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Engine Specific Info and Questions => IDI Engine => Topic started by: Gizmoman on August 04, 2013, 09:04:14 am
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Here is the plan for my Water to air intercooler. . .
(https://lh5.googleusercontent.com/-8ds1tNQK404/Uf55yaVRGlI/AAAAAAAACAs/ehZQ_-sIumo/s720/WESTY%2520INTERCOOLER.jpg)
The tank is one of those 1 quart cheap plastic jobs from the local FLAPS. I epoxied a 5/8 barb into it to feed the pump. What are your thoughts on using a "T" on the return (instead of going back to the tank)?
Any comments appreciated.
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I would want to have a second fitting on the tank in order to include the thermal mass of that coolant and reduce peak coolant temps. I also wonder which would return the lower temps, either running the laminova cores parallel vs. series counterflow to intake air. Possibly some testing once it's running would be in order.
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aaaahhhhhh no....
rember the discussion on the behind plate bottle?
you want a honda/gm style bottle/cap..
the water/air ic i have to play with on the vr6t has a honda style rad with cap on it... uses the "cheap" style tank you got.. as its just a succk from push to tank like behindthe plate...
that tank will crack/break with pressure... you would need to engineer a vw style bottle, ford/madza/dodge use them too that can hold pressure... for different shapes..
my jack rabbit came with a top waterneck adapter to fit one of the gm style caps to the system.. i would rig that to be the higest point of the system.. then you can use a bottle like you have.. its a monroso aftermarket casting on it.. but i cannot tell if its welded on to or not.. they mounted rad way low on jackrabbit.. how the purged the air out of the top hose..
you will be able to use the plate access too hell maybe t that bottle to feed them both for overflow?
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Thanks Libby, I was trying to get by without adding another fitting to the tank (which is under the back seat in the van) and is higher than everything related. It's only about a quart, so I didn't figure it could add much heat sink.
How hot should I expect? Based on what CRSMP5 is suggesting, I could have boiling water :o. If that's true I have to re-think the whole concept.
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I would want to have a second fitting on the tank in order to include the thermal mass of that coolant and reduce peak coolant temps. I also wonder which would return the lower temps, either running the laminova cores parallel vs. series counterflow to intake air. Possibly some testing once it's running would be in order.
IIRC, the laminova folks recommend parallel if possible.
Any idea how hot I should expect? I figured I would need to deal with 150 F or less - not boiling.
As for the thermal mass, I figure if the radiator/heat exchanger (with fan) can't remove the heat, all the volume in the world will eventually heat up. The tanks is just to insure there is no air in the system and it makes checking it easier. That said, the "T" might not let all the air out so going back to the tank would still be a good idea.
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At 20psi of boost I've seen pre-intercooler temps over 200°F.
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At 20psi of boost I've seen pre-intercooler temps over 200°F.
Hmm, I'm shooting for no more than 150 max - even still, that's higher than I thought.
Plastic tank is going to take a hit for sure. Darn, now I'll need to tig-weld an aluminum one and deal with high pressures as well :(
Here's the one I have now
(https://lh6.googleusercontent.com/-LkCEGiBUQjM/UeLYd2EsB9I/AAAAAAAAB-U/WjLGlmYDpDw/s640/DSC00575.JPG)
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These plastic fittings aint gonna cut it either
(https://lh4.googleusercontent.com/-ztUBrTVc_y0/UeLYbkYH7dI/AAAAAAAAB90/n0Ypne1OUE4/s640/DSC00571.JPG)
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theory.. same temp as antifreeze.. the big metal thing (the cooler is pretty stout that im playing with and all aluminum, so will catch all bay heat and asorb) is in the engine bay asorbing the same heat the coolent is.. expect is to run the same temp..
think of egt,s also and how they will heat soak a head and raise the temps in the head temps vs block temps....
what ever you do make sure no one can get burned... id rig in a vw coolent bottle.. put it in big square box with drain at bottom..
