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Sexy shroud mounted rad; viewtopic.php?f=37&t=130150

I've been through his build. This guy is a monster. I cant even imagine being able to create something like that. I'm down to either using a way overbuilt radiator in the back, or just come to terms with having to plumb a front mounted one.

had you ever considered using multiple motorcycle radiators?

Why are set against the front mounted radiator? Mine is barely noticeable and cools great. I could have made even less obvious but chose not to.

this is what we run in our ecotec baja never a problem, we are relying on the fan entirely and the trapped air is removed with the overflow tank. Have plans to weld a neck on the fill and eliminate any air pockets. but never runs hot

I have been driving around in my 70 bug (not baja) rear mounted radiator. After two years of trials and errors, I have decided that I am going to move my radiator to the front.

I live in southern california where it is warm weather and lots of traffic. My bug is my daily driver. I am running with a stock ej22 with the original stock subaru radiator and fans. I tried running with scoops underneath the car, separating the radiator from the motor, added decklid stand-offs, and even added side scoops. The coolest I had it usually running was at 190. I only had a couple times that it got too hot that I had to pull over to let it cool down. My radiator would turn one fan on at 180 and the second at 190, so my fans were always running. It also didn't take long for the motor to heat up to 190 too.

There are many problems with the rear mounted radiators.
1) Heat soak is the main problem. Having the Radiator in the same area as the motor causes major heat soak and the air intake is constantly just pulling hot air in.
2) It is hard to have a unrestricted pathway for the heat to escape. I even added a wing to the bottom of the car, to try to help pull the hot air down and out the car, but it didn't help.
3)With the motor and the radiator in the same area, it causes a lot of heat. Being the starter is in the same area, I had many times that starter would get so warm that it wouldn't start unless it was a cold start. It didn't help that I also had my rad fans pushing hot air onto it!

My next step would be to buy an aftermarket radiator and fan which I know it will greatly help. But, if I am going to buy a new Rad and fan, I am going to buy one that will fit in the front. I know there are ways of getting a rad to work in the rear, but I just don't have the time and money anymore for more trails and errors.

Have you ever tried just running the fans reverse of what your last picture shows?

If not, it might be worth a try to block off the side scoops and give it a shot just to see if there is any difference.

My guess is that there is a bit of a low pressure area at the back of the car and you are fighting that when in motion, and just sucking hot engine air when stationary.

Like many others also i tried to get a rear rad working.
I think the issue of warm air re-circulation is almost insurmountable in the back of a bug.
You have limited clean air flow through the rear vents pushing against rising warm air through the rad straight into turbulence coming up from below.
The only solution I saw was having a rad above the engine and completely sealed, much like the aircooled tinware, creating a hot/cool zone.
Looking at my Porsche Boxster they could have engineered rear rad's but went with the much more complicated multi front rad system with a mass of pipework and joins.
In fact one of the rear inlet vents has a fan to remove the residual engine heat that builds up in traffic.

https://www.youtube.com/watch?v=D8_hQr-JKUM

rear rad