Any successful radiator in engine compartment conversions?, Or other than front trunk installs? Options

[Mueller]

Crazy idea time.....

Still have "something" up front yet sized much smaller due to using the coolant lines that go up front as heat sinks....

Not easy or cheap to fabricate and more spots for leaks...then you have to worry about extra resistance/friction for the water pump to deal with.

[DBCooper]

I've seen finned aluminum tubing a bit like that in a process plant on the Gulf coast. Thought about trying to find it for my car when I was planning for the V8, but never did.

Found it, here:

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.vulcanfinnedtubes.com-2618-1421716083.1.gif)

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.vulcanfinnedtubes.com-2618-1421716084.2.gif)

I just googled "longitudinal finned aluminum tubing." I think it's high-dollar specialty stuff (petro-chemical plant) but ask, for the tiny quantities you'd need I'm sure they'd have some odd lengths for sale cheap. The one I saw was thin walled and actually had a lot more thinner and shorter fins than that, so if that doesn't work try some of the other suppliers. And if it sticks down too much you can just grind off those fins.

[Dave_Darling]

Talk to Chuck at Elephant Racing in SJ. They do mandrel-bent finned tubing for 911 oil cooler lines. The tubes are actually threaded, IIRC, but the threads act like little fins.

I kind of doubt you'll get a whole lot of cooling just from any set of lines, but I guess every bit helps.

--DD

[timothy_nd28]

Trane has been using this for decades, highly highly efficient with heat transfer but I worry about the pressure drop.

[Mueller]

Trane has been using this for decades, highly highly efficient with heat transfer but I worry about the pressure drop.

Interesting stuff....

http://www.achrnews.com/articles/90183-the...eat-coil-debate


Seems like this might be a thermal issue that a professional HVAC designer should be involved in!

[Mueller]

New Lamborghini Huracan has rear mounted radiators...now to find a picture!

[Brian Mifsud]

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.

Exactly ...

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.
(IMG:style_emoticons/default/shades.gif)

Adding to this.. the 911 engine uses Mechanical Energy to run a Centrifugal Blower.
It moves MEGA cubic feet per minute by sacrificing many horsepower. Estimates are up to 16HP:

http://forums.pelicanparts.com/porsche-911...g-fan-cost.html

Think about how big a 16HP electric motor is...

In a 914, you need brute force to pull the air down and through the engine bay.

I think this is the fundamental reason why a front mounted radiator is far more efficient.

[rick 918-S]

Scott Thacher was the guy who showed up in WCR 05 with his "In Bay" NA scooby conversion. He drove it from MD to SoCal and back!
#'s dont always tell you if it will WORK.

Thread

(IMG:style_emoticons/default/agree.gif) Traveled with him. The car was completely back yard engineered before Renagade even thought about it. Stock Suby radiator just ahead of the engine. Small scoop on the pan pulling air off the road. We were stuck in construction at way over 100 deg. I had to shut my engine off. He was driving around us through the ditches.. (IMG:style_emoticons/default/screwy.gif) It will work.

[Mueller]

Adding to this.. the 911 engine uses Mechanical Energy to run a Centrifugal Blower.
It moves MEGA cubic feet per minute by sacrificing many horsepower. Estimates are up to 16HP:

http://forums.pelicanparts.com/porsche-911...g-fan-cost.html

Think about how big a 16HP electric motor is...

In a 914, you need brute force to pull the air down and through the engine bay.

I think this is the fundamental reason why a front mounted radiator is far more efficient.

hmmm, maybe we are looking at this the wrong way....perhaps it should be suck and not blow? (IMG:style_emoticons/default/screwy.gif) (IMG:style_emoticons/default/av-943.gif)

Radiator setups with pull type fans are more efficient than those with pusher fans...

[Chris H.]

Yes, always pull air, never push (Mike Bellis).

Some of the pics are missing from Scott's build but I think I have them somewhere. Let me look. Just need a decent sized rad and strong fan/fans. I think he mounted it pretty low.

I also toyed with the idea of somehow using the heater tubes in the longs as a secondary source to blast air onto a mid ship rad, bringing the air from the front. Couldn't figure out where to duct it without cutting and the cowl vent seemed too small so I abandoned it, but maybe it will turn a light bulb on for someone else...

[Andyrew]

Scott Thacher was the guy who showed up in WCR 05 with his "In Bay" NA scooby conversion. He drove it from MD to SoCal and back!
#'s dont always tell you if it will WORK.

Thread

(IMG:style_emoticons/default/agree.gif) Traveled with him. The car was completely back yard engineered before Renagade even thought about it. Stock Suby radiator just ahead of the engine. Small scoop on the pan pulling air off the road. We were stuck in construction at way over 100 deg. I had to shut my engine off. He was driving around us through the ditches.. (IMG:style_emoticons/default/screwy.gif) It will work.

Its all about proper shrouding and airflow IMHO

I think engines under 200hp can support something like that.


I have been considering the aluminum tubes for a while but I really dont think we would see more than a 5 degree heat loss and only while moving. If your sitting on hot asphalt rolling slowly and the asphalt is 130 deg....your really not going to get any benefit....