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theory.. same temp as antifreeze.. the big metal thing (the cooler is pretty stout that im playing with and all aluminum, so will catch all bay heat and asorb) is in the engine bay asorbing the same heat the coolent is.. expect is to run the same temp..
think of egt,s also and how they will heat soak a head and raise the temps in the head temps vs block temps....
what ever you do make sure no one can get burned... id rig in a vw coolent bottle.. put it in big square box with drain at bottom..
Just so were all clear - this system is not part of my water cooling system and is not connected to it in any way. The radiator in the diagram is a small unit (see photo above).
What I am trying to accomplish is to cool the hot compressed air from the turbo just before it enters the intake. I doubt it will ever get cooler than ambient but if I can bring it down from 150F to 90F that would be great.
I will add anti-freeze (pentofrost) but only to keep it from freezing. It should never boil or the radiator I have selected is way too small.
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intercooler is big chunk of aluminum mounted close to turbo..... the water to air one i have to play with weighs 2x as much as air to air...
air to air in open...
your is snuggled into the bay of a vanagon... it in its self is a heatsink... thiunk of the heat level you get out from under the cover after a spirited drive..
so yes i woul d100% think it will need to cool effectivily to cool its inner gas vs the surrounding air of the bay... but the bay will effect its overall temp too..
2nd thing to rember.. your only under boost at speed.. so the little fans only need to work in stopped traffic to help keep it to those temos.. cause if you honestly think that little fan will help at 65mph.. i cannot see it.. air flow will be much more then it can make..
id honestly think of it as its own cooling system... but with your set up to add a 2nd rad is easy..how the watercooled stuff helps most.. couple small rads easy to add in vs 1 big one..
and yes i know its a 2nd system.. i am trying to decide how to do the rad fan, water fan set up as this rad = ac condensor in size.. so fits the roddo rad like a ac condensor on a mk2 would.. all i gotta do is cut a nice hole in the core support for its cap.. and small overflow off to the side..
so me i have this front air mass to cool it.. but ok.. fan.. if rad one on i twill draw thru the cooler too.. but the fan will blow the hot air on the cooler too.. :( easy fix with a duct.. but no way the fan can do better cooling then direct air..
the rad will transfer heat to the cooler rad... much like ac does to coolent system..
cars with ac vs non ac.. load vs no load.. vs temps around town and on road.. that intercooler will be antifreeze temp at min on a hot day... so expect it to boil.. brass.. good bottles so on.. this kit i have came with a honda style cap... real pia to get on/off.. but that tells me to expect normal cooling system function.. just when really cool out i bet it runs alot better then a hot day..
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Thanks CRSMP5, I get what you are saying - basically that I should expect temps of the IC water to be close to or the same as the water in the engine.
Here's my IC. . .
(https://lh6.googleusercontent.com/-ADjrpB7K82w/Uf65xW4SUcI/AAAAAAAACBE/hSr6re5EIrI/s640/DSC00275.JPG)
(https://lh4.googleusercontent.com/-lnY4FsqCCAU/Uan70oIUSPI/AAAAAAAABvg/QayUuVX08-I/s640/DSC00476.JPG)
The two cores are 90% in the air flow and not touching the aluminum as they are centered by the o-rings once the caps are on.
The only thing that will cause them to heat up will be the compressor air (I don't know how hot that could get). According to Libby, it could be as high as 200F. I will be running 15 psi of boost so I doubt they will go much higher than 200.
The water runs through the center and also the small holes around the OD of the cores. Air is forced through gazillions of fins on the core OD. This is done through two very close fitting tubes inside the housing which have in/out slots their entire length - the cores fit inside these tubes. I have blocked off all other flow paths and the air must pass through the fins.
I guess if there were no water running through it, sure it would get as hot as everything else in the engine bay. I just don't see how it could ever get to boiling temps unless the pump failed (which it could I suppose). If the pump and small radiator fan is running all the time It seems I should be able to keep the temps down easily.
If the water gets to boiling point (212F), then the whole concept isn't working at all because that's what the air would be as well.
I'm no thermo-dynamics engineer but boiling water in a WAIC doesn't sound right.
