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Not sure if I should be posting this here, or in the S65/amg forum...but here goes. If a mod thinks it would get more attention in another sub-forum please go ahead and move it.
Firstly, I'd like to apologize...I can get kind of wordy and ramble on, so this and future posts will probably be quite long. If you don't want to read it, then don't. Ok guys, I've had my 2004 S600 for about a year now and am looking to do some more upgrades. When I first bought the car it was in pretty good shape, but I STILL managed to find about $3,000 worth of maintenance to do (and I do ALL my own labor). Point of the story is, everything mechanically is 100% now and it's been smooth sailing for a while so I'm looking for some more power.
So far, I have Eurocharged ECU and TCU tunes and a single large water/meth injection nozzle. I am looking for ideas for where to go with it next. I am very familiar with turbocharged/supercharged cars but a lot of things on the S600 are just plain hard to find out information about so I thought I'd ask for ideas rather than just find out the hard way. I have purchased some spare parts to perform any permanent modifications on so I will be able to return it to stock later, but I'm looking for feedback on my ideas and other ideas to improve power output. I am not interested in buying $200 parts for $1,500 as seems to be the case with what aftermarket items are available for these cars, but I AM interested in knowing which of these items are worthwhile mods so that I can fabricate my own versions.
The modifications I have have planned are as follows:
1. Fabricate new catless downpipes with electric cutouts
2. Install a spray tube with ultra-fine misting nozzles inside the intake manifold to achieve much better distribution of my water/methanol spray (I currently have a single 12GPH nozzle immediately pre-throttle body which causes the car to bog/misfire if I come off the throttle too quickly).
3. While I'm at it, I will be installing spray tubes for nitrous oxide and the corresponding enrichment fuel for potential future use.
4. This is the big/ambitious one: I am going to add a second set of factory intercoolers in series, probably approximately in the location of the stock filter boxes, and run those two on the factory cooling loop/heat exchanger as a first stage of intercooling and run the existing two factory intercoolers on a separate chilled reservoir mounted in the spare tire (yes, IN the wheel so I will still have a spare if needed) utilizing an extra evaporator plumbed into the car's A/C system to make my own ice water. I have been doing this in my Buick for years now with unbelievable results. I hadn't been seriously thinking about doing it on the Benz because of the cost...but I recently scored a second set of intercoolers for $150 for the pair, so I'm all over it now.
For those not familiar with the math, if this second stage drops my intake temp from 100 degrees F in the manifold to 40 degrees F (85% intercooler efficiency with ice water in the tank...which is conservative since I can chill to below 0 F), that will be a 12% power increase from the density improvement alone, or 72 horsepower on 600 baseline horsepower. The reason for series intercoolers as opposed to just single-stage chilled is twofold. First, if I did it in a single stage, the final temps would be something like 75 degrees in the manifold...when you stack efficiency in series, you end up with a total efficiency approaching 100%. Since my cores will be at different temperatures, they are still separate calculations but the net effect is significantly cooler air from two stages than one.
Secondly, the first stage of intercooling is going to take the bulk of the BTUs out of the air because of the higher temperature differential. That air is going to be something like 320 degrees on an 80 degree day coming out of the turbo @ 20psi. If the first system is an ambient 80 degrees, that's a 240 degree temperature delta. After the first intercooler it may be 110 degrees, which is only 78 degrees from my chilled second stage. So approximately 75% of the BTUs removed from the air charge are going to go into the first stage intercooler, which means my recovery time to chill my water back down with the car's A/C is going to be 4x faster than it would be if it were just a single stage. Water misters on the heat exchanger and condenser will of course speed this considerably as well.
5. This will require deleting the airboxes and fabbing up a cone-type filter intake to make room. While I'm going to the trouble of making new intakes, I would like to also install some pre-turbo misting nozzles to stretch the compressor maps a little further.
