Radiator Placement

[Steve C]

Hi

The best place for air flow is in the front, a guy on another forum (look for use name Baja Wes on http://forums.aussieveedubbers.com) I visit fitted a V6 Mazda motor to a Baja with the radiator above the trans, he has over heating issues at higher highway speeds.

On my old 1302 I ran 1.5 inch stainless tubes to the front of the car, they followed the chassis bolts under the pan, my car was pretty low and I never had an issue with them hitting the road.

Steve

[ricola]

These are my main and chargecooler radiators.

Unless you have a seriously good reason or a very small engine I woldn't even consider a rear mount radiator. There is NO substitute for natural air flow.

Rich

[Steve C]

Hi

Also having the radiator & cooling fan at the front moves some weight forward, no a bad thing.

Steve

[beetle1303]

I ve seen some watercooled beetles with their rads up front, in real life and many owners are unhappy because his car is running a bit hot or even overheating. This may sound funny but its not only the natural air flow and cold air that is needed. Fitting the rad in front and closing it inside a box is part of the equasion, but remeber that you must provide the rad with enough back spacing in order to allow the hot air to escape ( something many times overlooked). If you make a box big enough just for the rad, trying to lose the less possible space, you will dissrupt the air flow and the rad will not work...

the best thing that comes to my mind would be a rad tilted backwards (top towards the back) with a cover that would be tilted forward. Also try to make a tunnel at the rad entrance going up to the body work. This would improve air velocity and air path thus improving the air flow to the rad. Race cars use a tunnel with a smaller area entrance and gradually the tunnel gets bigger until it reaches the rad. Next you should find a good place for the back tunnel outlet. The best ive seen was a 1303 with vents on its bonnet like a lotus elise/exige.

I would like the Idea of to smaller rads, one on each fender well but with the addition of either louvres or something like that to decrease lift

Sorry for the long reply

Chris

[Panelfantastic]

Rad needs to be up front. I've wasted a lot of time and money tring to get the rear rad to cool. Don't be me.


Jeff-

[Jeza]

You also loose some heat from the pipes if they run under the car, which can aid cooling.

Like Chris says airflow out is often over looked. This is really important, if air can't get out then it ain't going to go in!

[Steve C]

Hi

1303 you bring up some good points. The hot air that has done its work is larger in volume so its needs an easy path to escape.

On my 1302 I only had the stock grilles in the front apron AC front apron and the spent air went over my frame head and onto the road. It gets pretty hot in Sydney during summer (25-40 Celsius) and I never had any issues, the cooling fan only came on after standing in traffic and at around 50 - 60 kph the forward motion was enough to keep enough airflow through the radiator to keep the motor cool.

One mistake I did make was trying to keep the motor to cool with an adjustable fan switch, once I assigned the switching duties to my ECU it all worked great.

I’m not sure what sort bug your building Bugscandrift, perhaps you can let us know so we can offer better advise.

Steve

[volkdent]

In my head I always think of gathering the air into the radiator with ducting, so whatever air is trapped by the ducting HAS TO go through the radiator. Then on the back side, provide a nice open area or vacuum to carry the hot air away. I just ordered my radiator today, 8" tall, 29" wide. I'm hoping that with good ducting and 3 8" fans pulling from behind that it'll be enough.

The proof is in the pudding, so really, ask this guy Zenjoes Rotary Bug to see what worked for him and many like him using the rotary motor. There is also VolksSwap, a related site.

Jason

[Mikey]

For what it's worth. I'm going with a Suby conversion in my Ghia. I'm going with a front mounted radiator. I'm thinking the Ghia will accept it a little better than the bug. I'll make the hole in the body for the horns bigger and route the air from the front grills to the rad. Should be plenty of air. And I know I'll find enough ways to get it out too.

I even had an idea of small air deflecters behind the beam to help deflect the air towards the bottom of the car.

Just my 2cent.

[Racelook]

Originally Posted by ricola

I woldn't even consider a rear mount radiator. There is NO substitute for natural air flow.

Rich

Hey Rich

Than first look at this
http://home.tiscali.nl/~gmolhoek/alf...ator/index.htm

With some minor ducting (that is hidden under the car) there is enough.

Wiebrand

p.s. I probably never will put an radiator/oilcooler/intercooler at front.

[ricola]

All very nice in a car with no rear end. I'm sure Wes would agree that it is quite a simplified model and will help him improve his Baja cooling (which has problems at speed currently). It also doesn't have a radiator in there which would also reduce air flow.
But, that site is for a 1350cc Alfa engine which requires very little cooling in a relatively cool climate. Also remember that the width of duct would be very small with an IRS rear end and you have the hot gearbox right in the middle so I don't think the flow would be that great in reality. You still need to get cool air around the engine for extra cooling and intake.
When I had the Alfa engine and rear mounted radiators in the speedster I was looking into and experimenting with scoops, it was borderline in the end and relied too much on fans.

Rich

Originally Posted by Racelook

Hey Rich

Than first look at this
http://home.tiscali.nl/~gmolhoek/alf...ator/index.htm

With some minor ducting (that is hidden under the car) there is enough.

Wiebrand

p.s. I probably never will put an radiator/oilcooler/intercooler at front.

[Racelook]

Your right about that Rich.

Wiebrand

[Rob]

Originally Posted by Steve C

On my old 1302 I ran 1.5 inch stainless tubes to the front of the car, they followed the chassis bolts under the pan, my car was pretty low and I never had an issue with them hitting the road.

Steve, how did you mount the tubes ? Did you bend them to follow the lines ?
Got any pictures of that setup ?

Thanks,

Rob.

[Steve C]

Hi

These are some photos from under my old bug, my old camera was a bit dodgy. I mounted them from brackets on the heater channels bolts. They were bent to follow the line of the chassis bolt U section.

Steve

[volkdent]

Steve, what material did you use for your tubing? I'm looking at aluminum, I figure it's lightweight and the same material as the radiator, but copper would be better at heat disapation(sp?) I was thinking.