I will also be monitoring post IC temps with a temp probe when if I get it running. ;D
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well my worry time for you...
go into grocery store on a 90*f day... in there 20 min... ho much heat has soaked into the parts in the bay as it sits there with no airflow..
when you restart it.. it will have to cool off that heat soak.. i garentee.. it will be at fan shut off coolent temp... hell im thinking audi design, timmer and all for the pump for it to keep both cooling systems pumping coolent after shut off for 5-10 min... hell maybe wire in the goofy sensor like a 88ish golf with temp probe in the injector area of gasser in you area between head and ic you made so the fans and pumps cycle till the actual ambient temp around the head cools down..
for mine im going to add in a 2nd rad fan switch to the awic set up so when either gets to 82*c the main fan kicks in.. using a pusher fan on the awic imo waste and honestly i want it to warm up to a "set temp" per say too.. having its fan run as the engine runs would be silly on cold days and imo hard to keep it in tune too..
so yes... plan for it to get hot.. no reason to burn anyone.. do it right with ideas of growth.. not damb i may have to reingeneer that... till you get it going you will not know its temps... but no way heat soak will not be a issue for your project.. i am worrieed bout that in light weight vr6t car...
next.. my kubvan, towing jack rabbit this past madness... it needs a real oil cooler on a 75*f day.. no way im at 4000lbs and had issue of oil/water temps.. egts were 950ish.. but oilwill heat up the stock oill cooler enough to heat the antifreeze and then neither cool right.. a 30 min stop would net me 45-55 min of drive time til the antifreeze would rebuild to boiing and not cool any more... these hills nothing vs out west and had no issue on 35-55f days... just that 20*f in ambiet temps is enough to crew with heat soak.. and far less load via wight vs cali.. jackrabbit stripped now vs then and kubvan not near as full of crap..
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well my worry time for you...
No need to worry for me - That's why I posted the question and I do appreciate your view - it does make sense with the closed up bay sitting in the 100F parking lot after a quick run.
I'll build a tank/system that can hold the pressure of boiling water. But I still hope when I'm heading down the road, all this work will net intake air temps well below what they were without it.
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compressed air via turbo.. less temps then without it... it was still more then antifreeze levels before it was added or even created.. its whole goal is to drop the charged pressure air temp much like ac... so yes no matter what it will help lots... just think you overlooked at the temps it operates...
if egt 1200*f.. whats the charge air? i bet 200-600*f..
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Do any of you "turbo specialists" know what charge temps I should expect from a stock K14 running at 15-18 PSI would be?
The engine is an AAZ and the pump is from Giles built to provide up to 150 HP IIRC.
Libby says he's seen 200F+ @ 20 psi and CRSMP5 says it could go as high as 600F.
Reason I ask is I may need a larger radiator for my WAIC or I may add water injection to cool things down. I'd really like to get this right the first time.
I've searched on GOOGLE for a chart or any basic info - no luck.
Any help appreciated.
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Depending on how heat soaked everything is I could see it range from ambient temp to probably 300f at the hottest point. 200f is what libby sees so I would say that is accurate as there is no need to doubt him. But that would be full pressure, as soon as you let it down some the intake charge would come down so it isn't like you would have to cool 200f every running second. My K24 could burn your hand pre IC if you touched the pipes after hard running. It was cool to the touch on the post IC side at the same time.
Most awic setups are for 250+hp gas engines, so what ever rad you have is probably fine. There is no such thing as under kill so I like to over kill everything, and you could get a huge rad. It won't hurt, but if you are already using a rad designed for a 250hp gas engine it is already 100hp overkill.
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BTW I wouldn't T it. This could solve all your issues by running it into the tank as others have said. Then the bigger the tank you have the less temp change you have and it is harder to keep cooling the same water over and over. If you had 2 gallon tank it would be easier to keep the quart continually cool and use the other to help cool the small amount. Your system may hold close to 3 gallons with a 2 gallon tank but the coolant won't heat soak so bad and turn it into a heater like you are worried about. Also, I run Redline's water wetter in most things I worry about cooling. It really does work to help the heat transfer. In my off road only Ford I see 30F difference in coolant temps. It is compatible with all antifreeze that I have seen. You could add some of it and try it if you don't think it is working properly. Basically it pulls the heat out of the coolant better but even more than that it pulls the heat out of the rad to get it to cool it better. Just some of my .02
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ave no idea what to assume the intake temp charge is... but i can beleive 200-600 is possible via red hot turbo vids... when the hot side glows red no way the cold side is cold...
