The arrows pointing away from the car are low pressure. Those pointing towards the car are high pressure. The inlet is in a low pressure region. This is a good example of why you don't want an intake in this location. However an intercooler/aftercooler,heat exchanger,etc does not care about air pressure. It cares about air flow. There is significant airflow at this location.

Modifying the ducting through the hood to make the path for the air smooth would help. Making sure that the hood completely seals against the intercooler also helps. However you need to do 2 other things. One is that you need to find a way to get rid of the air after it passes through the intercooler. This is what removing the heat shield helps with. However it compromises problem two which is that you don't want radiated heat warming up your cooler. Without the heat shield this isn't really an issue while you are moving. You have airflow which keeps heat away. When you are stopped though is when the most heat buildup is. It takes a little while to recover from heat soak and you feel this when trying to accelerate. By the time you are up to speed the heat is removed but you also aren't on the gas very hard anymore so you can't really tell. All you know is that you felt slower. For road course track events I never had a problem with a top mount. I wasn't pushing mega horsepower either but it is effective at doing it's job. I did later have a large front mount which did cool better.

As I've said before, there are pros and cons to every setup and I can argue both sides. Don't discount a top mount as inferior just because it's a top mount. There's more to it than that and it's not always a bad thing. Top mounts can be very nice.

 

Do you think the airflow in the hood scoop could be improved? it seems like there are tons of holes and places for the air to to through rather than hitting the aftercooler. What do you think about improving this slightly, and also improving the plastic inlet piece for the scoop?

 

Actually the same size - I had to measure it when they both came back, as it does look smaller.

 

Excellent post by rotarygod, as always

 

That's really what I was getting at. The airflow through the scoop isn't smooth. This doesn't help things. It could be improved if someone wanted to get a little creative and it wouldn't have to mean cutting the hood apart. I don't have a TII anymore so I can't just go outside and figure this out for myself. I do remember what it looked like though. The factory hood has a rubber strip that seats up against the intercooler when the hood is closed. They are trying to keep all of the air directed at the fins rather than going around. It's the underside of the hood itself through the duct that is the biggest issue.

 

I cut some thin aluminum to help block off the open spots on either side of the inside of the scoop but didnt notice much difference in temps. I am going to try to improve it a little by attaching teh ducting to the scoop insert, maybe put some foam around it to help seal it from inside the hood

 

How much clearance between the IC and the engine is there for the air to escape after it's gone through the core?

 

...

 

so why not just cut some vents into the hood at the front, mount a naca duct there, then rout some cheap hoses to blow air under, and around the IC so that when moving, the air hits it and cools it off.

Also, i was thinking, why not just take this example, and just mount some vents in this area. I know when moving it wont help much and might cause some airflow problems, but if designed correctly (build a box so that most of the heat from the turbo escapes through through the hood) and put some vents right where the aftercooler is? just to let some of the hot air escape allot faster.


Or just screw it, why not make an aftercooler water sprayer?

 

Well i certainly am impressed with the response and discussion over the top mount versus front mount intercooler, i appreciate everyones input. It is very interesting reading, although i am undecided as what to do. An fmic seems the most effective way if you are going to run higher boost and i guess gives more scope for future mods, but i really don't want to drill holes in the engine bay to fit the piping. Has anyone done one without doing this?
Living in Queensland Australia where summer sees regular 30+ degrees celcius daily, the heat soak problem is certainly a factor.
I was considering setting up a water spray system and wanted to know if anyone has successfully done one? Would you be able to give me some starting tips?

 

http://www.1300cc.com/howto/how2/front.htm

 

One of my concerns about front mounts is cooling air to the radiator. I know that air flows right through a front mount and still gets to the radiator. That's not up for question but it still does block some airflow. The problem is that it picks up heat from the intercooler and this hotter air is what is trying to pull heat away from the radiator. Admittedly it's probably not much of an issue as most of the time you aren't under boost which would mean you aren't picking up much heat either.

In the long run it's probably just cheaper to do a front mount unless of course you want to fab up your own top mount. The ARC unit looks pretty nice but it's just too expensive.

 

Maybe for a street or drag car. On a track the only time there's going to be no boost is when you're on the brakes.

 

thanks Trots that is a good write up. definitely food for thought, i appreciate it mate.
cheers

 

That's true. Fortunately 99.99% of the population doesn't ever see a track.

 

I'd say unfortunately, since it makes you a better driver. It's appalling how bad the drivers out there are nowadays.

 

I agree with that entirely. I do see lots of people that think they are race drivers though!

 

this might be a little off topic and stealling this thread, im sorry if i am

but my friend just bought this for his 88 turbo 2 that we're building
and i wanted to kno if anyone knew wat brand it is cus it really doesnt say nuttin only thing i see is toyo radiators

 

looks like a Side mount IC from a Nissan car SR, RB CA

 

it mounts nicly as top mount though

 

nice one,

just a quick question though. by removing the lower gaurd. dont you expose the engine electrical harness and solenoids to a higher heat issue which could lead to failure??

some thoughts ive had

i was looking at it the other day on my engine (i have the arc cooler, just havent installed it yet).

if i used the original top gaurd to fit a custom cooler made with the bigger inlet/outlet that was longer (front to back, with under gaurd modded to suit different cooler size) and keep the same thickness core and run a remodeled lower guard (i have access to sheet work tools). could it be possible to have the best of both worlds..

i also have access to heat resistent materials as well to put a "blanket" under the sheild to try and avoid heat soak.

ie better flow in the core and through the core and a decent "exhaust" for the core??

as i have always thought part of the issues with the intercooler was the lower gaurd due to its actual outlet size compared to the overall core size..



thoughts?

 

Looks like a HK$ FC upgrade top mount.Core fins are pretty beat up.Go at it with a small pair of needle nose pliers for 5 or so hours and you should be good to go

 

i was thinking goin wit a thin dipstick to start it off the get it better wit needle noise

 

you thinking heat transferring, not heat soak. the inter cooler is placed in a naturally hot spot.

like i have stated, just block off the turbo and vent the hood, and you should see a noticible decrease in the speed in which it gets hot

 

well i bit the bullet so to speak

here -

the intercooler is going water to air. this is the style im going -

read here - http://www.ausrotary.com/viewtopic.php?f=4&t=164573

how im doing mine -

cause of the backpressure the original core will give to my t04e turbo. cause after 12psi not much gains are had. (been shown there is only a 5hp gain from 12psi to 14psi on another forum on the stock cooler)

now since im capping at 14psi id like to to be better flowing.

my issue is i want a good intercooler but dont want it to look like a water to air system as i want it to look like factory cause of the rarity of the vehicle..

so looking at using this system and mounting 4 of them water cores in a row and run the cooler the same configuration as the factory cooler.

ie air for motor runs from front of cooler (front of car) to back of cooler (back of car)

water cores run east to west.

then mount it so its slightly lower than the factory unit (cause all up it will be about 50mm thick so should be room)

then saw the top face section off the original intercooler off itself and also take off the original gaurd. then tac weld them to the top plate of the new water to air cooler to give it the "factory look".

water pipes run under the top guard so unless ya looking for them you wont notice and run a custom radiator for the intercooler at the front of the car painted black..


id like to run an ecu water temp sensor in the exhaust side of the water jacket of the cooler.

run the sensor through the haltech e8 ive got and get it to run 2 outputs..

output 1 - set at a temp so when it starts to heat up it will start circuilating water with electric water pump

output 2 - set to a higher temp so that when it gets hotter it will turn the thermo fan relay on

this should eliminate alot of heat soak too i would hope..

thoughts?


ps anyone want to buy an arc top mount intercooler?? lol