You can probably get more benefit from having small inline motorcycle radiators in the fender wells with some fans that kick on. I am going to have one for my a/w intercooler (similar to Miked but without direct airflow)but I have more fender space than most anyone.


The other thing I think is electric water pumps to flow more coolant at low speeds, Like the Daves one I posted earlier (cant search now)

[worn]

water is a more efficient medium than air so

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.
(IMG:style_emoticons/default/rolleyes.gif)

You have to admit that the phase change provides a cushion: if all else fails it ca boil over.

[914forme]

Motorcycle Rads I have thought about several times. I even took time to look for small rads to mount in my front fenders. Newer bikes are using curved rads to get more surface area in a narrower space.

The one I am still looking for was as a kid I remember an add in the back of Hot Rod. Claimed to cool a 454 with a super small rad, like a 12x12, octagon thing.

Now maybe it was all made up, as a 454 could be cooled while idling and coasting down hill at 100 miles an hour.

Love to find out if it actually worked though as I think fender rads would be a very nice touch. Much like Brant's oil coolers. I keep trying to figure this one out. And yet to do it. And right now, I am just in the mood to get the car running and get to driving.

[Brian Mifsud]

hmmm, maybe we are looking at this the wrong way....perhaps it should be suck and not blow? (IMG:style_emoticons/default/screwy.gif) (IMG:style_emoticons/default/av-943.gif)

Radiator setups with pull type fans are more efficient than those with pusher fans...

Somebody already did the work years ago either on this forum, or on "Rennlist", but it's very useful to understand where the Vacuum is in and around that engine bay at speed. Typically, you'd expect a low pressure area behind the rear window due to the sudden transition of the roof ending at the engine compartment "intake".

Under the car, the little skirt Porsche put in front of the bottom edge of the engine compartment is supposed to do the same thing, create a low pressure region to help "pull" the air through the fins as pumped by the engine's scroll/squirrel cage blower. I've always wondered which area had a lower pressure "vacuum" at a given speed.

I don't see a compelling reason for air to flow through the engine bay on it's own without being pumped in some manner. Years ago, at an autocross, I had to laugh at the racer's solution.. taking furnace ducting, and running it straight through the front of the car, trunk, passenger compartment, and ending aimed directly at the blower which had blades removed to minimize parasitic drag and lost HP. The car's sheetmetal was certainly hacked up. Now THAT was taking the bull by the horns....

[Chris914n6]

Looking at racing rads for toyota celica/mr2/spyder ran across racing rads for motorcycles that were not curved, if someone was considering doing multiple small rads now is a good time to hit ebay.

[Andyrew]

You talking about these puppies?
http://www.ebay.com/itm/DUAL-CORE-2-ROW-MO...735&vxp=mtr

Ya thats what I am going to use for my A/W Intercooler in my fender.

[SirAndy]

Years ago, at an autocross, I had to laugh at the racer's solution.. taking furnace ducting, and running it straight through the front of the car, trunk, passenger compartment, and ending aimed directly at the blower which had blades removed to minimize parasitic drag and lost HP. The car's sheetmetal was certainly hacked up. Now THAT was taking the bull by the horns....

Was the car yellow? If so, that is Rich Bontempi's class winning 180HP 1.8L ...
(IMG:style_emoticons/default/driving.gif)

[Chris H.]

You talking about these puppies?
http://www.ebay.com/itm/DUAL-CORE-2-ROW-MO...735&vxp=mtr

Ya thats what I am going to use for my A/W Intercooler in my fender.

Some come as a pair and they measure 4.5 X 13 each depending on the one you pick..I think that's about the width of the front trunk area. Man it would be nice to put a couple of those in there and get most of my trunk space back. Could stick them right in front of the opening and vent them just like an oil cooler. Not sure if they would be enough to cool my engine though. Be like having ONE 9x13 rad I guess... Might need one or two more. The small fans sure are pricey!

[Dave_Darling]

...taking furnace ducting, and running it straight through the front of the car, trunk, passenger compartment, and ending aimed directly at the blower ...

That's the road-race solution. It stems from rules that were originally written for Little British Cars--you were allowed to duct air from the headlight buckets to the cooling fan.

Works well at speed, but not so great at idle or at low speeds.

I talked to the late Chuck Forge about it, and the cooling fan with most of the blades removed. He said he ran a full fan once to compare--and it felt like he was dragging a trailer around the track with him! Chuck used fans with, I think, 2 out of every 3 blades removed. I remember Rich using fans with all the blades removed. Probably one reason that Rich quoted higher power levels than Chuck did.

--DD

[Brian Mifsud]

Years ago, at an autocross, I had to laugh at the racer's solution.. taking furnace ducting, and running it straight through the front of the car, trunk, passenger compartment, and ending aimed directly at the blower which had blades removed to minimize parasitic drag and lost HP. The car's sheetmetal was certainly hacked up. Now THAT was taking the bull by the horns....

Was the car yellow? If so, that is Rich Bontempi's class winning 180HP 1.8L ...
(IMG:style_emoticons/default/driving.gif)

Now that you mention his name, YES it was Rich's car. He knew what he was doing for sure.