Some of the questions I have are related to how the car manages boost. I assume it is all computer controlled through a boost control solenoid of some sort, and that this value is simply increased by most tuners (along with various AFR and timing and electronic throttle adjustments)? The question is, I have often in the past simply capped the wastegates and essentially let the stock turbos run wild. Which works incredibly well on 3000GTs, but can anyone comment on whether the S600s computer will play nice with such a setup, or if it will pull timing or go into any kind of limp mode due to overboost? I'm sure that might be a good question for Jerry @ Eurocharged, but I bug him way too often as it is so I thought I would ask here first.
Now, I'm well aware that running the turbos over their redline is going to negatively impact their longevity...and that depending on how the flow map responds above and beyond what is normal, I could even make less power up top that way, but it's something I at least want to experiment with and would love to hear feedback from anyone that has run these turbos all out.
Another question I have is what injector size these actually have and how much the fuel pump will flow before needing an upgrade. Specifically, has anyone run E85 on the stock injectors? Jerry indicated that his tune hits about 76% injector duty cycle, which would basically put it at 99% on E85. Most tuners don't push that over 80%...I have had consistent results pushing it as high as low 90s on other platforms. I have heard they are 39lb injectors but have not been able to verify this. I can only get 91 octane here (hence the water/meth injection), so E85 would be a no-brainer if I could run it...but I don't want to buy 12 $100 injectors to be able to do so. Has anyone converted to a return-style fuel system and bumped up the pressure to get more out of the stock injectors? I haven't looked too hard, but I am assuming these cars are returnless. Obviously that would most likely require a pump upgrade or booster-pump inline to handle the extra pressure, but could be a much more economical solution than a new set of injectors since a pair of 340lph pumps would only cost me $120.
Anyway, does anybody have some ideas that I may be missing that would be easy enough to do while I'm at it? Thanks in advance!
Got the exhaust dropped tonight. Man those vbands on the downpipes are a pain! After looking everything over and measuring, I think I am just going to cut the cats out and replace them with e-cutouts rather than trying to remake the pipes from scratch. I mean they're plenty large...basically pretty close to 3" anyway. And I only really care about the first foot of piping anyway for power purposes since I plan to dump the cutouts basically right at the back of the engine bay.
I took the opportunity while I was under the car again to try and pinpoint a slight engine noise I'd been hearing for a while. Turns out it ALL of the idler and tensioner pulleys on the serpentine belt are rough, so I went ahead and ordered new ones plus a belt. Got a carrier bearing for the driveshaft as well, it seemed to have quite a bit of slop in the rubber. There goes $350, but those are just about the only maintenence items I hadn't done yet. Glad I caught it early and didn't pop the belt and have to tow it home.
Also removed and disassembled my remaining original coil (passenger side was just replaced) and ohm'd everything thinking I would find at least a few dead sticks that I could swap good ones out of my old passenger side coil, but everything checked out fine, so I guess that was a waste of time. I had 3 dead sticks on my driver's coil when it finally went into permanent limp mode and it hadn't had a noticeable misfire up until that point (all 3 were on different cylinders) so I figured the other coil might have the same scenario, but I guess it's ok for now.
Looks like I'm going to be waiting on parts for a while now, so it may be a while before I update again...probably will give the other cars some attention while I wait on everything.
Thanks for chiming in, I was wondering if I was just talking to myself...
I will try and get some pictures up as I actually make some progress, but I have to admit I don't often remember to stop and take pics when I'm working, so there might not be a whole lot of them.
Most W220 owner here does NOT care much about power mod, just because you can't do much on a S430 or S500 or pre-2003 S600. Common mod like ECU tune, exhaust and air filter. A few may replace the header. For S600 with twin turbo, we may do the ECU and TCU tune, CAT or muffler delete. Your mods is more than bolt on parts and need a lot of R&D, you can either find a good Mercedes tune shop( tune your car at dyno) or you do everything yourself . Keep post and may be with some pictures, you know people like to see pictures !!
