Now for IATs (B8 S4)

[B8S4OZ]

Hi All,

Been a while but I've been hard at work on my B8 S4 project.

I just wanted see if the consensus agrees with me that the single best setup (putting aside divorced and CWA upgrades and other piping modifications) is to

1 - Larger heat exchanger (to replace the front smaller one)
2 - Remove the secondary side heat exchanger?
3 - CWA Upgrade
4 - Meth
5 - Various piping mods like Audi Owners C7 show's us on his videos
6 - ?

[RoofRails]

Hi All,

Been a while but I've been hard at work on my B8 S4 project.

I just wanted see if the consensus agrees with me that the single best setup (putting aside divorced and CWA upgrades and other piping modifications) is to

1 - Larger heat exchanger (to replace the front smaller one)
2 - Remove the secondary side heat exchanger?
3 - CWA Upgrade
4 - Meth
5 - Various piping mods like Audi Owners C7 show's us on his videos
6 - ?

This list seems good to me. The base of your cooling mods starts with a good HX. I went with the Mercracing S7 model which as far as I know Is the highest capacity HX on the market and paired it with a CWA 100 that is de pinned to run 100% of the time. I recently added wmi as a fuel supplement and have seen some benefits to cooling as well. The biggest being the system is harder to heat soak by doing back to back pulls. It knocked a few degrees C off of my heat rise delta in a 1/4 Mile pull as well. The single biggest thing you can do besides the items on your list would be to divorce the system and run a high water % mix during the warmer months. I haven't gone that route yet but it is very effective from what I have seen.

Sent from my SHT-W09 using Audizine mobile app

[Fresh.S4]

Cwa 50 @ 100%
Divorced @ 99% water.
Removed side hx
Install small upgrade hx (the original small merc hx)

If I can keep WOT under 165*f
And cruising temps between 17-20*f above ambient in 90*f + weather in 1500+ DA, then you shouldn't need major upgrades either lol.

Keep it simple and don't over complicate things and it will work as intended.

[LowKeyLoki]

What are the benefits of removing the side heat exchanger? I’m ready to upgrade the stock one but am curious wouldn’t you want to keep the smaller exchanger for more surface area for coolant to flow through?

[Fresh.S4]

watch Chris' youtube. hes got better explained cooling videos than Cameron

https://www.youtube.com/channel/UCaV...WG-YjIw/videos

theirs a video that discusses the benefits of running dual hx (and it kinda makes sense). Like it acts as a last minute charge after it leaves the big hx and before it hits the bricks.
The benefits of removing the side hx are to increase pressure/flow. I removed mine so I can attest that even on a cwa50 the flow/ pressure increases.

before you go out and buy a bunch of stuff, just divorce your setup and a MOSTLY distilled water (as long as it doesnt get into freezing temps where your at) and see how you like it.
I dont plan to ever purchase a bigger pump, in fact what I did was now I added a secondary cwa50 right before the hx.
summer is over here in hot as fk cali so I cant test to see any cooling benefits other than giving me more flow/pressure. I also have the velocity brick adapters to run larger 3/4 lines which I might install because im not in a rush and feel like my temps are remotely bad. theyre awesome!!

[LowKeyLoki]

Yea I am running mostly distilled about 70/30 rn, doesn’t get to far below freezing here in GA. I haven’t had any issues thus far with IATs even in the GA summer of 90+ heat. From my logs I’ve never really seen my IAT over 50C unless it’s multiple back to back pulls. Debating wether to wait to upgrade the stock hx now that’s its winter. Honestly might not even upgrade it since I’ll probably never go beyond stg1 unless I have the car for another 5 years. Are there any after market small high flow hx that’ll fit where the small hx sits? Seems like a waste of space to remove the small hx when it already has air ducting and lines for that spot.

[Fresh.S4]

The smallest would be one of the generic ones from merc that goes behind the crash bar.

Honestly the oem is probably good as long as you aren't doing back to back to back to back to back etc..

It's probably good for maybe 2-3 hard pulls and then just cruise a bit to lower temps and do it again.

Take a water bottle and leave it outside and see if it freezes. If not more water! Lol.

[B8S4OZ]

Cwa 50 @ 100%
Divorced @ 99% water.
Removed side hx
Install small upgrade hx (the original small merc hx)

If I can keep WOT under 165*f
And cruising temps between 17-20*f above ambient in 90*f + weather in 1500+ DA, then you shouldn't need major upgrades either lol.

Keep it simple and don't over complicate things and it will work as intended.

It sounds like removing the secondary OEM hx is the go. I doubt it would be very efficient, more of a bottle neck. I would prefer it all to flow through the larger hx that I've installed. Did you see much benefit from running a secondary CWA50? I know the CWA150 is out now and with the correct wiring harness etc.

This list seems good to me. The base of your cooling mods starts with a good HX. [/URL]

Yeah, I have a CTS Larger HX. I'm able to use my tune (034) to turn the pump on to 100% but it's so loud I rarely use it. However, I'm not doing back-to-back pulls at all. Thinking about tracking it though so wanted to get it sorted before then.


Temps, where I live, can be anywhere from -5c to +40c. Currently running 50/50 mix.

I was looking at the Velocity AP piping kit also. However it's super expensive for me in Australia. - https://www.scuderia-autoart.com/p/a...TFSIECU-SCPORT