psyber_0ptix

iTrader: (4)

If the condenser is in the trunk, where does the rear mounted turbo go?

patsmx5

iTrader: (16)

I don't know what your talking about...

bbundy

My intercooler basically sits sealed to the bottom joggle in the factory mouth piece duct. there is about a 3" gap between the intercooler and the factory chassis crash bar for air to flow up and over the top of it into the area sealed to the radiator. I run one fan and an oil cooler sitting slanted between the bottom of the radiator and the steering rack is fed air from hose ducts run from holes in the lip spoiler. It may not be a perfect setup but it seems to be effective.

You need ambient air flow through the intercooler which requires a pressure differential it wont work for **** if you just stick it in a plenum area without forcing flow through it.

Savington

iTrader: (31)

What they're accomplishing is zero radiator airflow and the most efficient way to overheat an internal combustion engine ever devised by man.

Yep. I tried this, I've never had a car overheat so fast.



This setup let my 350whp track car run 20min sessions at <215*F in 105*F heat. IATs were ~30*F above ambient. There are two sealed chambers behind the IC, one ducted to the top of the rad (fed by the upper mouth duct) and one ducted to the bottom of the rad (fed by the lower mouth duct). I suspect I could have dropped IATs a bit more by venting the IC under the radiator.



The gap is critical. I'm starting to see IC setups that are sealed to the crash bar, and once you do that, nothing will prevent overheating.

You understimate the ability of 100mph worth of airflow blowing directly onto the face of a heat exchanger to create a pressure differential without too much regard to what's sitting behind/above/around that heat exchanger.

nitrodann

having a fair bit of experience 'fixing' track car cooling systems for people, I wholeheartedly agree with Sav.

18psi

iTrader: (76)

agreed for the most part.
the 1st bolded part is simply not true, since many of us have found 1 specific brand from ebay that actually has properly placed and spaced turbulators.
the 2nd bolded part is a very bold statement, I can't wait to see if it holds true (because I can think of at least 2 sizes currently available that are, IMHO)

Braineack

iTrader: (62)

this one was quite large.



His AIT's would never break ambient on a 1/4 mile track.


why do you care about such a large core? building a drift car?

18psi

iTrader: (76)

he's building a highway pullz bro car

2jz and nas

Braineack

iTrader: (62)

putting together a 2jz miata, can't use measuring tape.

Shortpersonbk

I want a good starting spot so i can purchase a core and cut things to make it fit.

In classic turbo miata fashion a simple question had a couple helpful answers..and then went down hill from there . Back to googling to find info vs asking for helpful advice from people with experience on that subject.

patsmx5

iTrader: (16)

In all fairness, there's probably 10 good post in this thread already. Maybe only 2 or 3 answer the exact question you asked, but still it's a 9/10 compared to what it could have been here. Better still, most of those extra post that were useful were people who go fast with real world experience posting their experience, not BS.

Shortpersonbk

I agree there was some helpful post, enough that it helped me decide which core i am going to purchase and try out.

Yours were included in the helpful post of course. I am going to buy a treadstone of similar size to yours.

Corky Bell

Selecting a core size has several considerations.
Cooling air to the rad.
length of tubes
thickness of core
end tank shapes
internal flow area

Tube length: 12" is about 80% efficient, 22" approaches 92/93%, 25" is excess dead weight.
Thickness: The thicker it gets the lower the efficiency. The back half of the core gets nothing but hot air. Suggest 3.5 to 4.0 is about optimum.

Tank shapes are very important for low flow losses. Streamline, streamline, streamline..

Internal flow area controls (in major part) the flow loss. Look at Bellintercoolers.com for some guide lines.

Longer tubes have more drag, keep in mind

In my experience, keep the core thickness under 4.0, tubes over 18" and flow area to match BIC suggestions.

Almost everything else become dead weight

Consider that an 18" tube can offer about 90+ thermal efficiency, then what would a core do that is twice as long? maybe 6% better, twice the cost, more drag and heavy.

Keep it within reason. There are many good cores available, but not all are created equal. Quite hard to easily distinguish. Density of turbulators is one tip. The more the better.

Corky