Looking to do a rear mount radiator set up
Got a few questions, how big the pipes should I run to the back ?
If u have done rear rad set up
Can u please share ur pics
Thanks

 

 

Pipes are alloy 1 1/4 inch and run in the tunnel and come up at the firewall.
Tried running without a thermostat but it wouod not get over 65 deg. The system works very very well.

i did not do it for **** factor, It was the only place to fit the radiator as there is no rook in the engine bay

 

http://www.oke020.com/

Look at the bottom of the page start at the last number and work your way to #1. Build log that shows a rear-mounted radiator (in there somewhere pgs 24/25)

 

that is awesome dai-18t

http://www.motoiq.com/magazine_artic...ubaru-sti.aspx

 

Took ages to get it all sorted and working properly considering it does twenty lap stints.

The main thing is to have good air supply, but that air feed on the WRX is way overkill. The two Six inch ducts and scoops on mine were way more than enough. You need carefull planning with rear rad setups.

At first i was running just the rear quarter dual NACA ducts with 3 inch pipes(4 all up feeding the rad) with the alloy scoops on the NACA's. It would still overheat. It turned out the 3 inch piping was too much of a restriction. Here are some pics...







That led me to the twin six inch duct design I posted earlier but with out the scoops in the picture. In that state the car would never get over 65 deg C so i had to fit a thermostat.

Personally I believe that my rad size is too big(the core fits two 16 inch spal fans). I would say one haf the size would have been sufficent considering the radiator is away from any engine bay heat soak. I just went as big as possible to be safe.