Cooling for Open Track and sustained high speeds...

[Fast GTO]

I'm new, about to pick up an 03 10th Anniversary TR KB Cobra this weekend which I will be bringing to Germany with me for us on the autobahn and occasional open track events. I'm not that familiar with the Cobra setup because I am coming from a Speed INC built 416CI N2O GTO. What I have gathered from searching and reading is that cooling is a main concern when in boost for sustained periods of time.

[ame="http://www.youtube.com/watch?v=uSkYyw4_pGk"]YouTube- 416 CI L92 GTO on 200 shot N20 goes 10.16![/ame]

Right now I am considering the use of Meth in order to make these sustained boost events safe. There seems to be two thoughts on this. First is that it doesn't benefit you for lowering IAT's and is thus a waste of money. The other opinion I have been getting is that it does reduce temps, but only in the combustion chamber where it can't be measured easily (and thus prevent detonation). All agree it allows for tuning on pump gas (91/93) as if you were using 100+.

So are the benefits worth the cost for someone who wants to do some open track and go WOT on the Autobahn at 100+? I keep reading that cooling is the main concern for this type of driving (open track and sustained high speed high RPM loads). Car already has a Gords H/E but I am also considering a larger radiator.

I've got the opinions of Speed INC and Kurgan on this already but reading around various forums it is still confusing since some say it is a complete waste of $$ that could be spent on other modifications that are more useful. If the money should be spent elsewhere where should I spend it?

Current tune is on 93 and makes 602rwhp with 17psi. I am getting a retune and will have one made for open track.

 

[Jimmysidecarr]

{1}
Evans waterless coolant would save your bacon if temps climb too high.
link -> Coolants » Engine Cooling Systems

The NPG+ is going in mine as soon as I am healed and ready for track events again.

I really don't understand why it isn't in wider use in the performance community. Cost perhaps?
Some say if they had to add coolant because of a leak, the can't use water.
That's pretty bogus if you ask me. When was the last time you got sidelined with a coolant leak and had water handy? What's going to keep it from leaking out too? You get towed or you risk trashing an expensive engine.

The Evans allows you to run a zero pressure system, which = leak potential is negligible.

370F boil point!!! This means even if you run 240F you will not boil coolant! There will also be no detonation producing hot spots from steam caused vapor barriers. The coolant remains liquid, and in contact with the metal it is removing heat from.


{2}
Box in the radiator. You want all the air coming in going THOUGH the rad and not leak around it. This raises the air pressure in front of the rad and lowers it behind it... thus air gets though easer and in greater volume. Enhanced(larger) lower air dams and venting help lowering the engine side air pressure.(more CFM)

A special note
Yes I have a larger rad. but a thicker rad resists air flow more than the same size stocker. The management of air flow becomes essential. The inlet air can be maximized by boxing.(we only have just so much air coming in)
The engine compartment air pressure needs to be as low as possible. Air dam depth and width, hood vents, fender vents.

{3}I would change the thermostat to this unit.
http://www.svtperformance.com/forum...ostat-cooling-system-reische-performance.html

I would do the coolant, drop the boost to 15 or less and do the thermostat along with a real temp gauge first. I have my temp sensor in a modified burp plug.
link -> http://www.svtperformance.com/forum...3/295546-brake-cooling-ducts.html#post3759584

BTW I'm using his brake cooling ducts as well.

 

[chrish900]

I am running a stock engine in OT, 412 rwhp. The only time I have cooling issues is when the air temp is 98 deg F or hotter and I am in the boost hard during OT. If I come out of the boost a little, then I can control the engine temp. High speed (OT up to 130 mph) without boost doesn't seem to raise the temp a whole lot for me. That would work on the autobahn. For OT, I will be boxing in the radiator this spring. I may also look for a hood with greater heat extraction. Question, would it help with air flow to install a mini belly pan from the lower air dam back to the front axle?

 

[racebronco2]

I have not seen or tested with or without a belly pan. My splitter goes to the k-member. I was concerned about blocking off the portion from the radiator support to the k-member. The new mustangs have a belly pan and they have vents in them. I have vents similar to the ones on my hood. My thought was there is alot of airflow underneath the car and our cars were not designed to have the underside of our cars blocked off like the vipers. The vipers do have huge heat extractors.

 

[camp upshur]

I agree with the Evans NPG and run it. It will prevent localized boiling, but a stock shortblock still has the tight piston-to-wall clearance which will always be a nag.

If you do run an Evans system you will not want to run a 'modified' stock style thermostat. Evans systems thankfully run Behr inline thermostats with a much smoother and sensical coolant routing and an external oil cooler. I would most strongly recommend as large of an external oil cooler as possible for extended high speed running. When you run boost the oil gets the heat.

One of your unfortunate problems will be that in Germany the fuel is so so much better (they use a Research Octane Number fuel..Super 100 RON equates to as USA RON/MON octane of about 95~96 I think). But to get the horsepower without detonation benefit of this gas you would have to advance and/or boost and then have to augment the cooling system to remove this heat. Something the drag racers or burst speed guys aren't as concerned with as an Autobahn cruiser. This fuel offers an EASY free 75-100-?? horsepower generation to any Cobra application, thereagain if you can manage the heat this combustion. Sure beats California 91 octane.

