Auxiliary radiator, or auxiliary oil cooler?

volvoclearinghouse wrote: You know, Ford put these engines in lots of medium duty trucks.

This is why I think its a flow issue. Those trucks tow heavy E36 M3, on steep grades, at lower speeds (less airflow), with what is probably a smaller/less efficient radiator.

Yeah, that's one of the reasons I recommended the Volvo OEM setup. For oil, I like crimped hoses a whole lot more than hose barbs and clamps.

Knowing the coolant and oil temperatures would be helpful.

Kenny_McCormic wrote: Knowing the coolant and oil temperatures would be helpful.

Sure would!

We don't have that.

We don't know oil temps, because we have no oil temp gauge. At the last race, we were cooking the water in the rad around 230-240 degrees.

Tuna suggested the cutouts in the fenders, to help evacuate the air, so I made these on each side (cut freehand with an angle grinder).

We also removed the inner fenders, this was a couple of years ago.

(The duct tape on the tire is to prevent the wire belting from cutting our hands. These are the trailering tires, they're about 100 years old, but they hold air and are round...ish)

Another shot of the engine, radiator removed here:

And here's the front of the car. The front bumper has been removed, and there's an air dam under the radiator to help "scoop" air up. The air ducts on the sides lead to brake cooling lines.

Went out and looked at it tonight. There's no room to mount the Honda radiator I have, but plenty of room for an oil filter adaptor and a smaller oil-air cooler. So I think that's what we'll do. I have the parts list for a cooler setup we put together on paper a few years ago but never pulled the trigger on. I think it's time.

I also do have several heater cores from Volvo 122s. These are pretty beefy cores, and I might plumb one in to the heater circuit for a bit of extra cooling capacity.

Here's the oil cooler BOM Tuna made for us:

I can make it up:

http://www.summitracing.com/parts/aaf-all26702/overview/

http://www.summitracing.com/parts/TRD-1313

http://www.summitracing.com/parts/trd-2269/overview/

And then some 3/8" lines.

I put a Monte Carlo heater core on my Acura K20A2 and completely eliminated my overheating issues. It adds about 25% more cooling, based on the results I have seen. A very easy modification and it only cost less than $100.

A heater core can suck a lot of heat out, two would probably bring you down to 210 no problem.

Also, I wonder if a better belly pan would aid airflow through the engine bay. Gut feeling is to better seal up the area forward of the cross member. I'm far from an expert there though. Easy experiment with some free coroplast election signs.

Kenny_McCormic wrote: A heater core can suck a lot of heat out, two would probably bring you down to 210 no problem. Also, I wonder if a better belly pan would aid airflow through the engine bay. Gut feeling is to better seal up the area forward of the cross member. I'm far from an expert there though. Easy experiment with some free coroplast election signs.

That was another improvement we made this time around. I cut some thin sheet metal scraps I had laying around and bolted them on either side of the radiator, to channel air into the radiator and not allow it to go around.

We've done a LOT of work to improve cooling prior to this race, so much so that I wouldn't be surprised if it'll be fine. Still, I'd hate to get to the race and still have problems. The car's not street legal (for many reasons...) so we're limited as to the testing we can do with it. I'm definitely going to plumb in a heater core of some sort, and take a poll on our Tunachucker email thread about the oil cooler. I have a good spare trans cooler (one of the good, radiator style ones, not the cheap "tube and fin" type) we could probably use, so it would just be the cost of the filter adapter ($40) and some lines and fittings. Probably under $100 all in.

Good plan. The cheapass oil cooler and the auxiliary cooler should bring temps under control. If you have an IR temp gun, you can get some idea of roughly what the oil temps are by pointing it at the bottom of the oil pan.

Here's another idea, how about some aggressive hood venting? Have some inspiration:

We talked about some venting at the back of the hood, by the windscreen, until I pointed out that that's typically a high pressure zone used to induct air for the HVAC system. Some vents behind the radiator, in front of the air cleaner, off to the sides might help though.

What rpms are you running while on track? One thing I found on a couple BBCs I had was that with underdrive pulleys, the engine ran cooler at speed than with the stock pulleys. It may be possible that you are spinning the water pump too fast and there may be a bit of cavitation happening. A fan shroud would help as well, your fan is a bit too far from the radiator. Just a couple ideas I had.

