Well, an hour or so later I finally finished reading that thread on the r170 forum... Some really interesting stuff going on over there. I might consider purchasing this intercooler, and doing this some time in the future. Definitely a great deal on that intercooler. Is it still around $50 dollars?

 

OK,

i just went out tonight to measure the intercooler on the Coupe. The core is around 25" in length, a bit longer than the SLKs. From the middle of one of the elbows to the other is around 29". On the inside of hose on the elbow there is about 1/2 - 3/4" of slack room. All in all, the IC Steve used should fit, if anything a little short, but there should be room to move, and depending on the elbows you use, you should be able to fit it perfectly without any modification, if not just use longer elbows or extend one of the ends. I already went ahead, took the plunge and bought the intercooler, I am about 90% sure it will fit. If it does not fit, I will make it fit or resell it on the SLK forums. I'm having gakz on the SLK forums buy me the parts he used for his install and I will let you guys know how it goes when everything arrives, should be about 2 weeks. In regards to the parts needed, you will need 4 clamps because unlike on the SLK, the coupe's hosing that goes to the elbows does not have a rubble coupler like on SLK, it has those weird metal clips that hold the elbows mounted on the IC directly onto the house that leads to the MAF.

 

Owning both cars, a C230 and SLK230 and having the IC out on both side by side, they are totally different. Also, I can almost guarantee you will lose power right off the bat because it will not flow as well as the factory IC and you'll lose pressure. The best way to determine this is to do a dyno run before/after like I did, the cheapest way is to buy a $15 boost gauge and see how much max pressure you have at WOT before and after, a 1/2 PSI drop could be a 8-10 HP loss. I got 1 PSI pressure loss on the Renntech and 1/2 PSI pressure loss on the Ractech IC.

OK, but say you magically make an IC that flows the same as the factory IC but keeps the intake air temps cooler, what's the most you'll gain? Under the most extreme conditions on a stationary dyno (not moving at 80mph on the street where you have great airflow over the IC), I sprayed cold water on the IC and under the most extreme conditions, say after doing 3 or 4 back to back dyno runs, I was able to reduce the loss from a typical 12HP to 7HP but keep in mind, you will never get your IC as hot on the street as indoors on a dyno. In real life, and you can see this my looking at IAT on your OBD2 scanner, the IC runs about 20F higher than ambient air and during hard accellation you can get it to about 80F over ambient but it cools down so quickly on the road that even if you drive a total lunatic it will probably hover at 40F over ambient most of the time. Sure, if you can get the temps down below ambient and keep flow the same or better you will gain HP, but you'll need to spray CO2 or NO2 through the IC and that's a good waste of NO2 unless you are racing. If you just need to drag race it at the track, do what most racers do, put an icepack on the IC

 

Yeh, the IC on the C coupe is the same as used on the new R171 SLK, and is bigger than the one on the old SLK, as I saw from the EPC.
Where I live it just doesn't get that hot, enough for me to bother with this...
can't wait to see what happens Dachigga.

 

I will keep you all posted.

 

Owning both cars, a C230 and SLK230 and having the IC out on both side by side, they are totally different. Also, I can almost guarantee you will lose power right off the bat because it will not flow as well as the factory IC and you'll lose pressure. The best way to determine this is to do a dyno run before/after like I did, the cheapest way is to buy a $15 boost gauge and see how much max pressure you have at WOT before and after, a 1/2 PSI drop could be a 8-10 HP loss. I got 1 PSI pressure loss on the Renntech and 1/2 PSI pressure loss on the Ractech IC.

Seeing how the supercharger is positive displacement, having a post SC drop in pressure would tell me that the [new] intercooler is actually less restrictive. Boost is simply a measure of how INEFFICIENT your intake (post supercharger) really is. The ONLY number that matters in that case is flow (cfm, lbs/min). A pressure drop in the case should yield lower supercharger outlet temps. There are many variables in a system so it is difficult to say how much (if any) increase in power this would yield.

Also, did you test the different intercoolers on the dyno? It sounds like you only tested the one intercooler and sprayed it with water. So that would tell me that you don't have proof that the other intercooler's dropped power like you are implying.

 

Haha, the only number that matters is power, every other number is just fluff. I will be happy to take a bet that you will lose power.

I've tested 2 ICs, one made by Spearco for Renntech, looked very nice, shiney with Renntech painted across it. This was a huge IC, lost the most PSI, lost the most HP. BTW, we tested on two C230's, one with auto trans and mine. The reason we tested is because a fellow forum member put an ASP pulley and IC on and it didn't feel like he gained anything. We dyno tested to find out what was going on and found out it was his IC. Took it off and the car went back to normal. Dynoed my car with the same setup and same thing, IC was sucking the life out of my motor. We checked for leaks and it was tight, just ineffecient design.

The second one was made by Racetec. They make a very highly successfull IC for the Audi/VW crowd. It was actually custom fabricated by a team that makes CART race cars here in the O.C. It was a very impressive shop with a half dozen race cars in various states of construction, a used one being refitted for a new driver and 2 NASCAR cars being rebuilt. It was a very nice IC, smaller than the Renntech and a very fluid design with minimal welds. The core was highly regarded design made in germany. It was not as bad as the Renntech, it lost about 1/2 PSI with porportionally power losses.

My last tests was to use IC misters using a controller made in Australia. This proved to be the best as it didn't lose any pressure or power and under extreme conditions, it actually reduced power lose by 5HP but these conditions were so extreme, unless you race, you will never come across them. We also tried vapor injection, this is where you stick a very fine mister in the intake and use a high pressure pump to vaporize the water/methanol mix. Made by a company in the UK, think it's call the Aquamist. It too reduced HP losses at high IAT by about 5HP on my buddy's SLK230 (same motor as my C230K). The reality is, that even in extreme cases where gained 5HP, it was not worth the hassle of refilling the water tank and the maintenance of it should something go wrong.

Now if your goal is to make something shiny and pretty and there's no power expectations, then go for it, just remove the plastic grill material so we can all see it, maybe put some LED lights behind it to make it glow.

 

I don't give a damn about making things look "nice" if it is going to make power. I am baffled that an OEM IC would be so much better than the "race proven" IC's that you spoke of. I am no layman when it comes to boost, adiabatic efficiency, or flow rates. That is why I ask and that is why I challenge. Where did you test the pressure in the intake system? Did you test IAT's ever with the different IC's? Does the logic in my previous post make sense as to why your results seem counter-intuitive?

I am also familiar with the water/meth injection. It is a good way to get that last bit of potential out of a system that is already running on the edge of detonation but the results would be less in a low boost system. There are a few companies in the states that now make stand alone injection systems that are very good quality. Did you tune for the meth?

As I mentioned before, there are a lot of variables that have to be taken into consideration when putting together a forced induction system.

 

Yes, monitored IAT during all tests and these larger IC's definately made the IAT cooler by a lot but not enough to compensate for the loss of pressure. I measured pressure at the throttle body, t'ed off the vacuum line there.

We did try some chip tuning but there wasn't enough gain to make it worthwhile and we weren't going to lie like some companies and make up gains. The water vapor injector was on an older motor that was already pinging with the added boost from a pulley kit so it helped with that.