anyone ever bothered to measure the running temp of a front-oilcooler?
does it even get hot enough to use it as a heater "replacement"?
brad said that he doesn't like the front-coolers that route the air upwards
with an exit through the trunk lid because you get all the hot air in the car
when the top is off.
question is, does it really get that hot?
if yes, i could route the air from the front cooler under the hood right into
the inside to get some heat.

what'ya'think?

Andy,

What about those days when it's 90+ degrees?

Where will you send the air then?

the car's fresh-air system can easily be modified to route air either inside or on those rare 90+ days, route it out on the side or under or over :-)

real question is, before i put all that work into it, is it even worth trying?
after all, the oil has to run through some 20+ feet of dash whatever lines
before it get's back to the engine. sooo, if the engine runs at 200, how
hot does the front cooler get. actually more important,
how hot does the air get after it went through the cooler ...

Here's a question that may help you find an answer.

Does anyone have a 911 that had a trombone oil cooler that switched to front mounted cooler?
If so, how much difference in temp was there?

I bet it would give you enough warm air, especially if your in the SF area where winters aren't really winters.

andy,

again, take this with a grain of salt. It's only my 1 experience. I don't really know the answer you asked for...

but..... The restriction flowing out of the cooler will significantly effect its ability to actually drop oil temp.
I tried 3 different outlets on my front cooler.

In its most restrictive form, I had the cooler in the front/bumper area. The air passed through the cooler into the front trunk. I (then) had a full sized duct which turned 90 degrees and dumped the exit through the bottom of the trunk. The duct work only extended 6 inches after the cooler before turning 90 degrees down. This was roughly a 6 x 12 inch cooler.

I found even just this one simple 90 degree turn to be so restrictive that I could not drive more than a 30 minute session with out heating the motor into the red...

When I changed my exit, and ducted the same hole straight out of the back of the cooler and gently upswept into the front hood, I dropped my oil temp significantly. In this form, the car could do 1 hour on the track and not reach the temps of the previous set up.

sorry for rambling... but It is my belief that ducting the exit air through the fresh air system or in even a single 90 degree sharp turn, will be too restrictive to give you the cooling you are looking for.

brant

Be carefull!
If a your cooler gets hit and springs a leak, the hot oil will be all over your passenger compartment...

Just a thought

cheers,

Jeroen

good points guys,
the air flow needs to be as smooth as possible, otherwise the hot air will
accumulate backwards and decrease the effectiveness of the oil-cooler.

and i certainly don't want some 8 quarts of oil in my face either.

so, what if (i'm still thinking, can you tell?):

i only need the maximum cooling on the racetrack, so what if
i have the front cooler with a nice, smooth dam going up and exit through
the front hud (perfect cooling), but have the dam with a built in flap
that i can move up to close the upward exit and route the air inside the
car. that way i get the heating when i need it and the cooling when i need it.

mhmmmm ...

The cooler gets plenty hot. The thermostat on my car opens at 185f. I can't hold my hand on the hot side when it's been open for a while, but I can on the cool side....not a very scientific method, but it's all I gots.

I vent my front trunk thusly.
I've built a widget to replace the spare tire cover but haven't installed it yet.

Andy,

JP's cooler is the same one/size I run on the tube car.

I love all the crazy idea's (its good for the site) but... but nothing you can fatham will work to cool a 3.6 liter engine better than a forward facing cooler w/fan. They have NO engine oil cooler. You and Jason where so intrigued by the tranny cooler that you didnt even notice the TWIN 964 coolers in the front. Rogers car would get hot and overheat sitting in traffic (964's have a electric fan on the cooler in the passenger side fender well for traffic situations) Roger used this area to cool his tranny because he was out of stock openings (rules) to cool it.

B

Here's my cheapie oil cooler. It says (shown in next post) to mount ON the shroud ?? I was thinking somewhere else, like Andy. Or use it to cool the tranny?

Lemme havit

here's what I mean...

JP,

are those 3 holes the only venting for that thing?

If so, is it enough?

JP, Brad....

which fluidyne is that. It looks like the therm-hx 400
(DB-30417) ?

If my guess is correct, how is it working out for you.
I just installed a pair of the 30417's in my front trunk, but haven't yet gotten the motor running to test them.

brant

Brant:
The cooler is a 34016.
2 34017s? Whatdaya got in that thing a 502 BB?

