mr2daj

iTrader: (-1)

is it normal to duct the intercooler along with the rad? my race car feels quick for the first few laps then power dies off a bit. i am putting that down to intercooler heat soak. the intercooler is in front of the rad but is smaller so the air can just escape around it and not go through it. is it normal to duct separate?

hustler

iTrader: (6)

yes, do it.

GT42R

I think proper ducting is one of the most overlooked aspects of any turbo build. Look how much emphasis OEM's put into cooling system ducting.

mr2daj

iTrader: (-1)

i have good ducting to the rad but the intercooler is just in front of it. i need to come up with a way to give it its own flow. anyone have any ideas? its a large squareish cooler. i am thinking maybe a separate vent/duct above the mouth. thought about intercooler spray controlled by the ecu too.

hustler

iTrader: (6)

Mine is set up the same way and not ducted. How big is your intercooler?

mr2daj

iTrader: (-1)

the intercooler is pretty big 550x300x80mm. surley the way we have it will not be very efficient as there is no low pressure behind it. just high pressure infront of the rad and the air will just take the path of least resistance and go around the intercooler.

matthewdesigns

iTrader: (8)

I've got mine ducted from the bumper mouth to the radiator, with a relatively large IC core hung in the airflow path, no separate ducting. I did make an allowance for the height of the IC core, and dropped the ducting below it about 1.5" so that enough air can get to the radiator. I don't overheat, and the outlet side of my IC is always cool to the touch even after beating the **** out of it.

mr2daj

iTrader: (-1)

How about getting the intercooler really close to the radiator and sealing between with foam? This way the intercooler will have low pressure behind from the back of the radiator and high pressure in front. I am not sure just having it in the airflow infront of the radiator is good enough. It's like the difference between ducting your radiator and not. We all know the rad needs to be ducted so the intercooler should get the same treatment. the colder the better.

matthewdesigns

iTrader: (8)

As long as you are ducting up to the front of the IC core and essentially sealing it there, that could probably work for a street car if your core is not terribly thick. If it's a race car and you are in boost a lot, then you are going to be doing nothing but providing the radiator with hot air. However, I really don't think it's necessary to stack them together and seal them essentially as a unit, and you may even be going backwards a bit since the radiator won't be getting any virgin air, and while your issue now may be poor charge cooling you could create a situation where your coolant temps are higher. I've ducted a bunch of high HP turbo cars the same way I did my Miata and they've gone from overheating at idle with AC on to running nice and cool at WOT with the AC cranked. I've even introduced fresh air between the IC and radiator cores by way of dedicated ducts (increasing pressure between them) with excellent results.

In addition, not ducting ahead of the IC/rad combo will only cause you more issues with your idea, as you are adding that much more of a blockage to the air trying to get through them. Also, make sure you have an undertray behind the radiator core as this helps to generate the negative pressure area there.

triple88a

iTrader: (2)

Getting air to the unit is half the battle, getting it out will help quite a bit.

V mount is a your answer however hard to implement on stock chassis.

mr2daj

iTrader: (-1)

what i have ended up doing is fitting the intercooler up against the rad with foam between. the rad is all ducted so now air has to go through both. this should bring charge temps down a lot and as has been said may increase coolant temps but we will see in testing how it goes. i am also doing to open up the bumper mouth a bit to get some more air in there and have moved the oil cooler which was in front of the intercooler. we have a pretty good extraction hood to remove air and the car already had a large front splitter running back to the sump but we are currently working on a full flat floor and rear diffuser.

just as a bit of background this is the only turbo mx5 (miata) race car here in the UK. i know a lot can be learned from u guys who have been doing this for a while now. we learned a lot last season and big changes are being made to correct issues that we had.

EunosBen

Anyone upload pics of what you have done? Pictures say 1000 words!

mr2daj

iTrader: (-1)

does not really show a lot of detail. no ducting fitted here but intercooler sealed up against rad.

Handy Man

The amount of flow can be determined by the pressure differential across a heat exchanger. The pressure in front of the intercooler & radiator (assuming they are stacked) will be essentially the same. The pressure behind the radiator is low (or at least it should be). Without the back of the intercooler sealed to the radiator, the pressure behind the intercooler is essentially the same as in front, therefore not getting much flow. With the back of the intercooler sealed to the front of the radiator, the intercooler will see much more flow (the same amount of flow as that section of radiator), but that section of radiator will also have a higher inlet temp.

Of course, ducting the whole system is crucial to achieve high pressures in front

mr2daj

iTrader: (-1)

thats what i was trying to say earlier. cheers for confirming what i thought.