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W202 230K Sport manual & a few non Merc's
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vw gtd's are no problem for it, same for these 2.3l ecoboost mustangs (those are very popular here)
Oh, I'm not surprised in the slightest. The power you have now in knocking on Golf R performance I'd suspect and those are 1500+ kg . As for the GTD, they're quicker than I imagined, reckon they've got plenty of torque and 184 PS is not to be sniffed at. Yeah, I've seen a good few of those Ecoboost Mustangs here, all down to annual road tax and emissions ratings. Really, four pot's are not right for such a car, it's just plain wrong. It's just a matter of go big (V8) or go home when it comes to the Mustang.
 

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1998 SLK 230
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Ndrmini this was my stock boost map

2603954


this is my current boost map below...
for people that don't know 0 means fully open bypass valve, and 255 means fully shut bypass valve (full boost).
it is plotted against RPM vs LOAD

it ramps on very aggressively and loves to spin the tyres!!
2603955
 

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I tried playing with the boost maps (added 10% and even more) to see what the effects are and I went back to stock,
in my case: (manual transmission)

pro:
-gas pedal is more sensitive, it gives a sprint booster effect (gas pedal tuning)

con:
-makes cruising and partial throttle driving (just on the edge of boost) difficult and the fuelling is completely wrong

-it doesn't make the car faster/ more powerful compared to the stock boost map


This mod is not for me, I also think it works better on an auto box, my drivetrain is already very rough and it makes the car feel like there is something wrong







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1998 SLK 230
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Thanks for sharing. its true it could be difficult to drive in manual and feel jerky, but yeah i am a fan of it on the auto box :)

any more tuning with the water meth kit?
 

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no new gains with the water/meth tuning at the moment, adding even more timing results in less power but no signs of detonation (advancing beyond the optimal point of ignition) the setup is pretty much perfect now

time to find something else to upgrade i guess (maybe cams but it will cost some torque)

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W202 230K Sport manual & a few non Merc's
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Ndrmini, have you any concerns about removing the S/C rotors coating (a Teflon coating from what I know)? And if the W/M does remove it what issues do you think it may cause?
 

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I think that there is a bigger chance of stripping the coating off by spinning it at 16k+ rpm generating heaps of heat then by atomizing a fine water/meth mist in front of it to keep it cool

i could be wrong, I'm not an expert on rotor coatings but so far it has been holding out great



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W202 230K Sport manual & a few non Merc's
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I'm in the process of wiring up my W/M injection kit. What I need to know which wire is the MAF signal wire.

Now, I've searched the forum (difficult with the new setup) and did find a thread on 'clamping' the MAF but there was a little confusion due to pre and post face lift models.

So, can somebody please clarify for me on a pre face lift which wire is which. Thanks in advance.

1. Yellow/White
2. Red/Blue
3. Brown
4. Yellow/Brown
5. Yellow/Green.




2606331
 

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SLK R170 230k 1998
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I have water methanol installed in my SLK230, it did not have much gains with my my porterd/stacked pulled supercharger. With my turbo installed, I had about 10whp gain. The real advantage is it makes higher boost safer.

I have tried it in 2 locations:
1. before MAF (about 10 inches away)
Only thing this did was mess with the MAF and make the car crazy (jumping between lean and rich sort of). It did not bring down the IAT, maybe our IAT sensor works different.

2. After MAF, and before IAT
Had relocated MAF further up, then tap the water meth behind it, and another MAF between it and the TB (wiring only to IAT of the MAF).
Change in IAT not rapid, takes aw211 long spray to have few degrees drop.
So I concluded our IAT sensors dont work well with water/meth

3. After MAF, 6 inches before TB
-Best location, nothing to sense IAT with water/meth, but 10hp gained without changing the tune. 15whp after retune.
 

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1998 SLK 230
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some more information as to why you may want to run water methanol.

these cars pull a LOT of timing quite aggressively as the intake temps go up.

the below is from WIS... 35c intake temp and it pulls 3.5 degrees.... once at 65c intake temp (which is pretty easy to do depending on climate and intercooler), it pulls 9.5 degrees!

2606552


even with no tune, this will stop the car pulling timing out
 

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+1 @Subby_ it is very noticeable

the only proven way to inject before the maf on these cars is to inject pre blower, intake temps will almost stay the same during boost

pro:
-it will make the blower run way more efficient
-it cools down the intake pipe close to the exhaust
-the maf wont go crazy (unless you inject to much)
-intake temps will be just above ambient under boost

con:
-only inject w/m during boost or it will puddle in the intercooler
-the amount of w/m has to be dosed carefully (180cc nozzle seems to work very good)
-place check valves very close to the nozzles so it stops spraying as soon as boost stops
-it might strip the blower coating (mine is still fine)
-only use progressive w/m kits (mostly referred to as "stage 2") , the cheaper on/off kits are useless



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SLK R170 230k 1998
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some more information as to why you may want to run water methanol.

these cars pull a LOT of timing quite aggressively as the intake temps go up.

the below is from WIS... 35c intake temp and it pulls 3.5 degrees.... once at 65c intake temp (which is pretty easy to do depending on climate and intercooler), it pulls 9.5 degrees!

View attachment 2606552

even with no tune, this will stop the car pulling timing out
I'm from Malaysia, and the ambient temperature during day time is 35 to 40°C. IAT on light throttle is about 45°C, WOT goes upto 60°C.
I guess my ignition is always retarded... and is it possible probably the water meth could never bring it down sufficiently.
 

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1998 SLK 230
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I've seen cars (c32/e55) etc which run a higher ratio of water to methanol (90% water/ 10% methanol) to focus on cooling only. their goal with water methanol injection to prevent the car from pulling timing and maintaining power.

It should be possible to go below ambient temp with water methanol. I think for the HP of most modified R170 a cc nozzle of 160-190cc should do this.
 

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1998 SLK 230
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say you had a 270hp r170... 5hp is roughly lost per 1 degree of retarded timing

35c -> 44c 3.5 degree timing removed = 17.5hp lost = 252.5hp
45c -> 64c 6.3 degree timing removed = 31.5hp lost = 238.5hp
65c + 9.5 degree timing removed = 47.5hp lost = 222.5hp

so you end up back at around 222hp at the crank which is the same a car with just a crankshaft pulley... also explains why people who spin the s/c very hard 16,000rpm dont make any more power... it simply generates tremendous heat in the 3rd generation roots supercharger
 

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1998 SLK 230
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interesting read... the 2018 porsche gt2 rs uses an intercooler spray to keep it cool

Water for the air cooler: Innovative additional cooling of the charge air
Intermediate charge-air coolers reduce the temperature of the process air heated by the turbines through an innovative feature: A new water cooling system sprays the heat exchangers with liquid during load peaks. This lowers the gas temperature in the overpressure range by up to 20 degrees more than would be possible using the airstream alone. By delivering this reduction in temperature, the system ensures that the flow of charge air is thermally stable – even under extreme conditions. The water cooling system comes into action when, among other factors, the temperature of the process air in the intake manifold is above 50 degrees, the driver depresses the accelerator pedal by more than 90 per cent and the engine is running at a speed in excess of 3,000 rpm. The system is supplied by a five-litre tank filled with distilled water. With this system, the vehicle is able to achieve extremely fast lap times – such as on the Nürburgring Nordschleife – with maximum power output, even at high outside temperatures.



and the BMW M4 GTS uses water injection (into manifold) with water only to cool the intake charge (no methanol to boost octane).
 
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