The thought of a clearanced shortblock and 95~96 octane pump gas and adequate cooling would allow you to run 17# or more sustained boost...the dream of every Cobra owner. That would be an Autobahn cruiser!

Jimmy it is very neat to read your posts again. A word of unsolicited advice: when you do switch to NPG, be certain to remove the block plug located behind the R/H motor mount. Yes it is a supreme pain in the butt and very easy to rationalize not doing, however, even after otherwise fully draining my engine I was very surprised to have QUARTS of coolant still in the lower R/H water jacket which was otherwise unknown and unrecoverable. It was enough to have nullified (through dilution) the NPG and all of its benefits.

So far as adding water to NPG, of course you can top it off with water and continue to run. Forever if one would like. It is just that the resultant NPG/water mix will not have the nucleate efficacy of NPG. It would just be coolant.

[ame="http://en.wikipedia.org/wiki/Nucleate_boiling"]Nucleate boiling - Wikipedia, the free encyclopedia[/ame]


Camp Upshur

 

[Fast GTO]

Anyone have any links of boxed in radiators.

Still considering the use of Meth for the Octane increase.

 

[wheelhopper]

I am a big advocate of running a good OT tune. Something that pulls some timing and adds fuel pressure compared to an optimized street tune. I loose 29rwhp with my OT tune compared to my street tune, but I can run for 30 minutes hard with no heating issues in 90 degree weather. It is probably not the best tune for gas milage as well. The only cooling mods I have is the "head cooling mod" and a 180 degree thermostat. Most Terminator guys are surprised to find I have a 2.8 upper and 2# lower and do not overheat.

 

[racebronco2]

Anyone have any links of boxed in radiators.

Still considering the use of Meth for the Octane increase.

There are many threads in this forum that deal with boxed in radiators.

I haven't seen any terminators running open track with more then 15lbs of boost in weather above 90*. I have seen one running about 17 lbs but 2 laps in and his car went into limp mode.

The cooling that needs to be done is not the iat2's but the engine temps. The lower the engine temps the lower the iat2's.

I have ran with 19* timing and a/f in the low 11's but couldn't tell the difference in engine temps, but it could be because i already have the cooling issue under control except when running in 105+* weather.

 

[Fast GTO]

Thanks, good info. My current setup is with a 2.2 KB running 17PSI. Looks like a larger radiator with NPG+ is the way go along with the 160 tstat (should NPG be ran with that tstat?). The meth should also help to prevent detonation int he combustion chamber as the water/meth will absorb excess heat (note this is different than cooling the air which it does poorly on a twin screw).

I've searched, but haven't found a thread with pictures of what people have done to box in the radiator...guess I suck at searching.

 

[racebronco2]

Here's one underneath the bumper cover.

As far as the sides go you will need to remove your bumper cover and either use thin aluminum, abs plastic or ??? I don't remember any pictures showing the sides blocked off.

 

[Jimmysidecarr]

cruiser!

Jimmy it is very neat to read your posts again. A word of unsolicited advice: when you do switch to NPG, be certain to remove the block plug located behind the R/H motor mount. Yes it is a supreme pain in the butt and very easy to rationalize not doing, however, even after otherwise fully draining my engine I was very surprised to have QUARTS of coolant still in the lower R/H water jacket which was otherwise unknown and unrecoverable. It was enough to have nullified (through dilution) the NPG and all of its benefits.


Camp Upshur

WOW! Ditto! Good to see you posting on here again!
Here's my plan Steve

Funds are very tight and since the transplant my need for speed has been adjusted.

I would like to retain the oil to water oil cooler if possible, since fun street driving will be the primary use of this car.

I am currently running an Evans/Behr stat and have not had seam failure. Per your recommendation I may just leave it alone. Obviously by pass is replumbed and stat located to upper hose.

I have been running through an empty factory t-stat hsng into the factory oil to water oil cooler.

My rad boxing is incomplete as of yet.

I'm running a 3.50" pulley on a 2.3 Whipple @ approx 13 pounds.

Thanks for reminding me about the right side block plug. I did know about it, but it is something NO ONE would want to forget about.

So far I have not puked 70/30 water/coolant yet, but I do back off to 100mph in 5th gear on the straights, typically about 3 laps from the end of the session, when I see the gauge climbing.

Steve do you think the NPG+ will transfer less BTUs to the point of piston to wall issues cropping up? Plugs indicate I've been detonation free on USA 93 octane w/ 10% Ethanol.

 

[Jimmysidecarr]

Thanks, good info. My current setup is with a 2.2 KB running 17PSI. Looks like a larger radiator with NPG+ is the way go along with the 160 tstat (should NPG be ran with that tstat?). The meth should also help to prevent detonation int he combustion chamber as the water/meth will absorb excess heat (note this is different than cooling the air which it does poorly on a twin screw).

I've searched, but haven't found a thread with pictures of what people have done to box in the radiator...guess I suck at searching.