Seanery (if that's your real name):

I cut the three holes not knowing if they would be enough venting for the cooler.Ya gotta start somewhere, and uncutting holes is a bitch, whereas cutting more is easy....and that is a structual section.
In any case, they do the trick. I have never seen more than 90c (195f) on my gauge. ufl don't "sit in traffic" and idle....cept in the AX staging lanes.
I'm not sure, but I think that area behind the trunk wall is a low pressure area or pressure neutral at least. The front bumper is a high pressure area, fer sure.
BTW, the "gravel pan" that covers the lower section of that area, is in place. It is a structual part of the car, IMO.

There are a number of "tricks" that can be used to help these motors run cool. I used everyone I could come up with. The most important one is the cuts on the air deflectors around the cyls. I may woof this motor some day, but it ain't gonna be cause I let it get too hot.

A correction. The thermostat opens around 175f rather than 185f as I wrote before. Opens fully around 210f.

Some more stuff....a mixture of opinion and fact.
There is a direct correlation between heat and hp.....burning more fuel produces more power and also more heat.
Heat is a motor killer when it exceeds the thermal limits of an engine. This is (or seems) to be particularily true of an air/oil cooled engine.
What "seems" to be sufficient cooling for 10 minutes of WOT may not be so for 20 minutes of WOT. Heat soak will get ya.
Brad related a problem that a racer he knows
going slower each lap after several minutes of running.
.....heat soak, I fugure....things start to tighten up, leading to more heat, leading to more tightening....yada.

Porsche started using Nikisal clys in their race cars for less friction, better heat disipation, more compatible expansion rates with the pistons...it sure as hell wasn't cause they were cheaper than Brial. They also went to case squirters....which shoot oil on the bottoms of the pistons to keep em cool.

There's more, but I've rambled on long enuff.

Dave (korijo), a few problems with your setup...

First, the engine bay does not exactly have cool high-pressure air in it. (Yeah, higher pressure than some, and cooler than some, but not very of either.) Second, you are pre-heating your cooling air--and also adding at least somewhat to the heat in the engine bay, which pre-heats your induction air.

Your setup there is equivalent of hanging the cooler on the engine lid with a fan. It's been done, and seems to be adequate for at least some track work, but it is not exactly an optimal cooling setup. The best thing about it, IMHO, is the easy installation.

If you really need to keep the engine cool, the front-mounted cooler is the way to go.

I'm going to do something different--yeah, not following my own advice. I'm gonna use an oversized cooler under the rear trunk floor with a fan. Definitely suboptimal, but I think it'll be better than pre-heating my cooling air, and less cutting than a real front-mounted cooler. Plus I won't lose my cargo space (front trunk) and it'll be a pretty stealthy install. I like that idea...

--DD

JP,

I'm sick of too high of oil temp. In the past 15 years, I've tried quite a few different things... water squirting on the fan, different cooler positioning, higher octane fuel, and even aluminum tubing down the rockers to help dissapate heat...

My car is a 2 driver car. Driver 1 goes out for a 30 minute heat race... comes in hot. Sits on pregrid for 5 minutes and then driver two goes out.....

In some of my less effective set ups.. I too have seen my motor make less power (tighten up) with each lap.....

So the new car is a 2.0/6, and I refuse to have cooling problems... I'll run a dang good thermostat, and even with 110F at altitude, I hope to never worry about overheating...
SICK OF IT...

I just cut out the fenders, and am dumping the cooler exits into my wheel wells.. this is gonna be interesting.. can't wait to see how it works....

brant

OK, we're in agreement on heat.

I feel free here to state some opinions with out (maybe)hurting peoples feelings, so I'm gonna.

I woudn't (should I ever get the urge) build a race motor under 2.2L. Why, you may ask (or maybe not )?

84mm Nikasils are the smallest available, AFAIK.
I want a case with squriters. A 7R, 73 CIS , 2.4L case would be ideal.

But enuff of that.....What kind of 2.0L do you have?
What kind of motor did you have when you were experiencing the over heating problems?

Comparing a t-4 with a 6er is apples and oranges from the cooling aspect....and several others.

