Aero and Intercooler question mid engined car

[AfterNvy]

Hello guys,
I found lots of topics on here with a rly nice thoughts and wanted to share an idea with you for my car build so I can get your feedback.

Car:
Toyota Mr2 spyder/roadster depending on where you live.
Engine - 1zz-fe - 140 hp stock.
Power goals - 230 hp at the crank, but would be great if the cooling system can take more.
Turbo - Garrett 2554r

So it all started as a stock car but what I wanted it to be is a track toy. Initially I wanted to improve the aero and after lots of research thats in the works now.

What problem I need to solve now is how to design my turbo kit and where to place the intercooler.

After the initial research I came to the conclusion that water to air cooling will be best for the mid engined layout but couple of things are putting me off:

1. Weight. The car weights less than a ton and I would like to keep it that way. Nicely designed system can weight 30+ kilos.
2. Complexity. The w2a adds lots of complexity and couple of more points of failure and I would ideally like to avoid that. Pump, plumbing, tank, heat exchangers.
3. More load on the electric system.

After that I started researching for some places to mount the air to air intercooler but thats really hard with this layout coz it has to be behind the engine.

Couple of ideas:
1. Above the exhaust in Porsche 992 style, id have to create some ducts to direct some air to it tho. I thought that the ducts can be in the rear wings and to route them somehow to the intercooler. I have no idea how to design them so i dont screw the aero of the rear of the car.
2. Below the exhaust angled. Pretty much angled like a diffuser would be. 2 ducts from behind the wheels, ill cut the lining and will route the air on the intercooler.
3. Behind the rear wheel. 1 duct from 1 of the wheels, the intercooler cant be huge so it will not be ideal.

In all of the above cases the vacuum from the car moving would help the air to be drawn out so ill not rely only on intake ducts. Also the intercooler will be shielded from the engine so it doesnt heat soak.

Any input on the whole design and the ducts would be appreciated. You can easily find the car on google for some pics and inspiration.

Thanks

 

[MintJulep]

What model year?

 

[MintJulep]

I guess regardless I'd be thinking in the rear"boot" with NACA intakes on the sides and discharge out the rear.

 

[AfterNvy]

The car is 2000 year so it doesnt have a rear boot, its a small cabrio. There is some space between the strut towers and the crash bar for some intercooler placement and yeah the exit will be from the rear where the number plate is. Ill relocate it for sure so i have bigger surface.

Can you give some more details how to design the NACA intakes? If you mean like the ones of the 2nd generation Mr2 95-99, I cant have such ducts.

 

[GregLocock]

Typical track usage is 60% of the time you are at full throttle. Do you think Toyota will have built the cooling system to cope with 60% full throttle*160% rated power? No, neither do I.

So rather than Mickey Mousing extra heat exchangers you probably need to look at redesigning the main radiator as well. While you are doing that site your intercooler as well. Of course the easiest thing to do is to copy somebody else's solution.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[Comcokid]

Here in the US, the Acura Integra (Honda for those not in the US) with the B18 engine it is popular to add a turbo and other horsepower improvements. For the intercooler what is frequently done is to upgrade the engine radiator to a three-row welded aluminum that is half the size but a little thicker. The engine cooling of more efficiency/area keeps things about the same at half the size. An intercooler is then installed in the now available radiator space.

I can't comment more than that. My 92 Integra GS has an automatic transmission (not popular in the racing crowd). Nevertheless, I installed a full-size welded aluminum racing radiator years ago modified with the stock transmission cooler in the bottom. To me "High Performance" means I can run the A/C at high and be cool in a traffic jam in the middle of a hot summer.

 

[gruntguru]

You can easily hit your HP goal without an intercooler or larger radiator. Water/meth injection will do some intercooling as well as reduce heat load slightly and help with detonation. This combo and premium fuel will easily handle the 10 psi you need for the 60% power increase - with standard pistons and compression ratio.

If you can run E85 fuel, 100% power increase or more is possible - still with stock internals.

je suis charlie