81cpcamaro wrote: What rpms are you running while on track? One thing I found on a couple BBCs I had was that with underdrive pulleys, the engine ran cooler at speed than with the stock pulleys. It may be possible that you are spinning the water pump too fast and there may be a bit of cavitation happening. A fan shroud would help as well, your fan is a bit too far from the radiator. Just a couple ideas I had.

We do have a shroud, it's not installed in that pic but it is there.

The 460 spins a maximum of 4000 RPM, on the one straight, at a ground speed of about 107 mph. Most of the time it's around 2500 to 3500.

So, with a shroud, is the 1 inch from radiator to fan still the recommended spacing?

And, have you checked out the fan clutch?

Take a look at how Nascars cool their 900 hp engines. I think ducting the air from the grille to the radiator is important as well as letting the air out. They do it by letting it out through the wheel wells. Could that fan be blocking air flow ? How about slowing the water pump down ?

I would be worried about 3/8" lines for the oil cooler. That engine surely takes a lot of oil flow, I'd look at 1/2".

I recently put a little tube-and-fin oil cooler kit with an electric fan into the BMW E21 I track, running an E30 2.5l motor. I think it might have been a Derale.

The motor comes stock with an oil cooler, but it's mounted under the radiator and is vulnerable as hell to getting knocked off at the track.

My oil temp sensor is in the oil pan and running the engine at high rpms heats the oil fast. I run 15W50 synth like you. I put the new oil cooler up in the nose off to the side of the radiator so it gets good air flow, and the fan helps too. But it has 6AN fittings and hose lines to the block, which isn't a lot. It seems to keep the oil temp down to a steady 240 degrees, but I may yet rebuild it with something better.

OK, quick/ dumb question: Will THIS STUFF work with motor oil? It says it's for transmission fluid, and rated to 500 psi. It should be oil proof, right?

ross2004 wrote: I would be worried about 3/8" lines for the oil cooler. That engine surely takes a lot of oil flow, I'd look at 1/2".

I'm coming in a bit late, but this caught my eye.

460s are already a bit crippled in that they are not priority main oiling. I strongly recommend against an oil cooler unless its something like a finned aluminum pan. Do not (in any way) divert, change, or reduce oil volume or pressure on a 460 unless you do some comprehensive internal mods. Seriously. Focus on water temps.

A sub-300-hp 460 should cool just fine through a 5 gallon bucket. Your radiator is obviously ample.

This is an airflow or tuning issue, I promise.

I'm going to ask basic questions and I don't want you to think I'm insulting your intelligence.

Lower rad hose have a spring in it?
You're sure the water pump is moving water as it should?
Did you measure actual temp or just relying on the gauge?
Where is the temp sensor? If its in a head, 230-240 is perfectly normal for a 190 stat.
Are you certain the pulley isn't slipping? Aftermarket pulley? If so, did you sand the groove?

The only other thing that is coming to mind right now is an excessively rusty water jacket in the block/heads. There are a couple things you can try to narrow down some issues.

Drain about half your coolant and replace with water to increase the amount of water in the system. If the temperature reduces, its a heat transfer issue. If it increases, its a system pressure issue.

Remove the stat. Temp decreases, its a water flow issue. Temp stays the same, its not a flow issue (unless you have a restriction or collapsing hose)

Remove the hood. Temp decreases, its an airflow issue. Temp stays the same, its some other issue including the possibility of fuel tune.

Another thing I would test is the vacuum advance diaphragm. A busted diaphragm will show up as retarded timing in the part throttle range.

I know this is Lemons, but something doesn't compute. You might be able to mask the issue with heater cores or more holes in the hood, but something is not right an I hate to see a band-aid fix.

In reply to curtis73:

As always, I appreciate your input and do not take it as snarky. I'm an engineer myself, so I tend to be relatively straightforward which can offend some people, but helps get straight to the point.