Most W220 owner here does NOT care much about power mod, just because you can't do much on a S430 or S500 or pre-2003 S600. Common mod like ECU tune, exhaust and air filter. A few may replace the header. For S600 with twin turbo, we may do the ECU and TCU tune, CAT or muffler delete. Your mods is more than bolt on parts and need a lot of R&D, you can either find a good Mercedes tune shop( tune your car at dyno) or you do everything yourself . Keep post and may be with some pictures, you know people like to see pictures !!
Yeah, I usually prefer to do everything myself, including tuning, but couldn't find any definitions files or software that would let me do my own tuning. I'm all ears if there is something out there, but Jerry @ Eurocharged has been great about making any changes I want. I am used to platforms with large, relatively inexpensive aftermarket support...but with the kinds of crazy ideas I have I usually have to end up building most of my own parts anyway so that's nothing new.
Looking into trying to squeeze the X3 radiator in as a heat exhanger while I'm at it. At least a good road map has been laid out for that swap.
Looking into trying to squeeze the X3 radiator in as a heat exhanger while I'm at it. At least a good road map has been laid out for that swap.
That's what I did a few years ago, and I'd be chuffed if someone else did the same thing. A word of caution though. You have to cut the right hand side headlight bracket a lot, and fitting the outlet pipe is difficult - worth finding another solution. I always wanted to fit a Mercedes W124 radiator, and may do that on my next project. The easy alternative is just to fit an S65 cooler.
Don't mess with the wastegate - it works under PWM closed loop control. Leave fuel, ignition and boost control to Eurocharged or Speedriven or somebody like that. The V12TT is protected with a LOT of protection mechanisms. Its very clever and rather complicated.
You can't over-speed turbos like you can other things. Turbos have torsional vibration behaviour and bending vibration behaviour, and if they clash you get a kind of flutter oscillation like an aircraft wing if you go too fast. Quick self-destruct.
Thanks for the input. Your cooling thread is exactly what I was talking about as being the road map, lol. It was a wealth of information. I may spend some time looking into alternatives, or possibly building my own tanks for something. I'm not the best welder (appearance wise), but I can generally make things airtight. The car will be down for a while getting all this stuff fitted/fabbed so I may as well tackle everything I can while it's already apart.
I beg to differ on overspeeding turbos. I've gone as far as welding wastegates shut and run cars for years that way looking to get the most out of stock turbos. The fact that you have pressure on the intake side preventing unrestricted runaway acceleration of the assembly tends to govern the speed within a reasonable range of what you'd see anyway...but that also depends on size relative to the engine (which I'm assuming is pretty small, given the response...does anyone know the actual specs on the turbo compressor and turbine wheels?).
Obviously the bigger the turbo, the more likely this will cause problems because of the tip speed on the wheels, and the greater effect any imbalance will have, but the short-term results have been phenomenal on every turbo I have run all-out like this and I have yet to have one come apart in 12 years of messing with turbo cars. OEM turbos are usually way overbuilt, I can only assume Mercedes has taken that to the extreme. I probably won't do it on the Benz though unless I get to the point where I am planning on upgrading turbos anyway (a pair of BW EFR 7670s would sure be fun...or even just have the stock ones rebuilt with billet upgrades). I should be able to get enough horsepower from more reliable methods to keep me satisfied for a while. Hell, the traction light already flashes at me if I floor it rolling 60mph. I kind of wonder why I even want more power out of it...I hardly put the pedal down anyway due to wheelspin.
That brings me to the question of limited-slip. Has anybody fabbed up their own spring/clutch type limited slip diff? Or a welded spare diff to swap in and take to the drag strip? I have been casually looking for a spare to play around with but it gets kind of confusing since all the parts yards and people on ebay list ANY S-class rear differential as compatible with the S600, which I am almost certain is not the case. Not really looking to spend $2-3000 for a quaife or other aftermarket one.
So you have the same tires all around now? How's that working out/what advantage do you see? I have huge tires on the front of my Buick and it's a nightmare to drive...every little bump in the road causes it to wander/pull. Drives like a dream with the stock size. Granted, that's an extreme example...going from 225mm all seasons to 315mm drag radials.
