[389SixPack]

I'm sure it been discussed and calculated, and someone out there has the answer. So, does someone already have chart of charge air density vs temp. I know the ATW CACs use ice water to drop temps. Where is the benefit start /stop point. 10º, 20º… 50º, 100º below ambient. I’m sure there is point of little gain. Has anyone done the math on this one and have a chart they can share?

 

[Charles]

It really never falls off. The lower the cooling media the more dense the intake air charge.

If you could cool the intake air down to -100 degrees of ambient it would be about the same as running 15lbs of boost non-intercooled as far as power and intake airflow without even having a turbocharger.

The cooler the better, no marginal benefit really. Dropping temperature is EXACTLY the same as increasing boost pressure, except that is does not have the negating side-effect that increased boost has of increasing temp and reducing the overall density. When you drop the temp the required airflow is instantly achieved by the atmosphere pushing to fill the void.

Dropping temp is a win, win no matter how far you push it. The only thing marginal is the required effort, complexity and price required to drop it every degree. That can make the cost outweigh the benefit. Which is why we have elaborate turbocharging systems, not elaborate nitrogen tanks to cool the intake air. Price and complexity.

15lbs of boost is easy relative to achieving -100 degrees intake air.

 

[389SixPack]

It really never falls off. The lower the cooling media the more dense the intake air charge.

If you could cool the intake air down to -100 degrees of ambient it would be about the same as running 15lbs of boost non-intercooled as far as power and intake airflow without even having a turbocharger.

The cooler the better, no marginal benefit really. Dropping temperature is EXACTLY the same as increasing boost pressure, except that is does not have the negating side-effect that increased boost has of increasing temp and reducing the overall density. When you drop the temp the required airflow is instantly achieved by the atmosphere pushing to fill the void.

Dropping temp is a win, win no matter how far you push it. The only thing marginal is the required effort, complexity and price required to drop it every degree. That can make the cost outweigh the benefit. Which is why we have elaborate turbocharging systems, not elaborate nitrogen tanks to cool the intake air. Price and complexity.

15lbs of boost is easy relative to achieving -100 degrees intake air.

Yep, that's is where I was getting to. At what point is the cooling system mute to other effects. Yes, I realize cooling effects keep going, and if cold enough start liquifying gasses out, but there is a point of diminishing returns of cooling versus boosting and the happy mix of both with reason of cost. I can easily see a GTA (gas to air) heat exchanger surface temperature dropping to -20 to -45 degrees F pre-CAC flow, but would need a trade study for the weight, cost and power versus adding more turbos, or both.

Just putting feelers out to see if someone here or in the past has been there, done that!!

 

[strokin_early_99]

I found a system that has a CO2 coil that goes in front of the Intercooler. Once you hit 10lb of boost it kicks on spraying CO2 gas into the intercooler fins essentially cooling the air as it passes through the cooler. Would this actually help or is just a gimmick?

Keep Strokin'

 

[THEDIESELMAN]

It would for sure cool the air down so it isn't just a gimmick.

 

[gregrob]

I've seen them on Subaru's around here. They don't do that much at all, they look cool, but don't do a lot.

Not to mention you have to figure out a way to keep the C02 from going into the air intake, it displaces oxygen so it would be like the opposite of nitrous.

One whiff into the engine would rob enough power to more than negate the effect of the cooling.

.02

 

[389SixPack]

I found a system that has a CO2 coil that goes in front of the Intercooler. Once you hit 10lb of boost it kicks on spraying CO2 gas into the intercooler fins essentially cooling the air as it passes through the cooler. Would this actually help or is just a gimmick?

Keep Strokin'

There are a number of sprays that could be used, and have been, and the cooling effect works but is short lived.

There are industrial cooling systems that will compress a gas, store as a liquid under pressure and when liquid released into coils, expands and transforms from liquid to gas, the vaporization temps are in the -60*F and some lower. The gas would then be re-compressed (typical refrigeration cycle) and stored (or continouos flowed). For the 1320 guys, they could cool during run and compress in the pits - no power lost during run. Other setups could be use in OTR where an EGT sensor could trigger the system on when a set point is reached.

Hey we could power it with an underbody turbo generator and extract some more power from the exhaust stream!!

Just thoughts of some toys to think about or play with.

 

[DarkShadowDiesel]

I found a system that has a CO2 coil that goes in front of the Intercooler. Once you hit 10lb of boost it kicks on spraying CO2 gas into the intercooler fins essentially cooling the air as it passes through the cooler. Would this actually help or is just a gimmick?

