Has anyone ever thought of doing a rear mounted radiator? Like at the back of the trunk area with a NACA style duct in the top of the trunk lid to funnel air to it? Just a crazy idea I had. Can anyone share why it may not work or be feasible?

 

Umm, where yea gonna put it? Lay it in the trunk? Put it on the wing? I dont think is would work on an evo. Maybe a Peugeot.

 

the piping would be so long, you may loose alot of efficiency maybe

 

The length of the piping would aid in the cooling. Would have some pumping losses/pressure drop though from the water pump. . .

As for mounting - it would be vertical at the back of the trunk with a hole cut in the rear of the trunk lid for the air to flow through. . . may decrease drag too . . dunno

 

lol this is just crazy town

would the benefit even be worth the work and fabrication?

 

to do this you need two pumps, a forward pump and a return pump. Also you don't need ducts to push the air through. All you will need is one high velocity push fans. The rear of the car is a high draft area so it will draft the heat out.

 

Are you trying to aid/shift weight balance?

I would think you start getting into the same issue as the mini battery where the piping gets so long you are adding more weight than it is really worth. Think weight of tubing + fluid for 20+ feet (output from engine & return).

OTOH you probably have a 20-30lb lump hanging off the very front of the car that would be nice to move.

Another thing that the C6 Corvette race team (Pratt & Miller?) did was move the alternator to the rear of the car and it was driven by the rear axle. It was mounted very low too. Badass.

John

 

Stephan Verdier's drift car uses this type of setup. I was working a tire progam with him a couple weeks ago and was telling him about my overheating issues. He told me that when they made the change on his drift car it instantly fixed thier overheating issues. A drift car spends more time sideways than straight-on, so this type of setup makes intuitive sense to me on a drift car. Not sure how well it'd work on a rally or track car. FWIW, you will probably want to feed through giant NACA ducts where the windows or doors are with 10-15" tubes. I thnk it's ducted out the bottom of the car but haven't been able to find any better pics.



I'm not sold on the idea, but have been considering it fairly seriously. My other thought is to go with side-by-side IC & radiator, like the last Mitsu WRC car used, pics can be seen in this thread:

https://www.evolutionm.net/forums/ev...ngine-bay.html

Dave

 

Thanks for that link. On there I found this!



Check out the nice dual radiator fans in the trunk!

 

So what's the primary reason driving your interest in this?

Dave

 

To be truthful - no reason at all. Just a random idea that popped into my head and wanted to get some input.

Benefits I can think of:
- better weight balance
- less drag (infuses air into the turbulent wake area directly behind the trunk and allows air normally trapped in the cabin to exit)
- possibly better cooling
- would look pretty sick

 

So I am in the process right now of building a rear-cooled car. It is going in a Datsun 510 being built for a special alternative fuel class. The idea is to put as much weight in the back without moving the transmission rearward. My inlet will be a small roof scoop and the exit will be on top of the rear diffuser to blow off some draft from the flat back of the 510. I will be using 2 large water pumps and sending the piping down the length of the car with aluminum pipes inside vented tunnels to add some intercooling.

There are many reasons for moving the cooling system rearward. First of all there is a new trend in performance vehicles that is to move as much weight over the rear axle as possible. Secondly, due to decent intercooling, you can use a much smaller radiator as long as you can move as much water as needed to continually get cold water to the engine and back quickly.

Photos:

 

Gotcha. I'm still up in the air over whether to euro-rallycross the Evo. I'd love to do it, but would need to find a bodyshop that'll sponsor me. LOL In that series, seems lots of cars are built that way so its got to work reasonably well, and euro rallycross cars make even more power than WRC cars.

Dave

 

Dave,

What is Euro rally cross? Is that head to head or mirror image courses or something like that?

BTW - working with DHP to build a completely new wing setup for the car. Stay tuned - if it works out as well on the car as it did in my little mind it should be killer. Taking some ideas from the HKS TRB-02 car mixed with my own thoughts. Should work out to less than 1/3 the weight of my current trunk mounted wing setup. . .

 

Matt -

That build looks pretty serious. I thought about the intercooling effect of running such long tubes. Kinda like the STS rear mounted turbo kits that don't need an intercooler because the IC piping is 16 feet long! Now if only someone had an aluminum tubing extrusion that was finned for more surface area to act as an even better heat sink.

Something like this. . .