Back presure (as a result of flow restrictions) on the scavenge side is something to be avoided or minimizeds. Lines, fittings and coolers are all restrictions. Excessive back presure can cause the oil pump to cavitate....which will burn up the pump in short order....not to mention the stresses on the intermediate shaft...load, unload.

I *think* one of these coolers (I don't know the difference between the 34016 & 017 Fluidyne)will do the trick unless you're running something over 220 hp.

I would rather go to one big cooler (say 6 X 24) with AN 16 lines rather than 2, regardless of fitting sizes. Fittings have the smallest oriffices in the system. Also, avoid them sharp 90 deg jobbies. If ya have to use 90s (and I had to use several) get those with the longer radius. I went with Aeroquip.

I ran my 2.4L T motor without any external cooler and never had a problem.... 140 hp or so, but I did use all them tricks. I have never tracked my car with either engine, tho....and, I'm close to sea level.

cool lots of interesting tidbits...
where to start.

previous motor(s): a T-4... short lifed, built, race engine
It was not dry sumped... but no cavitation problems... differnt pump, different one off sump.. plus accusump. Lots of internal oiling mods... still apples and oranges.. but this motor would get hot. --------------------------------

Now, have a 2.0S/6 engine. Updated rods (2.2) lots of oiling mods, upgraded pumps, aluminum block motor.
I always whine about this, but the local vintage club is extremely restrictive... They only allow 914's to have 2.0L/6 motors. Nothing bigger, no 4 cylinders, only 60 series tires, Only metal panels, etc... etc... etc...

Thus I have to run a 2.0
I will however be able upgrade to a twin plug at a latter date, because the factory did..... I'll have a stock 160hp (ish), although I believe some of the 2.0's around here run in the 220 range.

I'll plumb appropriately and have an invaluably experienced race shop double checking my work.. I'm not too worried about the scavenging, and doing it right.

I think the 34016 model is a single pass cooler and the 34017 a double pass cooler. I'll have to find my notes, but I had a long discussion with the fluidyne engineers... surprisingly the double pass is not a huge benefit, but they swear there is no additional restriction.

I definitely don't use 90 fittings, always have used earls in the past... but might try aero fittings this time.

I think I could get away with a single cooer/maybe...
but here is my reasoning:

-I didn't want to be anywhere close to the thermal limit (remember I'm sick of that)
-Its a two driver car at altitude...
-I couldn't run a large single cooler and still fit the mandated fuel cell I wanted to use.. I wanted a large enough cell for enduros, and the rules mandate a cell....

JP.. go look at gunnar racing's site... I'm plagerizing their cooler set up, but this allows me to open up the trunk for the cell...

brant

Brant:

It sounds as though you've done your homework and done your compromises......reality vs ideal....as we all must. Mounting the cooler in the front trunk is a compromise.....air flow vs back pressure....take your pick,eh?

A Troutman or Porsche thermostat is about as good insurance against back pressure as there is....due to it's pressure reilef valving. I found the troutman awkward to mount and plumb....see pic...in the space I had available. Thus some 90s both there and at the cooler.

Vintage racin' groups seem not to be able to get together
on rules structure. Up here guys can run 2.5L 914s....and that ain't enuff against the 240Zs....or so I was told by a 914 vintage guy.

JP,

thanks for your thoughts... and thanks for the picture too...

In my opinion, your smooth 90 fittings are not a problem. It's only the sharp 90's that really kill the oil flow...
Nice picture...

vintage: our club uses 1972 scca GCR.. (except for additional restrictions on rim size [6inchers]) I'll be classed with 1972 911S 2.4 cars... (except they will have souped up motors)

I already know I'll not have the most competetive car, heck the 911's get blown away too from some of the other muscle cars... I was checking lap times and there are a couple of lotus elans running 8seconds a lap faster than my 4cylinder race car.... (72 911's are not really the the top dogs...)

Still... I wanted to build another 914 race car instead of an early 911.. and its not for money anyways..
Plus, I want to come out west and run in the porsche 2.0 challenge... I think the car will be able to hold its own for a metal narrow bodied, non-tube framed C production car...
Plus, I'm going to have a very detailed and light car which should handle pretty well. especially with the trick suspension, and rear monoballs. (I'll find a way to get under 2000lbs, just wait and see)

have a nice weekend..
see ya all monday...
brant