As far as tuning goes, I take a pretty conservative approach. I figure Mercedes spent countless millions of dollars developing the powertrain management for this car, and the professional tuners have the time and experience to know what works and what doesn't for the most part so I'm not trying to squeeze every last horsepower out there, I'd rather focus on charge cooling and if I *really* need more after all that, then wet nitrous with methanol as enrichment fuel is a no-brainer. It's not like these engines are trying hard at 50hp per cylinder. My Buick should be putting out more than twice that per cylinder when I get it back together here in a month or two, and I won't be too worried about it at that.
Received my spare intercoolers today. It's going to be a very tight fit and I'm going to have to get very creative with mounting/piping, but I think it can be done and still clear the hood. It's my birthday so I'll be having dinner with friends and won't get to work on it tonight.
Post pics !! The photobucket app makes it easy to paste pics from your phone into replies here
Mercedes actually severely detuned the v12 biturbo for traction , longevity and mpg/emissions . Unlike other cars where the automakers do a good job getting most out of the power, these cars were detuned to keep transmissions and axles from breaking ,and so they would get more than 8mpg. That's why it's so easy to get them into the 650hp range .
At that point though, more power really is useless as there's no good way to get it to the pavement
Post pics !! The photobucket app makes it easy to paste pics from your phone into replies here
Mercedes actually severely detuned the v12 biturbo for traction , longevity and mpg/emissions . Unlike other cars where the automakers do a good job getting most out of the power, these cars were detuned to keep transmissions and axles from breaking ,and so they would get more than 8mpg. That's why it's so easy to get them into the 650hp range .
At that point though, more power really is useless as there's no good way to get it to the pavement
I will get some pics up this weekend for sure. Probably Sat night or Sunday.
I think the whole "detuned" thing applies to most factory turbo cars. There's always another 20% or so "free" power if you have the octane for it...but in the case of the S600 that equates to a much larger number than on most cars since they make ~500 to start with. That's my biggest concern with upgrading...whether or not the trans and driveline can handle it (which I'm sure it will on the street, but on the track with drag radials or slicks, who knows). I'm not too worried about the engine.
I can't complete on the typing front, just a few quick comments for now:
Did you know the V12 intercoolers were already two stage? As well as being three times as big as the V8 Kompressor IC, they're also dual pass, though not quite like a radiator is dual pass. This is best described with a picture, but I don't have time. The coolers have a quasi-counter-flow configuration, which is like two sequential coolers.
The charge air goes through an 8 x 4 x 4 high temp cooler, then immediately through an 8 x 4 x 4 low temp cooler. All in the same unit.
Meanwhile, the coolant goes through the low temp cooler first, and then through the high temp cooler.
That's more efficient than everybody else's single pass coolers. Not many people know that, but I figured you'd understand what I was wittering about.
I'll bow to your experience of over-driving turbos, but I'd just wonder why Speedriven would resort to larger turbos for their high-tune engines when they could simply push the stock turbos harder.
Last year, I rebuilt the turbos on my first V12TT, and I'm full of respect for the engineering. I did take lots of measurements, as I recall being able to find very little about them. I had to pull them apart to find what size bearings to buy. Two bearings of course, not one. Anyway, they ARE small.
I agree about the need to get the IAT as low as possible, but you also need to reduce the filter flow restriction as much as possible. Turbos deliver an outlet/inlet pressure ratio, rather than an absolute outlet pressure, so the higher the intake pressure the better.
A few people have fitted LSD's, and all have raved about them. Look up all the posts by Racehorse on the subject. I think he did some great work on a cold air intake as well. A few people have done that with V12's, and gotten great results. However, they have CL600's to work on, which have more room at the front. We S600 guys are a bit stuck. I was just chuffed to get a second radiator in the front.
Having taken three years to get my Eurocharged engine working on-song, I drove around for while, revelling in NOT seeing the CEL, and then I broke my transmission. In fairness my car has just done 165k miles. I've just rebuilt that, and I'm refitting it this weekend while its dry, so I don't have much time to post.