Here is one example on an SN-95

P67387 Image Large Photo

Easiest way is to pull the front facia off and make cardboard and duct tape templates, then make sheet aluminum versions, or a light rigid plastic sheet.

Keep it light.

 

[PaleRider]

One of your unfortunate problems will be that in Germany the fuel is so so much better (they use a Research Octane Number fuel..Super 100 RON equates to as USA RON/MON octane of about 95~96 I think). But to get the horsepower without detonation benefit of this gas you would have to advance and/or boost and then have to augment the cooling system to remove this heat. Something the drag racers or burst speed guys aren't as concerned with as an Autobahn cruiser. This fuel offers an EASY free 75-100-?? horsepower generation to any Cobra application, thereagain if you can manage the heat this combustion.
Camp Upshur

Let me pop this bubble.
I found by an independent study done by Motec that the Shell Super 100 sold in Germany is just: 101.1 RON + 87.8 MON = 94.45 PON
So don't crank up the juice thinking you have a 95~96 playing field and run WOT on the Autobahn.

 

[Lumpydogs]

I am a big advocate of running a good OT tune. Something that pulls some timing and adds fuel pressure compared to an optimized street tune. I loose 29rwhp with my OT tune compared to my street tune, but I can run for 30 minutes hard with no heating issues in 90 degree weather. It is probably not the best tune for gas milage as well. The only cooling mods I have is the "head cooling mod" and a 180 degree thermostat. Most Terminator guys are surprised to find I have a 2.8 upper and 2# lower and do not overheat.

I agree. A rich tune is a cooler tune.

 

[03 DSG Snake]

Here's one underneath the bumper cover.

As far as the sides go you will need to remove your bumper cover and either use thin aluminum, abs plastic or ??? I don't remember any pictures showing the sides blocked off.

The stock setup has the sides of the Rad pretty well covered, is it not adequate?

Any benefit in doing the bottom only as in that pic?

 

[mu22stang]

The stock setup has the sides of the Rad pretty well covered, is it not adequate?

Any benefit in doing the bottom only as in that pic?

Air will take the path of least resistance. Go out to your Cobra and take a look at the unrestricted flow path for air once it passes through the opening in the heat exchanger cutout in the bumper. You can see straight through to the ground, in front of the heat exchanger. That same open space, when seen from the bottom, reveals the huge gap for all the air entering through both the radiator opening and heat exchanger opening to escape.

The idea is to get every ounce of air that goes through the radiator and heat exchanger openings in the bumper...through the radiator and the heat exchanger. The radiator has a partial box from the factory yes, but it could definitely be improved. Closing off the bottom and increasing the width and depth of the air dam, like in Carlos's picture, will make a big difference. Pull out the heat exchanger vents on the hood and she'll run cool as a cucumber (relatively), even on the track.

I've never understood why some go to a larger radiator and heat exchanger before doing the simpler, CHEAPER, and LIGHTER method of improving efficiency in the stock system first.

 

[racebronco2]

I think the reason why some of us get a bigger radiator and h/e is because some of us grew up in the 60's and 70's and it worked back then.

 

[mu22stang]

I think the reason why some of us get a bigger radiator and h/e is because some of us grew up in the 60's and 70's and it worked back then.

Carlos, the climate and intensity in which your Cobra is open tracked, judging by your knowledge, input, and pictures, could easily justify either of those modifications. My question is, with all the data logging information you've collected, what are your findings with those aftermaket units? Did you do them before, or after, extensive boxing of the bumper?

Because I'm going for a lean and mean, not to mention cheap, open track Cobra, I'm doing as little as possible to make this car perform. I feel that I will never need anything more than a well boxed bumper and a taller air dam to keep things cool. It will keep my front end lighter and my wallet heavier. My Cobra is stock sans an intake, exhaust, and tune, though and I will be racing primarily October to May.

 

[drudis]

Box in the ductwork on the way to the radiator, and FORCE all the air that comes in thru the radiator...

Works great for mowing the lawn too... (no mulching, just save it and take it to the pits). HAhahahaha...

 

[racebronco2]

Carlos, the climate and intensity in which your Cobra is open tracked, judging by your knowledge, input, and pictures, could easily justify either of those modifications. My question is, with all the data logging information you've collected, what are your findings with those aftermaket units? Did you do them before, or after, extensive boxing of the bumper?

Because I'm going for a lean and mean, not to mention cheap, open track Cobra, I'm doing as little as possible to make this car perform. I feel that I will never need anything more than a well boxed bumper and a taller air dam to keep things cool. It will keep my front end lighter and my wallet heavier. My Cobra is stock sans an intake, exhaust, and tune, though and I will be racing primarily October to May.

I wish i would have tried the hood mod before any of the cooling mods with the exception of the head cooling mod. Recently i tried to get a stock cobra to the track but it didn't work out, we were going to throw my hood on his car to do an actual back to back testing. I even went so far as to order a stock replacement radiator which was coming in a couple of days and i cancelled the order after waiting over a month. They kept telling me it would be in next week.

Like i have written before, all the cooling mods only allowed me to run longer before i went into limp mode (80*+ weather) .... the hood mod allowed my car to run cooler. Comparisons were with several of my friedns whom open track their cobra's.