egt 1200f.. id say max heat transfer via heat soak is 50% at worst which is why i say 600f could be possible... where my number comes from...
now how can intake temps getthere.. intake ports between exhaust ports on head.. if they pushing 1200f out.. they on both sides of intake ports.. that heat transfers too...
so head port, ic gas temps, turbine out temps is all voodoo... no one i know of has gauged such readings to know... so i build for worst case...
do the rad you have for now.. its voodoo.. gotta play to test.. you look to have things monitored.. use thoise gauges.. test..
with oil temp, egt, water temp, boost and your waic temp gauge you should be able to tell thermal overload.. honestly you will see the oil pressure to get a little wanky when you start to reach it.. then paying attention to the other readings, heat so on.. you can see when your at it..
if you see the need for more.. add a 2nd rad in line with the 1st one... put it in the middle.. audi 5000 td had a 2nd smaller rad between grill and timming belt for the added little it needed..
you lack ac right?? get custom rad to fit where ac condensor would go.. those are huge on a vanagon.. so use what you have.. test.. you have room to grow..
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Thanks Theman and CRSMP5 - all good info. Just for the record, I'd never doubt Libby - he just didn't seem 100% confident in his statement. I was looking for some numbers but there doesn't appear to be any - so it's still a bit of "voo-doo" as CRSMP5 suggested.
For some reason, I don't have a lot of room at the front radiator even though I don't have AC. I remember a post from either Libby or Synchronicity that mentioned making a water tank from 55 gal plastic drum ends (can't find the link right now) that replaces the spare under the front end. I may go this route for a huge water tank as my tall tires are now too big to fit in that spot ;D.
I'll keep you posted. As usual, it's slow going as I mostly only work on it weekends.
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voodoo it is... but my voodoo comes with 23000 miles of my box and what im noticing at 4000lbs of weight.. for a few thousand (4-5k) of them miles.. i have 02a gearing and all vs the vanagon buzzbox..
its only why i can say over do the cooling.. imo on a 80*f day pulling a 800ish pound shell at 70ish mph with hills.. say 2 people.. camping ccrap id say close to 4000lbs total.. vs a 40*f day at 80mph with a easy 500-1000lbs more weight.. the 80*f day could kill the toaster... i know how to read my instrumentation though... saved me with the oil usage n 6400mile trip.. and kept me from cooking it the other weekend... and that was pure ambient temp vs load... way to madness no thermal issues like this.. but 60*f is alot cooler temp..
but i also have many miles under the belt of its normal 2600ish weight.. so knew where my normals are.. for me to get to thermal issues... = 3 digits mph.. big long hills.. and 1200f on egt.. for miles when i say long... hell 140 gal of bio in the back in drums no issue... on 70*f days.. but 4000lbs seems to be the number it does not like on a 75*f day... vanagon camper close to that... and you want to drive in warm weather..
for me to tow the jackrabbit around as a real running car.. oil cooler and bigger rad are planned now.. but i got room for that growth.. square box makes it easy..
i know diesel rads different vs the gas counterparts int he vanagon.. wonder if they are different in size.. how i know different is the bleeder diesels have is like a brake bleeder vs the gasser bolt/washer set up.. have to hit libby on that...
i too agree with libby knowledge.. expecialy since he likes vanagons.. i do not.. :P
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voodoo it is... but my voodoo comes with 23000 miles of my box and what im noticing at 4000lbs of weight.. for a few thousand (4-5k) of them miles.. i have 02a gearing and all vs the vanagon buzzbox..
its only why i can say over do the cooling.. imo on a 80*f day pulling a 800ish pound shell at 70ish mph with hills.. say 2 people.. camping ccrap id say close to 4000lbs total.. vs a 40*f day at 80mph with a easy 500-1000lbs more weight.. the 80*f day could kill the toaster... i know how to read my instrumentation though... saved me with the oil usage n 6400mile trip.. and kept me from cooking it the other weekend... and that was pure ambient temp vs load... way to madness no thermal issues like this.. but 60*f is alot cooler temp..