I do know about Ford's oiling issues on, well, everything. The cheap and dirty "fix" for the 460 is to install a high pressure and high volume pump, but that requires hardened/ beefed up oil pump drive components, which is a path we'd rather not go down, for now. As I've said, we have a super tall rear end so the engine never sees the bright side of 4K RPMs. We did install a windage tray and I have a mark on the dipstick indicating the bottom of the crank weights, so we know exactly where the oil level is. The engine maintains good oil pressure (my usual metric is at least 10 psi per 1000 RPMs) at all times, even under cornering.

To directly answer your questions about air cooling:

1) Both radiator hoses have internal springs. Both are relatively new.

2) With the upper radiator hose removed, the engine pumps water like nobody's business out of the hose, and it increases as RPM increases.

3) We have a water temperature gauge that fits into the stock location on the intake manifold, in the front of the engine, near the thermostat. We have not calibrated the gauge, but it is new-er.

4) Pullies are all stock, new belt, alternator charges good and fan spins well. Replaced the fan clutch, too.

5) We don't run coolant, only straight water, per LeMons rules. After this next race I'll probably drain and add 50/50 to it for storage issues. Also, I have been fluyshing and refilling the cooling system, and removing quite a bit of brown from it. I had been concerned about crud in the cooling system (the radiator is newer, and it's been flushed as well) so we're addressing that.

We have been running a 180 degree t-stat. I do not believe in running no thermostat. However, many guys seem to like running restrictor plates in place of the stat. So I drilled (4) 1/4" holes around the center of the t-stat. The engine gets up to about 185 when idling, then you can see the gauge go down to about 180 as the t-stat is apparently opening (this is another verification of the gauge being correct).

Now, I just did this t-stat drilling, we haven't raced on it like that yet. Likewise with the major block flushing. And the radiator sealing around the cowl, new head gaskets, relocating the tranny cooler, and about a dozen other things we've tried in a "buckshot" approach to better cooling.

Unfortunately, as I'd said, our capability to do testing (other than idling the engine and revving it in the driveway) is pretty limited due to it's non-road-legality. We have done some tuning with an A/F meter in the exhaust and richened up the carb (Edelbrock 1406) quite a bit. Throttle response seems excellent and the engine never wants for power. We don't have the vacuum advance connected- my understanding is that's mainly for part throttle cruising efficiency. Racing, we're either at WOT or idle, essentially. Ignition timing advances with RPM and seems to behave as it should (electronic ignition, no points).

I do plan on reviewing all the vacuum connections to ensure there's no leaks...there are a couple of plugs I want to check (not because they're suspect, I just haven't laid hands on them yet) and the vacuum line to the transmission (C6, auto).

One last thing- I thought the oil cooler was a parallel circuit, in that it would not impeded the flow of oil to the engine. If it is in series, however, then I agree with you- we absolutely should not touch that. I guess I need some clarification/ education about that.

Will move forward with the additional water cooling, but let's discuss the oil cooler some more.

Thanks (to everyone) for their input so far!

volvoclearinghouse wrote: OK, quick/ dumb question: Will THIS STUFF work with motor oil? It says it's for transmission fluid, and rated to 500 psi. It should be oil proof, right?

Yeah that should work. Anything that holds ATF will work (chemically) with engine oil and vice-versa. You just gotta be careful not to use a lower-pressure ATF return line for an oil cooler, Toyota once made that mistake from the factory, surprisingly the lines lasted a few years before they blew up.

volvoclearinghouse wrote: One last thing- I thought the oil cooler was a parallel circuit, in that it would not impeded the flow of oil to the engine. If it is in series, however, then I agree with you- we absolutely should not touch that. I guess I need some clarification/ education about that.

Series is my understanding, but I could be wrong. I have a generic one at home I'll look at later.

A non-thermostatic oil cooler is entirely in series. A thermostatic oil cooler is still basically in series but flow can be split between the cooler and lines and a bypass path in the sandwich plate. Also keep in mind that most engines have some kind of bypass valve either in the filter or at the filter port that will send unfiltered pressurized oil back to the engine if there's too much resistance at the filter port.

In any case, I wouldn't consider anything less than 1/2"ID lines for that engine. I use 1/2"ID on my little I4.

You can get nice used NASCAR hoses on ebay for silly cheap. -10 is what they use for fuel and you can find many various lengths of it. You could cobble together a complete system for under $150 easily. What kind of oil psi do you have now? Expect to drop 5-10 with a cooler.