Motorcycle Twin Radiators for cheek rads?

[EDMO 1078]

Has anyone explored the possibility of using twin motorcycle rads for cheek rads?

I am thinking that the rads for an 1500 to1800 cc or so might work for the Soob -81, and maybe from some smaller version for the 912 and 582?  Seems like the Chinese aluminum aftermarket rads are cheap?

any comments?

EdMO

Edited 9 Mar 2014 by Ed In Missouri

[akflyer 1427]

That's what was on mine originally and they were only a 2 core radiator and I was never happy with the cooling. If your going to go in cowl, you need the 4 core (or 4 pass) to get enough cooling out of the size of radiator you can stuff in there. At least on the tight cowl that came with the c model. Maybe your subie cowl will have enough room you can put the larger 2 pass motor scooter rads in there.

[EDMO 1078]

I was thinking - that gets me into trouble sometimes - that if they cooled an 1800cc motor on a bike in stop n go traffic, then they should cool a plane on the ground or in air.   Even if mounted farther back in cowl, if you have ducting to them?  I agree on the more cores, the better cooling.  Do they make a 4 core?

I will have to check my VW Rabbit rad - it is probably 2 or 3 core?

EDMO

Edited 9 Mar 2014 by Ed In Missouri

[Av8r3400 1178]

Automotive (or motorcycle) engines run at a tiny fraction of their maximum output for the majority of the time in an automotive application.

 

In an aircraft, the engine is operating at a very high percentage of it's maximum output, most of the time.

Edited 9 Mar 2014 by Av8r3400

[allonsye 85]

Ed -

 

I've a source for these:

 

NIB Aluminum Spectra Premium 94553 Heater Core Without A/C 1973-86 Chevy Truck

 

They're 6.5 x 8". Light as a feather. $15 each -- 1/2 what the auto parts stores charge. Ping me and I'll send you their email addy.

 

Combined, they're dimensionally same cooling area as the spendy vertical, reduction drive mounted  Rotax radiators and enormously cheaper.

 

I've been vexed with coming up with a solid way of mounting them that is not affected with engine movement and vibration.  The PO's on mine installation was copper and the brackets all cracked, mounted off the eng mount and the reduction drive.

 

Anyways, I think an installation solution is to glass-in receiving pockets or brackets behind the cowl inlets that these will slide into with sealing baffles. A "Y" connection above the gear box, off the fwd eng mounts to support the weight of the lines and coolant and create parallel simultaneously flow to both radiators.

 

Much cheaper solution than the $400 kitfox belly setup (including the radiator cowl) and would look better.

 

On the other hand though, since you're cooling a Subie, I don't know if it'll be enough cooling for you. I thinking in terms of a 582. Have you looked at the UL912 setups to mimic that?

Edited 10 Mar 2014 by allonsye

[Av8r3400 1178]

A 912 only has liquid cooled heads.

A Subaru will need much more cooling capacity.

[EDMO 1078]

Thanks for the info.

Better check the fins and tubes on these - I have read that heater cores don't cool the water as much as a radiator the same size.

A/C evaporators from Chevy - not Ford tho - were used as cheek rads by some conversions, and they are supposed to work well.

Since the EA-81 is 1800cc - more than 3 times the volume as a 582, I don't think they will interchange - they might be an added cooling for a belly rad on the Soob.

Appreciate the thought.

EDMO

Guess the 912 might be about the same as 582 if it only has head cooling.  Thanks.

Edited 10 Mar 2014 by Ed In Missouri

[allonsye 85]

Just saw these - slightly larger:

 

http://www.ebay.com/itm/Spectra-Premium-Industries-Inc-94553-Heater-Core/131072109092?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20466%26meid%3D5376419432385012618%26pid%3D100011%26prg%3D9138%26rk%3D0%26rkt%3D10%26sd%3D321319584831

[Av8r3400 1178]

 

Guess the 912 might be about the same as 582 if it only has head cooling.  Thanks.

 

 

Kitfox uses the same belly radiator for both.

 

My friend who used to have the Suby powered Kitfox used a VW radiator (I think), mounted as a scoop on the belly.

 

Here is a similar setup on a Rans S7 under construction.

 

[lostman 198]

I would say that the ones in the link above are very close to the ones in the Pursang for size, although I'd be willing to bet they are much lighter. In my installation they are held off the engine by heater hose, connected to solid mounts on either end, so that basically about two inches of hose insulates the vibration from the engine and everything. There are three pieces of hose per radiator. They work really well and I haven't seen above 180 degrees at any time, even after a climb to 11,500 from 5,000' at full throttle the day before yesterday. Admittedly the temp on the ground was only about 60 degrees but I was still impressed it worked that well.

[EDMO 1078]

I would alsmost bet that the ones on the Pursang are AC parts that Stratus used, not heater parts.

I have never understood the horizontal rad working - air is not supposed to turn 90 degrees - but it may be trapped.

My Soob has a VW Rabbit rad which was placed at an angle below the firwall and inside the cowl.

Rans had one at the top of firewall angled, and many little vents in the top cowl.

Whatever works - works!