but i also have many miles under the belt of its normal 2600ish weight.. so knew where my normals are.. for me to get to thermal issues... = 3 digits mph.. big long hills.. and 1200f on egt.. for miles when i say long... hell 140 gal of bio in the back in drums no issue... on 70*f days.. but 4000lbs seems to be the number it does not like on a 75*f day... vanagon camper close to that... and you want to drive in warm weather..
for me to tow the jackrabbit around as a real running car.. oil cooler and bigger rad are planned now.. but i got room for that growth.. square box makes it easy..
i know diesel rads different vs the gas counterparts int he vanagon.. wonder if they are different in size.. how i know different is the bleeder diesels have is like a brake bleeder vs the gasser bolt/washer set up.. have to hit libby on that...
i too agree with libby knowledge.. expecialy since he likes vanagons.. i do not.. :P
OKOKOK - I get it dude, really, I get it.
I'm putting a high temp system in and you not liking vanagons is fine, I agree, you shouldn't get, drive, fix, ride or camp in one. But I still appreciate your answers ;)
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My previous comment was based on some testing I did a while back with temp sensors both pre-intercooler and post-intercooler. The temperature would change fairly rapidly with changes in boost pressure. There also was a fair amount of hysteresis to the temperature probes, boost tubing, etc... The highest pre-intercooler temps I saw were around 225° on extended grades pushing 20psi or so while driving at 7,000ft elevation.
Temperature Rise = (ambient Absolute temp)[({outlet Absolute pressure/inlet Absolute pressure}^0.286)-1]/compressor efficiency
Lets say ambient temp is 80°F(300°K) and that boost pressure is 14.7 psi at sea level (14.7 + 14.7). For convenience, lets assume inlet pressure is atmospheric although the air filter will cause a bit of a drop. For convenience lets also assume a compressor efficiency of 75%.
Temperature Rise°K = 300[({29.4/14.7}^0.286)-1]/0.75 = 88°K
300°K + 88°K = 388°K = 239°F
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Crs has nightmares about his whole lot of cars being mysteriously turned into vanagons and audis. ;)
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My previous comment was based on some testing I did a while back with temp sensors both pre-intercooler and post-intercooler. The temperature would change fairly rapidly with changes in boost pressure. There also was a fair amount of hysteresis to the temperature probes, boost tubing, etc... The highest pre-intercooler temps I saw were around 225° on extended grades pushing 20psi or so while driving at 7,000ft elevation.
Temperature Rise = (ambient Absolute temp)[({outlet Absolute pressure/inlet Absolute pressure}^0.286)-1]/compressor efficiency
Lets say ambient temp is 80°F(300°K) and that boost pressure is 14.7 psi at sea level (14.7 + 14.7). For convenience, lets assume inlet pressure is atmospheric although the air filter will cause a bit of a drop. For convenience lets also assume a compressor efficiency of 75%.
Temperature Rise°K = 300[({29.4/14.7}^0.286)-1]/0.75 = 88°K
300°K + 88°K = 388°K = 239°F
Now that's some great info right there, thank you libby. I sent a PM to Synchronicity regarding his 7 gallon spare tire tank he made. That should be a good heat sink ;D
Crs has nightmares about his whole lot of cars being mysteriously turned into vanagons and audis. ;)
I do appreciate his point on heat soak but that is still funney ;D
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I ditched it... it leaked too much. The lid just wouldn't seal. If we could find a one-piece tank for that location with a similar shape, that would be nice. Even without the reservoir, the system holds just over 2 gallons of coolant, using 5/8" hose. If I decide I need a reservoir for it, I'm going with a section of 4" PVC pipe instead, probably in the return line under the van. Right now, I don't seem to need it.
My chargecooler is always cool to the touch in the engine compt. when running, but it does warm up when the van sits after. Try to add an insulation blanket between the turbo & intake if you have room, and/or use a turbo hotside heat cover.
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For what it's worth, there is no reason to bother making the AWIC a sealed system. It is only soaking up turbo heat when you are under boost, which is really only a small percentage of the total time.
