I haven't really seen anyone post on this but, I was wondering just how much psi the stock top mount intercooler can handle? I also would like to know if anyone sells aftermarket top mounts. I really wanted to avoid doing a front and try to keep the car semi original. Thanks guys

 

Normally at 10 psi, the air temp will be hovering at 155f at 90f ambient. Thats after 5 quarter mile runs at the tratrack. 155 is way too high for me, highest ive seen mine go was 170f at 12psi lol. ARC makes thicker tmic for the fc

 

There's always auxilary injection....Sen2two has an awsome thread on his modified top mount

 

There's not really a limit to the pressure you can put through it. But as overall pressure increases, pressure drop from inlet to outlet will increase, and cooling ability will decrease. If you're talking about using it with the stock turbo, limit your boost to about 12 psi. But ONLY if you have the proper fuel/fuel control modifications to support a boost increase over stock.

 

I've got a Greddy FMIC. For comparison, when measured at the elbow the highest IAT I will get is about 50-53C which is 122-128F. That's when it's really hot outside and the car is moving enough to circulate air. It can spike higher than that if it's really hot outside and the engine is idling with the hood shut.

Usually with a FMIC the IAT is 40-45C max which is 104-133F.

 

in short after approximately 12psi of pressure you will feel the bottleneck effects of the TMIC. some people like BDC have pushed 25 psi through it and put down around 450+ WHP through it but it is highly NOT recommended even with race gas/auxiliary injection to put more than about 15 psi through it, otherwise it isn't doing it's job and becomes a liability.

there is companies like ARC that have an aftermarket TMIC that are slightly more efficient but they are still small modular bolt on upgrade intercoolers and only barely raise the limits stated above.

 

pressure drop at stock boost on an S4 is about 1.1psi. efficiency is only about 68%. both of those numbers are kind of so/so, and will get worse when turning up the boost.

 

The price of the ARC tmic isnt worth it for such a small gain. You could get a NPR? intercooler and with a little bit of work place it where the hood latch area is. Piping would be simple and short, it wouldnt have that front mount look so it would seem semi original. OR you could do what Sen2two did. If your running a upgraded turbo i would get rid of the tmic asap. In general i would get rid of the tmic, talk about heat soak!

 

once you can start datalogging and seeing how bad the heatsoak is, a better IC is not far off. I originally planned to run the TMIC to 12 psi or whatever I could get out of the stock turbo. Once I actually figured out what that little gremlin was up to......fmic this weekend!

 

Greddy also makes an aftermarket TMIC.

 

Proper ducting for everything also helps a good amount.

 

this info is a bit inconclusive in my opinion, whats the safe amount to run with an upgraded fuel system and ecu, conservatively (no chance at ALL of blowing the engine), id like to run 11-12 psi since my fuel system/ecu is good for it, but the top mount just seems too weak.

I've got an rtek 1.7, walbro 255lph, 720cc secondaries, the exhaust is 2.5" downpipe to 3" midpipe to 2.5" once again, stock s5 turbo with ported wastegate, stock airbox.

 

You need an EGT gauge or wideband and get it tuned .
Just a glance at the gauge you'll what it's running instead of guessing.
You cannot just install an rtek (never seen it tuned) or using someone elses map/ or base map and expect to be safe. You'll be amazed how far off you are (a/f wise) using someone elses map with the same upgrades.

 

Bigger turbo/ higher boost generates heat.
Anytime you increase boost/ turbo, you need cooling and only way is a bigger IC.

 

The question was about the top mount not the other stuff.

My fuel system /ecu setup was designed to effectively run Max boost on the stock Turbo, that's why I bought it.

I'll have to do more research on it, I do remember seeing one guy running this setup that blew his engine at the track running 12 psi on the stock Turbo, so would the top mount inter cooler be the cause or the fuel system?

I'm just trying to figure out how much boost to run , I've got plenty of time to research since I have to break the engine in.

Edit - just read an old post by rotaryrocket88 stating he was running lean on this same setup at 12 psi and even at 9 psi when he lowered his boost.

Does anyone else have experience running this setup? Guess ill need to get a wideband as vanhalen suggested before I start getting into boost levels beyond stock, I hope I don't run lean in the 12's .

 

Intercoolers don't determine AFR. Read more, post less.

 

I read just as much as I write, forgive me for not knowing and understanding everything, this is my first Turboed car and I'm on here looking for help not an opinion on my intelligence, but I forgive your rude behaviour.

What I've come up with is the intercooler runs hot once it reaches its maximum cooling efficiency, which isn't much higher than stock boost, that causes detonation, it runs hot around 10+ pounds boost on stock Turbo causing very hot iats 140-170+

 

that is because there isn't one set answer. it depends on fuel quality, altitude, AFR, timing, engine health, etc etc.

the safest way is to start at the lowest boost you can, tune it, then raise it, 1-2psi, tune it there, and then keep going until you're happy with the power, out of injector, or you can't control the temps anymore.

safety comes with testing YOUR actual car. we do have some nice guide lines to start from, which is really nice.

if you think the top mount is too weak, then change it. or you can put some temp sensors in there and actually test it....

 

 

running 1.1 bar trough the top mount, IAT's come around 70-80 degC when pushing. running quite a bit of water/meth before the compressor to keep it alive

anyone noticed the really sharp edge where the tube that goes trough the throttle body 90 deg hose is merged to the intercooler. I was thinking to smooth it out, but then how to remove all the aluminum chips out of the core?

 

There's a thread on here where a guy modified the stock top-mount to flow better. I almost bought one off of him, but I'm a broke FC owner (EX FC owner now...)

 

I got it between 0.5 and 0.7 bar, streetport, bnr stage 4. Mine runs up to 50 - 60 ēC. This was also the reason not to continue with mapping. Can't wait till i can start at my v-mount setup

 

My friend, I would get a wide band O2 and get the car running well with a good tune using the stock waste gate pressure first. Running the stock compressor, it might run out of steam and start producing heat at a certain point. Maybe some one else can chime in on when that point is.

 

I'm planning on 10 psi for mine, I'd like to run 11-12 if itd be safe

Rotary > Pistons

 

When I had a stock top mount inter cooler on my FC, my tuner didn't tune past 11psi because of how quickly the intake temps would rise.