Transmissions are usually OK for anything you can do with stock turbos, but you'll need an uprated one from one of the big tuners if you get very ambitious. The differentials are usually good. The S55, S600 & S65 all use a much bigger and heavier differential than the other W220's.
I run 275/30/20x10 all round, and it works very well. It really expands the dynamic envelope of the whole car. The ride is poor on concrete or broken surfaces, but its fine on good roads. 275/35/19x9.5 all round would be a good compromise. I'm sensitive to noise/vibration/harshness, and I don't like bump steer or tramlining. The steering is only slightly compromised, but there's an improvement in accuracy, directness and feel, and overall I think its much better.
I'll be following with interest.
Good luck,
Nick
Last edited by Welwynnick; 02-13-2016 at 05:34 AM.
I did not officially "know" that they were dual pass, but I was kind of guessing they might be from the coolant piping configuration (same side of the core). That's great news...I'm a huge fan of the efficiency stacking of series intercoolers. It makes so much more sense to continuously expose the charge to as cool of water as possible.
Thanks for the turbo disassembly pic. They are a work of art compared to most factory turbos, that's for sure. They ARE still journal bearing though? I was wondering. The integrated bypass valve and wastegate are setup just like my Borg Warner EFR on my Buick, so I assume these may have been an oem precursor to that line of turbos.
As far as why speedriven hasn't pushed them further...who knows? You get into some really crappy thermal efficiency numbers when you run off the map like that, so if you don't have excellent intercooling and anti-knock measures you are in trouble and won't make more power anyway...and also you risk exploding a wheel. If I was a shop with a good name in the community I don't think I'd be doling out that advice either. Plus, how can they make money saying, "no, you don't need our billet turbos, you can crank yours up some more". There are other countermeasures to shift the compressor map as well...I mean the pre-turbo water/meth injection doesn't net you any gains for charge cooling overall because you end up condensing it back out at BTU expense in the intercoolers, but it can significantly reduce the temperature and increase density at the compressor inlet and during the compression process which increases mass air flow through the compressor wheel at the same speed.
Fact of the matter is the things are absolutely still pneumatically actuated like any other turbo out there and it is an extremely simple matter to take that control away from the computer and set a boost controller or even just plain let them run wild. If nobody's messed with that, then I'm all that more excited to give it a shot once I've got the supporting mods in place.
I know all about absolute inlet pressure and pressure ratios...my Buick is twincharged. I've got a very large turbo feeding a very large supercharger. Initially, response was not what I anticipated. Come to find out, a large overdriven supercharger doesn't like sucking through a 2.5" turbo outlet so I'm having to develop some bypass valving for the initial throttle snap. Don't get me wrong, it was still stupid quick, but just not as immediate as 25psi of supercharger boost should be. I ran the numbers on it and I believe I was losing 2-4psi of inlet pressure from atmospheric by drawing through the entire system. Of course as soon as the turbo builds positive pressure it more than overcomes those losses, but that takes a fraction of a second longer than it should when your initial supercharger boost is 2/3 of what it should be from the inlet restriction. I don't have any current pics, just one from when everything was a huge mess under the hood/working out bugs, but I will post it up just for grins.
I may have to try the rear tires up front and my Buick's drag radials on the back with some custom hub-centric adapter spacers. That would give me a lot more meat on both ends. The custom spacers are cheaper than new tires, lol...they wouldn't match but I'm not too worried about cosmetics when I feel like going fast, and if I like it I can make a more permanent change. Actually, they wouldn't be too far off if I painted the AMG wheels black...it's a 5-spoke black Mustang cobra wheel, lol...thinner spokes but not an entirely different style.
Last edited by ZephTheChef; 02-13-2016 at 06:15 AM.
Got the new pullies and belt and stuff in, so hopefully I'll get back to work on it some this weekend and can post some pics of intercooler placement ideas and the exhaust cutouts and such.