I run mine with a small vent hole in the lid of my tank. I do loose a little tiny bit to evaporation but I'm talking like a 1/4 cup every few months.
In terms of fluid temperature, I would definitely agree with CRSMP5 in that the AWIC coolant will soak up engine bay heat when you are stopped. If you come off the highway, stop and pop the hood the boost pipes will be cold, after sitting for 10 mins they are hot to the touch just like everything else under the hood. Same goes for the AWIC. With my system it doesn't seem to matter though, as soon as either the rad fan is on or the car is moving the heat is gone from the AWIC system pretty quick. The hottest temperatures I have ever seen in my AWIC burp tank are after the car has been sitting shut off for a while.
I definitely don't see temperatures anywhere near boiling in my AWIC coolant. The air exiting the turbo is definitely that hot but heat transfer goes from hot things to cool things - it is not necessary to heat the coolant up to boiling temperature in order to cool the charge air down, in fact quite the opposite. The hottest AWIC core exit temperatures I've seen on my system under normal conditions have been about 15-25°C above ambient, though I can only check that by driving hard then jumping out and opening the hood to see the thermometer in my tank so the actual "under boost" reading is probably higher.
My AWIC radiator is about double the size of the one in the pictures here so YMMV. I went with a monster one because I could make it fit - the only penalty to running an oversized AWIC is the extra weight of the water / components. Really though we are only talking about a few pounds so nothing worth worrying about unless you have a race car.
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All great info!
As I said earlier, I'm no thermal Engineer but it seems obvious that the size of the tank is somewhat a non-issue. Just like the stock overflow tank on the hot engine (very small), if the rad can't cool the liquid, I'm fighting a loosing battle anyway. In other words, adding more liquid to an undersized system just buys more time as it will all eventually get too hot as well - again, if the rad can't keep up. The size of my radiator may be too small for the task, and I'll have to see on that. Adding a large tank is not really going to help on a long 6-8 hour trip.
BTW, I have no idea how much "continuous" boost I will need pushing the bread-box through the wind at 65-70 MPH, but before it went South, 10 PSI was the norm. Even slight hills put me to the 15 psi mark (max boost adjusted by the DIY controller).
I expect fours driving at 10 PSI, stopping to let the wife do her thing while I get diesel, heat soak will be an issue as I get going again. A few minutes of fan over rad should bring things back in line - that is if the rads not too small to begin with.
Now I have and EGT sensor (DUH), a Giles pump and a WAIC, things may change a bit but I want to design towards a worst-case scenario to minimise the tow charges ;D ;D
Again, many thanks to all - I'll keep you posted (albeit slowly).
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The temperature of the charge air varies dramatically and very quickly. Having a higher coolant volume will reduce peak temps, especially if your radiator doesn't always cool the coolant down to ambient during peak loads.
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The temperature of the charge air varies dramatically and very quickly. Having a higher coolant volume will reduce peak temps, especially if your radiator doesn't always cool the coolant down to ambient during peak loads.
Hmmm, peak loads - good pointy libby
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For stand-still heat soak, you could always add a timed relay and/or temp sensor to keep the water pump running for a while after shutdown.
That would affect battery life, though, if over used.
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honestyly.. he needs 2 systems..
he needs a cool down fan built into the rear vent by windows to suck air up thru them when shut off.. couple bigger cpu fans would i bet do wonders... they 5v.. so id say a neet but unknown result idea.. but crap bet it would have little batt life impact.. those odd solar panel kinds runnning off a temp probe would be really tits.. they using those on car window parking lot applications...
vw used the temp probe method on cis cars from 85 up... after run till the area between head/manifold a certain temp to help prevent the cis fuel lines from boiling fuel.. so he can retro fit that i bet as vw wiring simple in that era..
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If I would add anything to run after shutdown, it would be an oil pump moving oil through the turbo.
As for the WAIC, I'm gonna treat it like a regular cooling system. One small tank with a pressure cap venting to another small expansion tank.
Thanks for the consideration though - gives me the warm fuzzies ;D
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If you run the same type of coolant in your engine and your AWIC system they could share the license plate door burp tank.
