Oil Cooler test location, Air speed results Options

[Trekkor]

Mark came over and we did some testing with his hand held air speed guage.

Many readings were recorded.
Readings are based on a short pass up to 70mph.
Eventually all the front trunk rubber plugs were removed, large exit holes were drilled and a mock shroud was made.

Air speed right at front trunk hole was 56mph.

All holes open with the meter centered on the trunk floor- 17 mph

mock shround in place with meter over exit hole and gravel guard off- 20mph

With a proper shroud this should work quite well.

KT

[Trekkor]

holes are 4.5". The same as for the oil filter on the SIX oil tank through driver side inner fender/engine bay under the relay board. ( whew! )

heres a shot of how the cooler will look mounted.

KT

[Demick]

I can just picture Mark locked in the front trunk with his handheld meter while Trekkor's going down the freeway at 70mph. (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

[Aaron Cox]

why so far back? that is gonna be one huge ass shroud then?

why not all the way up front? and out the bottom? (IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif) AND some trunk space....

[J P Stein]

Look, it's better to get all the air entering the trunk to pass through the cooler and let it bleed off all over hell & gone rather than the opposite.

To get all the air (plus the ram effect), you need a shroud between the front bulkhead & the cooler. That precludes using those little holes as they are too small & spread out. The holes in the rear (plus leakage) are, in my experience, enough venting.

[john rogers]

I think JP and other sare right about the cooler location. It was at the front in all the race cars the factory built and that most all race shops build, mainly for the better air flow and heat control. One thing you have not measured I think is the low pressure under the front trunk area with the front spoiler in place which is probably 40% or so of the force getting the air through the cooler. Since the air is heated, remember it will expand and the vacuum under the car will help it get out, but the further back from the front bumper the exit is, the less the vacuum effect will be. I think Mueller had a thread about this a long time ago?

[Joe Ricard]

.914 cents here but I put my cooler uner passenger side the rocker panel. Oil is cooler than when i had a larger one over the trans. (bad idea)

Anyway got rid of the jack reciever and put some louvers in the rocker panel facing forward.

Does it work???? Well air temp today was 98 distance traveled 186 miles one way average speed 85-90. oil temp 225.

I'll probably move it to the front when I get a spare 1/2 a day.

[McMark]

Trekkor probably would have been fine with just mounting the cooler in the trunk and doing absolutely no ducting or air flow. His temps are already fine 90% of the time. I'm glad Trekkor was willing to think beyond conventional wisdom and try something new. We have a plan that should produce enough oil cooling for whatever six he may install at some point. With his design, he'll also be able to install a front trunk board and still have as much trunk space as a stock car with the spare in place. Works for me.

[Trekkor]

Cooler is now in the car with raw data for you to digest.

The a/x this weekend: I had the air dam over the front vent holes so it was whatever air got sucked out the bottom of the trunk.

never got over 210°. (IMG:http://www.914world.com/bbs2/html/emoticons/clap.gif)


KT

[Trekkor]

Just ran all around the Vineyard Lap®...With open ducting and no air dam.

it stayed super cool. maybe, too cool. (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif)

160-165° (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif)


KT

[URY914]

IMO there is very little air pressure on the face of the cooler located at the rear of the trunk. Once air enters your trunk space at the front it blows all over the trunk before it exits through the cooler.

Look at it this way. Your mother use to put the pie in the window where the air would pass over it as the air blew in. Not on the other side of the room where the door is and the air left the room.

Have you ever seen a race car with the cooler not mounted in the wind stream?

P

[Trekkor]

Put the air dam back over the holes and it went up to 180°ish.

Mind you, I'm not running at 5000-7000 rpm's for 20 minutes straight (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)


Lastly, I cut matched holes into the air dam.
these can be blocked with tape or the stock rubber grommets to regulate oil temp due to outside air temp, etc.

I even cut holes for future brake ductwork.

KT

[DanT]

Trekkor,
That should really help your temps on the big tracks at higher sustained RPMs.
By the way, what cooler are you using and what size AN fittings?
What size dimensionally is the cooler?

Looks great. Some ducting, maybe just a sheet making a false flat floor to the trunk would be all you need. (IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif)

[Trekkor]

No point in debating me...cooler is installed and the data is in. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif)

FYI: I used to get up to 230-240 after the PM a/x runs.
I'd push higher during the fun runs.

Now I ran 210 with no duct work. Two one minute runs back to back, mostly full throttle.

I got close to 250 on the track last week after 15-17 minutes of hard driving ( no cooler ).

I have sneaky suspicion that I will have all the holes blocked except in *very* hot weather.

I'm not telling anybody how to do it. Just sharing what I have done.


Here's the oil lines. "Quick and offensive"


KT

[Aaron Cox]

2 q's -

how do the lines enter the cab from the rear...

and, have you shrouded it yet? just want to see some pics to motivate me to get off my ass...

[Trekkor]

thanks, Dan.

it's a Setrab cooler with -12 line and fittings.
Cooler is 23"l x 5"t x 2"d (IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif)

Or in other words, really, really BIG. (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif)

[Trekkor]

Aaron, no shroud yet.

here's some more oil line pics, though.
comes in right next to the warm air tubes ( capped ).

KT

[Trekkor]

...Here it comes right through, below the backpad and along the passenger seat and floor.


KT

[Trekkor]

I will report back with oil temps after my D/E on Friday...



KT

[lagunero]

Trekkor, is there an advantage to having the thermostat so close to the cooler, as opposed to closer to the engine? Longer travel for the oil?