Ok, so I was feeling ambitious last night. Replaced my front wheel bearings (one was just barely starting to make noise) and then got to work on fabbing up the new downpipes with the exhaust cutouts. I basically Just cut the cats out of the stock downpipes, and replaced them with 3" pipes that Y into electric cutouts. I didn't get them wired yet, and I am sure I am probably going to have to mod some of the undercar plastics, but I'm happy to have it done...I have missed driving it.
Bigger turbos, more fuel, custom tune. Just like my lsx turbo. You've got the knowledge, a pushrod engine is still a pushrod engine no matter the number of cylinders or country of origin. Imho
Bigger turbos, more fuel, custom tune. Just like my lsx turbo. You've got the knowledge, a pushrod engine is still a pushrod engine no matter the number of cylinders or country of origin. Imho
Does anybody have any flow data/hp limit on the stock fuel pump or know the actual injector flow rate for sure? I may have to at least flow test the pump. Really thinking about going E85 if I can sell my stealth for a reasonable price.
Kind of hoping the pump is up to the task...I don't really feel like removing the tank to modify it for twin 450s or a big weldon or something. If nobody knows I guess I'll just have to do a flow test.
Hmm might be a bit late to this, but i'd say since you got a 2003+ S600 with the M275 biturbo engine, just flash the ecu for a higher boost. That'll for sure give you a good 70+ HP.
Hmm might be a bit late to this, but i'd say since you got a 2003+ S600 with the M275 biturbo engine, just flash the ecu for a higher boost. That'll for sure give you a good 70+ HP.
I ordered and paid for an ECU and TCU tune before I even physically picked up the car. So yes, you're a little late for that, but I appreciate the input!
Strongly re-thinking my plans. I just can't ignore the benefits of switching to a better primary fuel. Especially since the best gasoline available around here is 91 octane and I KNOW the car is struggling with that/going into low octane maps. Problem is, Jerry says his tune hits 76% injector duty cycle...so they are already basically maxxed out (since most people don't push injectors over 80%) and that would require 99% if I just switched to E85...without considering my other modifications which will surely push it over. Secondary problem is I have no idea if the stock pump will even max out the stock injectors.
Has anyone flow-tested the stock pump at max pressure? If not, I guess I will do it. Also, who has converted to E85? I know there was one gentleman that did it, but I never found any details on his setup but I believe he did it on stock injectors...which the math just doesn't support on my tune. So IF I have to buy injectors, cost doesn't change much with size, so I'm not settling for being limited to E85...I plan on sizing them for up to 1000HP on straight methanol so I can throw in a fuel cell and switch to straight meth and a more aggressive tune if I want to take it down the drag strip. So that would be 12 x 1300cc injectors. 4 gallons per minute fuel flow, lol. Yikes!
Ok, so that plan isn't happening. Apparently Jerry has zero control over injector scaling...so if I do get injectors they will just have to be appropriately oversized for E85 and not actually tuned for. Bummer.
I need to flow-test a stock injector to verify the size I need, but if they are in fact 39 lb as I have been led to believe, then a 52lb/550cc replacement should be perfect.
Ok, so for anyone who is interested, the stock injector flowed out at 350cc/min static flow @ 43.5 psi. So basically they are 33.3 lb injectors, not 39 lb. I have yet to test the pump flow, but I will be ordering 12 450cc injectors and hoping for the best. If I find out in the meantime that a pump upgrade is in order then I will cross that bridge when I come to it.
It's probably out of the spec of your plans but there are some good standalone systems on the market that will really allow you to get more power out of the motor, far more than any of the tuning companies can get with the packaged tunes. I love the Eurocharged/Speedriven/etc tunes on the MyGenius for simplicity and install them in almost every car I sell/own but when you want to go all out, they can only change so much. There just isn't enough freedom to really tune, like you found out with injectors. A standalone kit will allow you to properly manage larger injectors, boost pressures, etc.
Take a look at a killer chiller. You can probably come up with something on your own to accomplish the same task coupled with a larger reservoir somewhere in the car. Meth injection helps out quite a bit too. IAT is killer on these.
02-11-2016, 11:55 AM
