I know this had been tried 7+ years ago, I was wondering if since then has anyone done a watercooled conversion and not put the radiator in the front trunk?

Robert (rotary914) has. However, there is lots of free area with that tiny engine.

Master Mueller's "engineering mind" is back hard at it just as he never left. Wonder what creations are being planned????? Hope he never talks to the great Doc Evil and others; it will cost me money since I probably will want to build it.

Steve Hurt

Straying from the promise to the wife "I'll keep this one stock!"



Just seeing what people smarter than me have come up with...not too difficult to achieve that!

My 2.5 suby turbo goes up to get the final brackets and radiator made next week.
We will see what he says, but, with the shelf out, it looks like enough room for a dual core wide radiator with 4x12 inch fans. I am concerned as California gets a bit warm.
I will let you know!

jeep cherokee rad is like 10 x 36 and they make all AL versions.. shelf out , three fans mounted low I bet would work... but then again Bigkat shakes his head a lot at my ideas.....

I always thought that using two small radiators in some IMSA. Style rear fender flares would be nice on a V8 conversion. Not subtle, but should have enough cooling capacity. I always liked the look of that Altec Lansing racer.

I would love for the radiator to work in the engine compartment but logic says no. Heat from engine and little airflow work against it. Do you know of any production mid or rear engine car that makes it work- I dont. Again, I'm on your side. If I didn't feel it absolutely neccesary to mount the oil cooler on my gt build or the rad on my suby build up front, I wouldn't.

^^ Countach and Diablo.

GT engine lid and some scoops to increase airflow when you are moving. Fan tech has gotten a lot better this past decade. Spal 14" fans to 1840cfm. Max to fit under the lid 16" fan 2024 or 2467cfm ($$$).

Can't find my notes but iirc mine's about 2600cfm for both and my break even point is around 30mph.

Run an all aluminum engine... they dissipate heat better and they need to run hotter than old iron.

Uh huh, that's the theory....

So, running an air cooled big 6 gets enough air. Why wouldn't a large 4 get enough with fans?
Inquiring minds want to know.

It's also been done with an N/A Scooby motor. There are photos around here somewhere. Not sure what happened after the first few months with it, though.

--DD

Exactly, water is a more efficient medium than air so if that compartment can shed 300hp worth of an air cooled* 3.6 it seems that same space can shed the heat from a 300hp 4 or 6 water cooled motor

*anyone have the numbers how much cooling is really done by the oil?

I always though a rear spoiler with a radiator enclosed would be the way to go but

I think the way a boxster does the dual radiator s in the front corners of the bumper is

Brilliant

And I would never hack up my front truck for water cooling , just stupid

Mike, don't do it.
Keep it aircooled and drive it a lot sooner.

https://www.google.ca/search?q=f1+chassis&a...f-e%3B960%3B465

https://www.google.ca/search?q=f1+mid+mount...F%3B1680%3B1260

A new way to slice bread.

Thermal conductivity of oil and water are known constants.
Squirting oil to the bottom of pistons and tops of cylinder heads are effective methods.
Air and oil cooled,a lot of oil,a lot of surface area.

Click to view attachment
Do we have to put the rads up front?
Making them fit in the middle down low will require some different approaches.

Moving a lot of air for the aircooled.
Adding exchangers to cool the extra volume of oil with the associated weight.
Being able to dissipate the heat of a high compression n/a or turbo engine reliably is it.
50 % efficiency of a 200hp engine means cooling 200hp of heat.

Interesting side rad setup... would you have that much room on the sides and still keep all the rear trunk area? Maybe the rads would have some ducting to direct the airflow and you could run them flatter in the compartment to save room? I'm going with the upfront design but laying down at an angle but I'll definitely look into this setup for a turbo intercooler and oil cooler solution.

Click to view attachment

Step to the left.
Step to the right.

Click to view attachment

Not the first.

it's easy to cool when the car is moving. It's driving through a slow moving traffic jam in the summer that has my concern.

Yup, lots of theory to go around, but to answer the original question, no, I don't think anyone's done it successfully. Well, Lamborghini did, I guess, but then in the same situation Ford, Toyota, Ferrari and GM all used conventional front radiators.

So go for it, just please don't re-body the car to look like a Lamborghini.


Aw heck, screw that, if that's what you want then go full Lambo.

http://www.performanceforums.com/forums/sh...he-porn/page125

Same idea as the 914+Jeep,
Better tho.

Click to view attachment

Can't think of a reason why a dual rad set under the targa wouldn't work.