EDMO

[Av8r3400 1178]

The photo above that I posted, the air enters the opening and has to leave the cavity through the radiator.  This slows the air moving through the radiator to slow enough to allow the heat to transfer more efficiently.  

[dholly 718]

I've been vexed with coming up with a solid way of mounting them that is not affected with engine movement and vibration.  The PO's on mine installation was copper and the brackets all cracked, mounted off the eng mount and the reduction drive.

 

Anyways, I think an installation solution is to glass-in receiving pockets or brackets behind the cowl inlets that these will slide into with sealing baffles. A "Y" connection above the gear box, off the fwd eng mounts to support the weight of the lines and coolant and create parallel simultaneously flow to both radiators.

 

The inlet radiators on my Aerotrek are mounted by brackets to the lower cowl with Dzus fasteners (which must be undone to remove the lower cowl). Attached is a stock photo that will give you some idea, I can walk out to the shop and take detailed pics if you need.

[EDMO 1078]

Thanks Doug - real good photo.

EDMO

[allonsye 85]

The inlet radiators on my Aerotrek are mounted by brackets to the lower cowl with Dzus fasteners (which must be undone to remove the lower cowl). Attached is a stock photo that will give you some idea, I can walk out to the shop and take detailed pics if you need.

Helpful. Thanks for sharing. I'm curious - what are the dimensions of those radiators?  And, are there inlet seals keeping air flow from going around - forcing through radiator?

 

I like the dzus fastener idea. This setup appears efficiently vibration isolated.

Edited 17 Mar 2014 by allonsye

[lostman 198]

The radiators on Pursang are some that John had a local radiator shop fabricate. They are thick and very heavy copper and steel. Basically they appear to be half of a normal radiator. Next time I pull the top cowling off I'll measure them and see how big they are. I'd guess they are about 9"w x 12"h x 3" d. I do believe he told me they are dual bypass but I don't remember for sure. I just know they are heavier than they would have to be. If I could find something in aluminum that's the same size I wouldn't mind the "diet" on the plane. Especially since it's supposedly still quite nose heavy according the John. One of these days I need to find scales to do a W&B though.

[wypaul 448]

Doug, does the oil cooler attach the same way?  

[akflyer 1427]

The radiators on Pursang are some that John had a local radiator shop fabricate. They are thick and very heavy copper and steel. Basically they appear to be half of a normal radiator. Next time I pull the top cowling off I'll measure them and see how big they are. I'd guess they are about 9"w x 12"h x 3" d. I do believe he told me they are dual bypass but I don't remember for sure. I just know they are heavier than they would have to be. If I could find something in aluminum that's the same size I wouldn't mind the "diet" on the plane. Especially since it's supposedly still quite nose heavy according the John. One of these days I need to find scales to do a W&B though.

 

Randy (suberavid) had aluminum ones made for his fat avid.  you may drop him a note and see who did them and get a price from him.  I think they were sourced local but I cant swear to it.  I do know they are very nice, not cheap, but work very well!

 

[EDMO 1078]

I believe Randy said he paid $700 for his.  I saw Chinese aluminum MC rads for a lot cheaper.

EDMO

Edited 17 Mar 2014 by Ed In Missouri

[akflyer 1427]

and sometimes we get what we pay for   Especially when ordering from China.  You have NO clue what alloy your getting.  Saving a couple hundred on a radiator that may fall apart from shitty welds or a really crappy alloy will probly end up getting expensive quick as you know damn good and well that when it fails it will NOT be when your 8,000 over an endless dry lake bed you can land the space shuttle on.

 

[EDMO 1078]

Yes, Leni, I agree!

EDMO

[allonsye 85]

http://www.griffinrad.com/AirSupportVehicles/index.php?tid=7

http://www.griffinrad.com/contact.php?tid=29

 

These folks say they will build whatever you want in an aluminum radiator.  There's at least 3 or us on the board looking for new radiators. Perhaps a group buy can be arranged. 

 

Here's an interesting article about radiator modification to improve cooling. The more "passes", the better:

http://www.eaa.org/experimenter/articles/2009-06_radiator.asp

Edited 17 Mar 2014 by allonsye

[dholly 718]

Doug, does the oil cooler attach the same way?  

 

It's a bit different than the rad mounts. Air is fed thru a NACA duct on the co-pilot side lower cowl into the cooler which is situated longitudinally in a fiberglass mount inside the cowl. You have to loosen the two lock nuts on the cushion mounts to remove the lower cowl, the cooler just floats therewith the cowl off.

[dholly 718]

Helpful. Thanks for sharing. I'm curious - what are the dimensions of those radiators? And, are there inlet seals keeping air flow from going around - forcing through radiator?

I like the dzus fastener idea. This setup appears efficiently vibration isolated.

Here's some pics with measures. Also, I misspoke earlier about the Dzus fasteners on the rad mounts. You can see in the photos they are fastened to the cowling with Allen head bolts. Haven't had all that apart in a while, been working on the fuse and wing repairs,

Edited 18 Mar 2014 by dholly

[dholly 718]

Couple more.....

Edited 18 Mar 2014 by dholly