This should answer many questions for most of you. It surely opened-up my eyes quite a bit. and also made me realize why additional performance on this car is so elusive and over-priced. After discussing this with my MB race mechanic, we believe we have come up with some solutions for more HP. The first drawback is that the 3 valve configuration was specifically designed to lower exhaust emission "Three valve engines develop less torque and less HP than modern 4 valve engines because the limited flow". And this emissions standard has also been achieved by retarding the timing by 5-10 degrees via the ECU. That's why I get a AFM ratio of 14.4:1 when I dyno my car.

I'll let all of you read through this before I get back to the thread with a follow-up and some answers. http://www.whnet.com/4x4/new_V6.html

Also I have this nice bit of information regarding the ESP when you turn off the switch. "It disables the engine-torque-reduction capability and thus reduces the computers' intervention capabilities to about 20%". So, as I suspected, you cannot turn off the ESP completely without disabling the system via the computer. But, I never realized that it cuts the engine to achieve its results, before I got into this info from my mechanic.

http://www.whnet.com/4x4/esp.html

 

Thanks for the good read.
Can't we just change the springs and weights in the distributor and toss some jets at it?
Port the heads and install some larger valves.
Or at least the modern version of this?
I understand cars are factory tuned for economy and emissions, they have been for a long long time.

Usually you can take the trade off and loose some economy and pollute some more to make more power. Why is this so elusive on this car.
Faster spark and more fuel and air should still = more power.
So in theory if we put on a free flowing exhaust, bigger mass and intake parts to allow more air in, port the heads, change the timing, change the fuel injectors and pulse width.
Would we make more power that is worth doing? or would it be minimal?
I know parts for this motor are big$$$ or just not out there.


It may be cheaper to stuff a used 5.5 motor in it out of another MB car. That would be fun.

 

Is the crossfire engine the M112 talked about in the article?

 

Quote from article "Using one less exhaust valve also makes room for two spark plugs per cylinder,"

I had no idea that we have 12 plugs.

 

Yes 12 plugs.
Spark should not be an issue, I would like to advance the timing via the computer though.

 

Is there any chance the reason they retard the timing is because there are 2 spark plugs???

This feature of an extra plug probably helps build more torque, by getting such a quick burn rate from the 2 plugs it may not be necessary to advance the timing, also it is putting less work on the piston because of the two plugs firing at different times during stroke and the ability to burn so much more efficiently, you might be creating more problems by advancing your timing and not make anymore power.

 

I don't have any definitive answers to all these questions yet, but I have the best guys I could find, trying to figure it out. The owner of this company, Mike, has taken a keen interest in my racing exploits in the Crossfire (112 engine). http://www.mercedesengines.net/ Thankfully they are very local to me.

It's a hell of alot more interest and information than I ever got from Diamler/Chrysler.

 

wow, this sounds promising.

 

So what kind of ideas do they have? Maybe they can over bore some new cylinder sleeves and make up some larger piston kits, I know startec makes a stroker crank kit for the 3.2 XF which bumps the power to 340 hp normally aspirated, maybe they can do a similar kit and install those Shricks cams too?
These options sound like a better way to go instead of S/C's and T/C's which are both major head aches to fabricate. N/A is the way to go!!

 

I hope they do something to uncover those extra horses... anything for performance...

 

Primary things I can think of would be more improvements on in general. For racing applications, Like...

1. ECU/computer system improvements. When you turn off traction control the ESP is really off, not just partial. Put the control back in the driver's hands. (not for everyone as people do stupid things and get hurt/killed). Simple Fuel, timing remapping (similar to what Upsolute and RennTech do, but more aggressive).

2. #1 above, pulse larger injectors could be introduced along with an even more aggressive timing curve to allow much more exotic fuels to burn at manageable temperatures.

3. #1 + #2 and ECU reprogram and mild - always on roots style blower change out for more raw horses. (around 10 psi blower).

4. All of the above PLUS swap out the aluminum pistons and rods with forged pieces. (similar to the changes made for the SRT6 engine). In this case the blower could be more aggressive (14 psi or more).

Beyond that, I'm not sure.

 

#3 and #4. wow, that's a HUGE step from where we are now. and the srt-6 should be fine with its internals, isn't it already forged and hand built?

 

Meaning the same changes that are already done for the SRT6, but not at Mercedes prices...

 

sorta what i figured, sounded like another "just buy an srt-6 post" from an srt owner.

 

Anyone know how much the Startech 3.8L kit runs about? I'm not sure the 300 Hp is worth all the money they're asking...

http://www.startech.de/p13be.htm

 

i think its like $12,000 grand and the other one is 30 plus. its ridiculous, just a show car thing. they tried to sell the 6.0 liter one for 120,000 pounds i think, if memory serves me correct...

 

Regardless of price, they told me that they need your engine or car there to put in the 3.8 conversion kit, so unless they changed their minds about that it wont work. I remember the 30 Hp kit started at 3k than the next up is 12k. They will ship the 3k kit but I trust you wont give it the time of day for 30 Hp right?

 

As my MB engine guru always says "HP costs money, how fast do you want to go ?"

 

You mean how fast do you want to spend? Lol.

 

What a joke, they are asking stupid prices, how do they stay in business and make money???

Anyone know who makes the stroker cranks for the LS1 camaros? I wonder if I called around, I could get a domestic company to make us stroker cranks and new pistons!
I'm not familiar with the Domestic aftermarket, but I don’t see why Comp cams or Scatt Cranks couldn't do as good a job as Startech, Shricks or Brabus...