I love to watch this subject resurface. A lot of arm chair engineering and suppositions! While the idea has merits I doubt I would ever do this even "if or when" someone "nails it". If your wondering why then it's most likely because you haven't done one of these conversions. Not trying to be snooty or snotty, just a word from the experience side. First and foremost is the fact that you will spend countless hours refining your design and a very big chunk of that time is thru the "Hell Hole". As we discover, the work in that area is made easy by "QUICKLY" removing the deck lid with just 2 10mm bolts. Mine has come off at least 10 times since it first started and is off again as I type this. (New electrical modification) I don't want to guess how many times it was on and off all together. That being said' if I had to work around a radiator or remove, drain and fill that SOB every time I needed to work in that area I would have abandoned this project long ago. Secondly, why worry about cutting up a front trunk? Once you have a good water cooled system in place you will never regress and re-install an air cooled. Besides, all of those areas can be welded back up quite easily.
I don't wish discourage anyone from trying something new or attempting a new design but I doubt that I would ever go this route even if someone had a proven design just because I know that occasional maintenance is needed in the "Hell Hole". Just my 2 cents.

"RSK must be Peter Harburg's, because there can't be 2 around here."

The most dangerous risk of all - the risk of spending your life not doing what you want, on the bet you can buy yourself the freedom to do it later. - Randy Komisar.
>cal PFF

http://en.wikipedia.org/wiki/Lotus_72

Evolution of design for non conformists.
If you can do it on a budget.
You may have a chance to win.

the advantage of front mount is that once the car is moving you have air moving through the radiator with out needing the fans.

having the radiator out of the airflow you would need the fans to run all the time.

even though there is an negative pressure area at the engine lid I doubt it would be enough to draw enough air flow to cool the radiator enough with out the fans running.

if you a using an engine driven fan then this is not a concern as with a Porsche six or the t4. but if using the electric fans the constant high amperage draw might not be desirable.

If you planning to race it exclusively,a rad mounted in the rh seat area is possible.
Ducting to direct air to and from the rad has minimal weight.
A passenger seat would negate the proposition.

No, not exactly ...

On the air cooled engines, there is a clear separation between the intake side of the engine and the underside where the hot air is expelled.
Without that separation, our aircooled engines would be very short-lived.

I have yet to see any watercooled solution that followed the same principal.

And the (armchair?) engineer in me cringes at that statement.
Because last time i checked each and every "water-cooled" car i know of uses air to expel the heat from the system.

Where do water cooled 911 s mount the radiator

Cause it would seem if it's boxster style , on both lower outside
Bumper area

That they intentionally stayed away from big single right in front style
????????

????

?

I see no reason no to implement what ever current water cooled Porsche s
Are doing

^^ most newer mid engine cars do the corner rads and exhaust the air out the wheel well. Otherwise it cuts into the possible trunk space and exits out the hood or under the car, both are less than ideal.
The 914 doesn't have the space unless you cut into important parts of the chassis structure or make a deeper bumper.

http://www.fiero.nl/forum/Forum3/HTML/000116-29.html

Could mount them at the sides.Something like this.
Do not fear the American Fiero.

Here is my rear mounted radiator in my 904 kit car (engine is a Subaru WRX)
I'm using a stock Subatu radiator and fans, the engine runs at 195 degrees. I'm
using the air coming off the rear deck to supply cool air into the radiator and
having the air exhaust under the car (low pressure area when moving)

Here are the pictures

Click to view attachment
Click to view attachment
Click to view attachment

And that would fit in a 914 how exactly?

There's alot of room for the radiator out in back... unless you want to save your rear trunk. Great looking 904 by the way!

Just to prove a point. As long as you can get the air flowing thru the radiator and exhaust it (air flow) you can mount the radiator or radiators any were.

My NA 2.5 subaru leaves a bunch of room in the trunk as stated. I also don't have any cutouts in front for air flow. It is just the stock holes without the rubber plugs in them. My car has zero cooling problems with it up front. It does exit through cutouts in the wheels wells. It also pretty much wipes out my whole front trunk. If we could get a solution to get headlights in the turn signal buckets. I think the dual radiator boxster setup using the front light buckets would be killer. I think with a flared car you could do those in the engine bay on each side with some inlets. I haven't seen to many inlets on the side of a 914 that I have really liked.

I think if you could have a short but wide radiator. Say 10" by 40"+ it is possible. If you could mount it low in front of a NA 2.5 suby. I think it could work. Only because I know how little it takes to cool mine. It would take some inlets in the rocker at the least. Then some pretty powerful fans to help pull it through. I think low instead of high for working on the motor. If it's up high with a GT lid it will definitely interfere with getting to the motor for basic maintenance. I would love to see it done . I don't see it being me that does it though

I think it has all to do with the size of the motor and the ducting. I would almost guarantee you a 1.8-2.5L could easily survive a small radiator in the engine compartment if there was a proper amount of both ducting with ram air and cowl induction.

How about Targa top mount

As crazy as it sounds , it almost makes sense

My neighbors Baja has the oil cooler in a scoop mounted
Directly on the rear roof

Sure is a beautiful design,tho I can't make out the origin of the car.
Did you do the build personally?

A lot of questions looking for answers.
1 rad or 2?
Up high or down low.Add a scoop or leave it stock?
20Ft of hose or 3?
How to bleed the lines as they make their way forward and back.
Should you make your trunk useless.
It's not real,but should you make a drawing after using a tape measure and Gimp/Photoshop/Draw etc..?
A custom rad or a used one?
Do it like Leo.
DaVinci.
The amount of time and effort every aircooled manufacturer expended is enormous.
1957-65 treks through Death Valley/Denver as a test track with the Corvair.
Real engineers doing real calculations in thermodynamics.
Useful to reference the data gathered as the numbers are real.
The designer of the Tatra wrote an informative book on his designs,buy a copy.

