when I get on it, it is a different car.