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One big reason to keep them separate is everything in the AWIC is aluminium or nonmetallic. If you mix with engine coolant you have to worry about all kinds of galvanic stuff that you will never see in a "single metal" system. My AWIC coolant stays hella clean as a result.
Sent from my HTC One X using Tapatalk 2
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If you run the same type of coolant in your engine and your AWIC system they could share the license plate door burp tank.
I bought enough pentofrost to do both systems easily.
Thanks vanbcguy - and you are correct, the WAIC system is all aluminum, but libby's suggestion is certainly worth consideration. If this very expensive Pentofrost still creates crud (due to the iron block) I'll be very disappointed.
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I really don't think heat soaking will be a big deal. Yes, the water in the WAIC will get to engine compartment temp, but as soon as the system kicks on, it'll cool the system. The WAIC won't care if the warm water came from engine compartment heat or heat from charge compression.
After sitting for a while, by the time you're at the point where you need max power, you should be a-ok.
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I really don't think heat soaking will be a big deal. Yes, the water in the WAIC will get to engine compartment temp, but as soon as the system kicks on, it'll cool the system. The WAIC won't care if the warm water came from engine compartment heat or heat from charge compression.
After sitting for a while, by the time you're at the point where you need max power, you should be a-ok.
As you can see by the diagram at the start of this thread, I have no provision for boiling hot water. The concerns of many here is that it could boil under "heat-soak". Thinking of it that way, it does seem that fluid volume may be a simple solution as I doubt the heat soak could boil several gallons of water.
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I think of it this way; I have never had the underhood temps hotter after I shut the engine off than before. If my water temps don't get hotter than 200(ish) F, then I don't see how anything else under the hood will get hotter either.
Add to that your intention of adding rad coolant to the mix, and run a pressurized system, (both which raise the boiling point of water), my opinion is that boiling is an issue you won't have to deal with.
On the other hand, I don't have any experience with WAIC systems, so there may be aspects of this that don't jive with my theory.
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I understand your idea of the never hotter after I shut it off, but for the first couple minutes it is. All the oil and coolant that was cooling and circulating isn't anymore, the engine becomes a hotspot and it radiates heat out of it. The engine will heat soak the oil, and coolant and everything around it. My engine mount in the rear gets hot even*steel homemade one for low mounted vnt on mkii* but it shouldn't be boiling too badly or hard. I try to let things idle down for at least 30 seconds before just turning it off to help equalize the heat and not add anymore than idle combustion makes. When my EGT gets down to 200-250f then I figure it is ok to shut it down.
Run Water wetter from redline and you will probably never have an issue.
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My Cummins idles in the high 200's/low 300's. I have a turbo timer that keeps it running after shutdown until EGT's get below 400f.
I agree there will be hotspots but I suspect they'll cool before water in a WAIC starts to boil.
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I would not recommend running straight water in the AWIC system anyhow. Hardly as effective as a glycerin mixture, and more prone to freezing/boiling. I'd run a 70/30 coolant mixture as you would in the radiator cooling system..
It is an aluminum cooling system all the same.
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I agree.... straight water is asking for trouble. The coolant is anti boil, anti freeze, anti corrosion and a pump lubricant, all in one plastic bottle.
Having never heard of a WAIC before, it sounds like a great idea...especially for tight applications.
Designing one that actually works might be fun.
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As I mentioned, there's going to be Pentofrost mix in there - same as the engine. Never intended to run straight water. What water there is, will be also distilled.
Not running an expansion tank will save some hassle for sure. Water (with antifreeze) transfers heat real quick. In other words whatever heat the engine puts into it, it will put it into all of it (if that makes sense). Another way to look at it - there's not going to be some hot water and some cool water unless I had a valve in the system which I don't. Don't know what the total volume will be but it's probably around three gallons with the current tank, hoses, rad, etc.
I was a welder in my ute, and I figure if the entire block were 500 F. and I stuck it in three gallons of water, It would sizzle a bit but the water would never boil ;D
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I understood you know the value of coolant but there are those that believe straight water is the best way to go...and they'd be wrong for the vast majority of circumstances. Perhaps, straight water may be more benificial in some way I can't imagine, but, well...I can't imagine how.
I'm really digging this idea.