I crunched some numbers.
Based on a few sedans I have available, the point at which the airflow through the grille surpasses the fan cfm is about 15mph. In part throttle low speed around town normal traffic driving almost anything near OEM design will seem adequate. It's at freeway speeds where a higher engine load and increased heat generation takes it's toll. It's the hours on the highway at 2/3 throttle where you'll see temps creep up because you don't have 5x or so airflow forced through the rad.

My 914n6 is an exception. I have 2x 1390cfm from the fans and my break even point is 40mph. But I also have a little oil cooler on the firewall and the SE spoiler lets air flow along the hoses. The ecu triggers 2 speed fans at 203F and 212F. Cruising at 80mph I'd be toast without the forced air.

It seems doable to do radiators in the engine bay, or at the rear of the car at least. Sacrificing the rear trunk to save the front, esp if you could keep just enough to keep the roof back there would be a win.

Just my opinions, but it makes sense to me that with engine tin and sufficient fans you could make it work. I think an engine driven fan may make more sense. I think you might want to use an upright engine so you can maximise the surface areas on either side of the motor. Maybe a centrifugal fan on the crank wheel that blows in two directions into two radiators on either side of the motor? or maybe a slant motor with a rad on one side so you can keep the radiators away from the exhaust.

Logically, if a 3.6 can work, you should be able to do something reasonably powerful, except an air cooled motor has a *lot* of surface area (all those fins!). I think you'd have to pick something physically small-ish to make it fit, but that could still be deeply entertaining.

That's a good idea!

I doubt a 3.6L would work *without* a front mounted cooler. I have yet to see one that didn't have direct airflow over an external cooler.



PS: Hi Fiid!

The question was whether a radiator had been successfully used in the 914 engine compartment. I think the answer is still generally not in a 914, with a lot of discussion of theoretical possibilities. It HAS been done in other cars, for example that Laborghini, or closer to home by Toy-Jet, which put their radiator in an LS1 911's whale tale:


On the more practical side VW bus guys have been out there actively trying lots of different ways to adapt modern engines to their old air-cooled busses. One that was interesting to our discussion was split dual radiators in the engine compartment fed with large scoops on the sides of a bay window bus, augmented by large fans. This worked reasonably well but still tended to heat saturate after extended time on the freeway.


Another bus had huge fans pulling air into split window's engine bay, proved not nearly enough. Yet another had scoops across the underside of a kombi gave good airflow and worked for a while, but scooped up a lot of dirt and crap that eventually clogged things. Another was roof-mounted like a luggage rack, which sounds a bit like the targa suggestion.


The owner intends to camouflage that so it looks like a suitcase or a beer cooler, interesting idea but probably not the best look for a 914. This one actually works really well, it's in direct air flow, but not exactly in the engine compartment.

Obviously these aren't 914's, but it's significant that most of those applications are low to medium powered Subaru engines that are relatively efficient and don't need a huge amount of cooling. A higher powered engine would certainly be more difficult. Basically what's relevant is that the practical experiments indicate that it's really difficult to cool without having access to direct air flow. That means I wouldn't be optimistic about it working in a 914's engine compartment either, but hey, if you think you have a good idea, go for it.

Paul makes a good point re: heat sink. I watched it as I worked thru my cooling probs. And the more efficient your power plant the longer it takes. You think you have it then you don't. It's like chasing your tail. Frankly, I won't know until I've cruised thru the desert @115F w/o a hitch. Everyone of us is running a variation of a variation w/o any "hard" numbers. To Paul's point, you just have to look around to see what works and what hasn't. Good luck

You know what would be an interesting fail safe, If there was a water sprayer in front of the radiator for if the water temp got to a dangerous degree. Obviously you would have to replace the water, but it could avoid a dangerous overheat, and should drop the temps down really fast.

You could mount an oil cooler right behind the 914 drivers head, but there's a lot of hot air there too!

Sure.
Works great,adiabatic cooling,a pal had a system for his van in the '70s that was fantastic.Took it to Daytona to see Yvon DuHamel and Paul Smart.(With our bikes)
A small 12v motor spun a thin sheetmetal disk,water was pumped to an orifice and the water was centrifigually thrown onto a coarse open cell polyurethane foam tube,on the inside.
As the fan was mounted atop the tube,air was forced through the foam into a tubular plenum,where it was distributed to the interior of the van.
Economical,requires water of the fresh kind.Humidity inside rises to near saturation.A turbo charge cooler can be made that works the same.

http://en.wikipedia.org/wiki/Paul_Smart_%2...rcycle_racer%29
http://en.wikipedia.org/wiki/Kawasaki_H2_Mach_IV
http://www.cycleworld.com/2012/06/12/from-...s-daytona-1973/
http://www.vf750fd.com/motorbikes/H2r1.html