Oil & PS Coolers, Aux rad delete, & Intake snorkel

[koolade9]

Over the past week, I've been making some changes to the RS. I switched up to a (much) larger Setrab oil cooler, bigger power steering cooler, removed the auxiliary radiator, and fabbed an intake snorkel.



Cliffs: do the aux rad delete and intake snorkel...significant difference!!

So on the track, I was seeing oil temps of 275 after several long sessions at high rpm. Other cars hit higher temps, but this was still too high for me. The solution was a larger oil cooler...in order to install a larger heat exchanger, you need to upgrade the power steering cooler as well...from the factory it's in front of the oil cooler.

Factory units for reference...


For a PS cooler, I picked up a 7.5"x12" kit from Jegs for $50. Only other parts needed are a pair of 3/8" male to 3/8" male hose barb adapters.

I picked up a Setrab 50-172-7612. Dimensions: 8.27"x22.13"x1.83". Weight - 5.3lbs. I was able to re-use the factory oil cooler lines, although I want to replace them with new (real) SS lines... The factory lines are a plastic loom with a stainless steel mesh over it...I was unimpressed to say the least. I used a set of -12an compression fittings to get a solid seal. Then fabbed a set of brackets out of aluminum and attached them to the bumper core support. The lower brackets attach to the factory brackets. I re-used all the rubber mounts for the factory coolers to keep as much vibration out as possible. The unit is a very tight fit, and I had to remove a 3"x1" chunk of the core support as well. It was a PITA install to say the least...



While I was in there, I removed the auxiliary radiator as well. I just re-used one of the factory hoses to bridge the gap. Made a new bracket to hold the factory air ducting in place, then routed a 3" hose from the airbox (removed the flap) down to the front grill. Then molded the factory duct to route all air into the air inlet. No pics of that yet, it needs finishing work. Also need to do some mid-summer testing to make sure there are no negative effects to the cooling system in 115deg temps...

As for results, I never had any power steering problems that I knew of, but more cooling never hurt anyone. The oil cooler is working well so far...I'm pretty sure the RS has a factory oil thermostat, as it warms up at the same rate (or at least close) as the factory unit. I obviously need to do more high-heat testing (next track day in a month or so) to see how well it's really working.

The biggest change I saw was due to the intake snorkel. Better throttle response, consistent power everywhere, and the pull from 5k up is far stronger then ever before. It's not making 'more' power...but making what it should The oil cooler/ps cooler are a pretty involved install...but word on the street is another company is making an off the shelf kit



What I recommend hands down, is removing the aux radiator and run an intake snorkel down to front lower grill. It's relatively easy, very cheap, and very effective!

[beemercer]

that oil cooler is sex.

How much did that core run? I'm looking to add an oil cooler to my A6, nothing that big but I want something quality.

Also -12AN? How big is the stock line?

[koolade9]

that oil cooler is sex.

How much did that core run? I'm looking to add an oil cooler to my A6, nothing that big but I want something quality.

Also -12AN? How big is the stock line?

The Setrab units aren't cheap. Mine was around $550, I know they have slightly smaller units for around $250-350, but the I/O configurations vary. The stock lines on the RS are -12AN. I bought a set of -10 fittings first before I found out that info...so if you decide to run -10 lines, I've got a set of Earls compression fittings and Setrab m22 fittings in -10...never been used

[beemercer]

^damn the -12 must be like fire hose.. I was actually planning on running -10 since the fittings on the relocation kit are 1/2" NPT so I think the -10 would be a good match.

I'll probably go with a different cooler core though, I don't road race but my oil temps got pretty high at the last rally so I just wanted something mild.


Thanks for the info though

[NY07RS4]

Awesome stuff, looking forward to more data on the testing.

[rs4 tony]

do you have an airfilter at the end of the snorkel? what happens when your on the highway and it's raining, you suck up water from person infront of you I'm sure it gets forced up the. snorkel but will it stop At the filter?

[dmaxben]

Setrab makes beautiful coolers. Yes, they are expensive, but you wont find a better cooler out there. I replaced the factory tranny cooler on my truck with a bigger Setrab cooler and the second I pulled the thing out of the box, you can just feel the quality (heavy, no sharp edges, smooth paint, etc) when you pick it up...

[rs4 tony]

Setrab makes beautiful coolers. Yes, they are expensive, but you wont find a better cooler out there. I replaced the factory tranny cooler on my truck with a bigger Setrab cooler and the second I pulled the thing out of the box, you can just feel the quality (heavy, no sharp edges, smooth paint, etc) when you pick it up...

since it's bigger, does this mean it needs more oil when doing oil changes?

[dmaxben]

since it's bigger, does this mean it needs more oil when doing oil changes?

I suppose maybe a little more? Granted, this isnt on my S4, its on the trans in my truck which holds 5 gallons of fluid so to be honest I really didnt notice if I had to add any extra fluid when I put the Setrab cooler on. The difference probably wouldnt even register on the dipstick because its such a small amount in comparison to the total fluid volume.

Basically, in my post above I was merely agreeing with Koolade on how nice/high quality Setrab coolers are in general...

Ben

[koolade9]

For the RS, it probably holds an extra .5qts I'm guessing... So far my oil temps have been down 5-10deg while daily driving. I didn't expect that, but I'm stoked on it. The intake has dropped IATs to a 5-6deg C delta (from ambient) vs. 10-15deg C prior.

do you have an airfilter at the end of the snorkel? what happens when your on the highway and it's raining, you suck up water from person infront of you I'm sure it gets forced up the. snorkel but will it stop At the filter?

The snorkel is plumbed in the factory 3rd inlet behind the airfilter. There is also a screen at the lower inlet to keep larger particulate out... As for water...last of my worries...I'll need to be in 3' of it for it to really affect the motor. FYI, small amounts of water (think rain) isn't bad for an engine (look into water injection systems ), and I didn't block off the other two inlets, so I'm not worried at all about hydrolock if I ever have to drive through a flooded road.

[Ill 3.0]

For the RS, it probably holds an extra .5qts I'm guessing... So far my oil temps have been down 5-10deg while daily driving. I didn't expect that, but I'm stoked on it. The intake has dropped IATs to a 5-6deg C delta (from ambient) vs. 10-15deg C prior.

That's amazing. What are the daytime temps where you are now? mid-high 80s? Not even really that hot. Nice work as always. For all the R&D Audi did on this motor, guess they cut the cooler corner.

[rs4 tony]

perfect. thanks

[koolade9]

That's amazing. What are the daytime temps where you are now? mid-high 80s? Not even really that hot. Nice work as always. For all the R&D Audi did on this motor, guess they cut the cooler corner.

70s at night, around 90 during the day...give it another month or two and we'll hit 110 or so. I think the factory cooler does a good job for a daily driver with the occasional 'spirited' run. but if you track at all, or really push the car...it's not enough for my liking. Either way, I'm no longer worried about it

[mickf29]

Do you have a part number for the JEGS $50 cooler? Is it a Derale?

i received the Setrab main oil cooler today, well my neighbor got it as I am still on travels. I need to get the AN-12 fittings and get the parts for the PS cooler and I will be ready to install. Shoot me a link of the cooler you picked up for power steering, thanks!

[mickf29]

Nevermind, found it! also ordered all the fittings from JEGS for both coolers. Gonna do some hacking this weekend!

[RS4POWER]

Awesome work Blake!

[mbgt72]

Very nice upgrades there, I'll be interested to see more pics.

[WinterRunner]

Awesome work like always! A few pics of the new snorkel airbox mod would be great.

[Novtec1]

oil cooler is pretty sick....i like