Old a/c cooling discussions

[Mayhem_J30]

You guys remember when we used to talk about some how using the stock A/C system to cool the intake air or even an intercooler? (this might be old news by now) But SVT has done it.http://www.autoweek.com/cat_co...33474

[maxnix]

Yeah, I remember Q45tech said Ford had a patent on this technology.

[Q45tech]

50 HP for $750 [factory quanity price][after they've already spent $5,000 supercharging it] sounds like a deal to me. The only thing that comes close is the JWT ecu [25-30 HP for $600].

Members forget that each 11F is a 1% in air density change and a 1% lowering of power output.. Air that airrives just before the injectors has been heated by 40-50-60F passing from the front of car thru intake system.........necessary in cold weather to help vaporize the gasoline [avoid puddles in the head runner floors].

Nice to see they were explaining that much [some] of the Nitrous gain comes from charge cooling the 80-90% of the air it is mixed with after evaporation [ even 25% of minus 140F is 35F cooler charge].

[Mayhem_J30]

50 HP for $750 [factory quanity price][after they've already spent $5,000 supercharging it] sounds like a deal to me. The only thing that comes close is the JWT ecu [25-30 HP for $600].

Members forget that each 11F is a 1% in air density change and a 1% lowering of power output.. Air that airrives just before the injectors has been heated by 40-50-60F passing from the front of car thru intake system.........necessary in cold weather to help vaporize the gasoline [avoid puddles in the head runner floors].

Nice to see they were explaining that much [some] of the Nitrous gain comes from charge cooling the 80-90% of the air it is mixed with after evaporation [ even 25% of minus 140F is 35F cooler charge].

Yeah, they did give the best description I've read so far. Motortrend did a small writeup on it, but never gave details. Sounds like a good idea by cooling anti-freeze with it. I already fortell Lightning owners moding their A/C to give 110% power to the cooler system.

[Eswift]

looks just like a production car way of putting ice water in the reservoir for a liquid to air intercooler. both right around 30F. any liquid to air intercooler could be converted very easily to accept the chilled glycol.

[Eswift]

50 HP for $750 [factory quanity price][after they've already spent $5,000 supercharging it] sounds like a deal to me.

i think an aquamist water (even some methanol) injection system (about the same cost) would yield just as impressive results, and doesnt require messing with the AC system. You would, however, need to fill up the washer fluid tank roughly every time you got gas. (assuming a 10% flowrate compared to the fuel)

Its been used on all of the WRC cars for several years with immense success, some production cars Iin europe) even have it integrated as a factory system.

[Q45tech]

The problem with misting is it displaces the air [10% water means 10% less air to burn.......sure it lowers the combustion temperature and stops detonation [requires more timing advance to compensate].

It is all a careful balance: 11F lower means 1% denser.

Most bad things happen in summer when the air is 100F and intercooler are not efficient unless as large as the front of car and the air can never get below 130-150F with chilled water you can get down to 40F vs misting non chilled water maybe 80-90F.................4-5% more power is significant for the AC chilled water to air intercooler.

Each 1.0 psi of boost raises the outlet air temp by 12-15F.......8psi is 100-120F hotter at minimum...........

Water/ethanol was used on Oldsmobile Jetfire in 1962-1963 a turbo 215 ci [3.5 liter] V8...........the owners kept forgetting to fill the water tank every other day.http://homepage.sunrise.ch/hom....htmlh ... ps....html

[Eswift]

wow dennis, never heard of the jetfire...guess you learn something every day. sometimes its in class, sometimes its on nico.

if you combine the increase in charge air density ( as well as a slight temperature drop) of the front mounted air/air intercooler with the water injection, results would be comparable with the AC chilled air/water cooler. surely, The anti-detonation qualities are very inticing.

An efficient supercharger can easily be set up to provide an excess of CFM for a 8-11 psi appliaction on a 3 litre engine, so air displacement is a factor that can be tolerated, in my opinion, especially for the increased longievity imparted.

[Q45tech]

But every extra psi is 10-15F hotter air you must waste energy to cool. SO very wasteful to overboost then try and over cool.The best performing engine [the one that will last the longest]would be the one with the lowest boost and coldest air and least amount of timing advance.Ideally one would use water/ethanol and nitrous [small tiny shot say 25-50 HP] to make sure that the intake valve and the air passing the injector going into the valve was 40-45-50F even in 110F ambient conditions.............almost impossible to accomplish..........without some thought.

[Eswift]

i wasnt saying to actually use the extra CFM to produce an excessive psi, just that available psi on that engine from a supercharger is not the limiting factor.

clearly, the desired injection amount is directly related to the tolerance of the engine to the extra non-combustibles and the lowest charge air temp. possible,

the best method of tuning i see would be to turn up boost until detonation, introduce water injection, turn boost up againuntil detonation is reached, increase water injetion....etc and so forth until water injection rate is maybe 80% maximum.

in this last round, the timing should be backed off enough to provide a decent blanket of safety.

since all of this tuning was being performed on a dyno, the HP yields at every variation will be known, and if the final situation is not the optimal, the settings can be changed accordingly and can be approached by successive approximation.

unfortunately, the addition of nitrous to the equation leads to packaging and refilling problems....not daily driver material, thats for sure.

clearly, none of this tuning will increase the longeivity of the engine, but thats not the (immediate goal). lowest boost, coldest air, and least amount of timing hike = the stock engine, so of course only reliability losses are really to be had.