Keep Strokin'

some tuner on the speed channel was claiming that gave a 40-60whp gain on a 4banger but i don't know if i believe it. i don't know how effective that'd be.
your thoughts, charles?:gun:

 

[THEDIESELMAN]

Yep I saw that to it was on a 350z. On that show they kept using it while the car wasn't even moving just to show how cool it looked :lame:

 

[Charles]

Those things have to be used before you plan on making a high boost pull, otherwise the damn CO2 just goes right in the intake and cancels out the effect, or can actually LOSE power because of the oxegen depletion.

Most all of the guys claiming ANYTHING over 10 hp with an intercooler sprayer are spraying NO2 on the cooler. And yes......a WHOLE LOT of that goes straight in to the filter.

A study was done on this and using a long section of tubing actually pulling intake air from outside the dyno room for the engine, gains of around 8 to 10ish hp were found no matter if you were running CO2 or NO2. Put the filter back in the engine compartment......

CO2 would make maybe 2 or 3 additional hp or possibly lose power and NO2 would shoot up to 40 or 50ish.....

Weeeeeeiiiiiirrrrrddddd.......

 

[strokin_early_99]

By saying that it could rob power or get a whiff of CO2, I am assuming that you are referring to the CO2 getting sucked into the intake. On trucks running the AFE stage 2, would that still be an issue as it pulls air in from the outside and not from the engine compartment? However that would only matter if it was worth buying. And from the sounds of it, it is not worth the cost and cost to refill the CO2 for only 3ish ponies. I see why "Boogie Max" runs a air to water intercooler. It may cost some money to make but it don't cost anything to use.

Thanks for the edukasion,

 

[Charles]

Air:Water can give truly DIRTY results to intake air temp, egt and total airflow

Especially when ice hits the scene.

 

[DarkShadowDiesel]

by dirty you mean good or by dirty you mean it messes it up?

 

[Charles]

Good, lol.

 

[DarkShadowDiesel]

i mean, i figured, but i wasn't sure... you know just checking. you play with a lot of ricers!
:ford:

 

[389SixPack]

ATW with cooler tank, antifreeze water and dry ice is a potent mix for the 1320, but not a street workable solution.

Charlie, with the 47 thru the 38 thru cac at WOT, what kind of temps you seeing at the spider?

 

[Charles]

I have no idea. :aiwebs_001:

Right now I'm planing to swap to a softer spring in the gate on the 38R so that I can put more load on the 47 without overboosting the truck. As it sits I'm running about 10 or 11lbs on the 38 and about 22 on the 47. I would much rather see about 30 or 35 on the 47 and about 5lbs on the 38.

The truck's power/plant your ass is DIRECTLY related to the first stage boost gauge needle. You can just look at the first stage boost curve vs the engine power curve on the dyno to verify what the seat of my pants tells me everyday.

When the 47 is making 30lbs and manifold boost is at 50 with the 38 making 6 or so lbs, the durated exhaust gas temperature after a full run at full load in the high gears is 1250 to 1300 flat.

When the 47 is making about 22ish lbs and manifold boost is at 50ish with the 38 making around 10 or so...the exhaust gas temp same scenario sneaks up to 1600 by the time you're finishing off the speedo.

I would probe the temps, but I just don't have room for any more damn gauges. I hate gauges and I've got two on the pillar, one where the ESOTF goes for auto T-case guys one zip-tied to the antenna, and one servo taped to the dash near the pillar. Course I guess at this point, in the name of temporaryality, I could just tape on another, lol. But I already know that the coolest possible scenario is with the 47 making as much boost as it can without overboosting the manifold dependent on how much the 38 is making.

Not to mention that the hellacious jet engine audio starts to get wicked loud once the 47 starts up toward 25lbs or more. When it hits 30+ you might as well be sitting on the hood of a mod class truck just as the sled takes off behind it, lol.

I know it's supposed to be about function....but damnit, there's something to be said about striking fear deep into the pants of every 5.9 owner within hearing distance when you come up on boost.

 

[THEDIESELMAN]

Hell yeah I would love for my truck to sound like that so anything in hearing distance will fear me. I love the sound of a loud ass turbo, blower, supercharger it just makes me happy if you know what I mean.

 

[CSIPSD]

Throw this in... Water injection...

 

[389SixPack]

Throw this in... Water injection...

Yeah, got that already. And NOS lowers it too.

Lowering charge air temp increases air density of compressed air, thus increasing boost pressure. No internal drugs, just air. or you can raise boost pressure and try to hold at ambient - same thing. BUt if you raise boost - high - and super cool the charge, ya got a lot more O2 to burn. It becomes a trade between doing the high boost (double, triple turbos with there associated problems) or max boost from single and increasing charge density from cooling - or cost of one versus the cost of the other and which provides the gains desired with the least complications.

Was looking to see if someone had looked at these trades before and had some data to share. I guess I'll have to break out and dust off the old books, and do the math myself, and start laying out options to trade. Another project fot the list!!