Intake Precooler for Forced Induction

[Stealer Of Souls]

Has anyone done this?
For a forced induction car tried like a dry ice box on the intake?
If a turbo (in very simple terms) basically multiplies the heat content of the air it's ingesting then dropping the intake a few degrees results in many more degrees cooler at the output.
Which I guess would mean that the intercooler (aftercooler) would be "more" effective.
Or you could use a smaller cooler.
Or you could dial up the boost a bit more.

Anyways. Thoughts? Other than practicality that is. Just another thought in the pipeline...

[Dr-X]

I've heard of WAIC's using ice cooled water. I've always wondered about using peltier coolers, like on the plenum or whatever, but I think a lot of the time, you'd be using more power than gaining. I've heard all sorts of stupid ideas, like using air conditioned air for the intake charge, etc.

[Rollux]

If the air entering the turbo is significantly cooler than ambient, and you have a nice efficient turbo, your intercooler could become an interwarmer, or pointless. Would be easier to just place your air intake in the coolest spot possible, and make your intercooling method as efficient as possible

[Chickenman]

One of the most promising Ideas I've seen is the CO2 intercooler rings, a few squirts and you got cold I/C. The pipes are in constant contact with the I/C as well... *goes to find where I saw it*

[Scotty]

One of the most promising Ideas I've seen is the CO2 intercooler rings, a few squirts and you got cold I/C. The pipes are in constant contact with the I/C as well... *goes to find where I saw it*

It is in speed mag there is also one fuel-cooling block, which I do not understand. There is also an article on the sealed barrel intercooler that is plumed into the radiator.

[Dr-X]

Plumbing an IC into the radiator would warm the air up, significantly.

If the air entering the turbo is significantly cooler than ambient, and you have a nice efficient turbo, your intercooler could become an interwarmer, or pointless

The air heats up siginificantly when compressed, so even if air entering the compressor was cooler than ambient, it would come out of the turbo much hotter. The intercooler would still have room to cool it.

Remember that the best air temperature isnt the lowest air temperature. Optimal air temp for optimal atomisation of fuel is in fact higher than ambient temperature, though I cant remember the exact figure.

I've seen cars injecting nitrous onto the intercooler to cool it, which resulted in a significant gain in HP. It was later discovered the nitrous was quickly evapourating and making it's way into the pod filter

[Monsterbishi]

One of the most promising Ideas I've seen is the CO2 intercooler rings, a few squirts and you got cold I/C. The pipes are in constant contact with the I/C as well... *goes to find where I saw it*

Only problem is the waste co2 gas then gets sucked into the motor...

imho, Water/Meth sprayers have worked the best for our car, it's like liquid ice...

[CozmoNz]

the system with c02 i saw had the 3 systems.

the CAI system, which had a teardrop in the middle of your intake piping. running cold co2 through it caused the air around it to be dramatically cooled, probbaly best put just infront of the throttle butterfly.

the second was a fuel block, cool fuel = more dense... same system as air.

more fuel + more air = more power. simple principle.

and cold fuel cant be worse than hot fuel at all .

the last being the c02 spray, which as said, could get sucked up after being sprayed over the intercooler.

so i say skip the c02 spray, get water injection .

[Stealer Of Souls]

I've investigated peltiers. Basically they'd only be useful as a pre-run cooling during drag races or time trials. Not much use as a continually running system. Too much power draw...

As for the iced water WAIC that's not exactly new. I'm more interested in any potential benefits of cooling the air before it enters the turbo. 1 degree at intake might be worth as much as 5 or 6 degrees at output. So if you could halve the intake temp (say drop by 10 degrees) then you could potentially halve the output, or by as much as 50-60 degrees! Coupled with a nice ice WAIC might make a mighty drag/dyno/time trial beast with intake temps below ambient!

[Monsterbishi]

CosmoNZ has a good point that so many people neglect to think about when building their fuel systems, fuel temps affect horsepower in a significant fashion, very much in the opposite way that water injection does.

Hottest I've ever felt was a guy running a high-pressure intank pump, freeflowing into a surge tank, which was feeding another high pressure pump, by the time the fuel had run through the system, the surge tank was literally too hot to touch!

[vvega]

Hottest I've ever felt was a guy running a high-pressure intank pump, freeflowing into a surge tank, which was feeding another high pressure pump, by the time the fuel had run through the system, the surge tank was literally too hot to touch!

and thats why that guy has no idea
typically you use a high volume pump to move fuel into the swirl pot
the you have a high pressure pump to the rail
then this feeds back inot the tank

a good fuel system is one that is well designed and though about there has also been disccustions on this here before
please use the shearch and go have a look you may find it helpful

oh and just for the record 5 dgrees drop at the intake might drop you 1 degree at the outlet of the turbothe heat is made buy the pressure that is been held in the intake
more pressure = more resistance
and we all know that resistance generates heat

meh im tired cbf


vt

[Scotty]

Here are scans of the article There are 3 pages total about 1meg.

[kingcorolla]

just another thing, on the fuel system.

Im sure fuel (like intake air) has an optimal running temp. Icey cold fuel will provide poor atomisation, compared to slightly warmer/less dense fuel.
Id like to know where the happy medium is between fuel density and temperature for optimal results. ( I honestly cant be fukd searching for the good thread on this, sorry)

Also should the fuel return always be plumbed to the tank? What about plumbing to the surge? The only con i can think of with this is returning hot fuel to your system, but how significant would the heat differential be between the two options? Also would the fuel being delivered to the surge counter-act with the return pressure and force its way up the return??


sorry, i could of said that a lot less complicated, but buzz words like 'atomisation' and 'differential' make me sound cool.

also sorry about swinging the topic my way a little. Quick, someone post something about turbo intake temps and get this thing back on topic.

[matt dunn]

Also should the fuel return always be plumbed to the tank? What about plumbing to the surge? The only con i can think of with this is returning hot fuel to your system, but how significant would the heat differential be between the two options? Also would the fuel being delivered to the surge counter-act with the return pressure and force its way up the return??

We ran a fuel cooler on our 1JZ Levin. It was put on when we first built it so have no comparisons.
I think a lot of the heat in the fuel comes from the engine heat tranfered in through the fuel rail to the fuel.

If you run a surge tank, the fuel is just about always pumped from the surge to the engine and back to the surge.
The main reason is that as said before a HP pump is used to feed the engine and a LP pump is used to feed the surge.

Your HP pump will flow 2 to 3 lites a minute out of the tank, and the LP pump will probably struggle to keep up, so if you dont return to the surge, it will run out of fuel.

[kingcorolla]

mmmm true.

so just keep an eye out on your flow rates of your pre and post surge pumps, and return fuel accordingly. Cool bananas.


ok back on topic now

[Stealer Of Souls]

oh and just for the record 5 dgrees drop at the intake might drop you 1 degree at the outlet of the turbothe heat is made buy the pressure that is been held in the intake
more pressure = more resistance
and we all know that resistance generates heat

Okay... now this I don't understand...

PV=NRT
Pressure increase. Volume is the same.
Number of mols increases. R is a constant. Dues to non-perfect system, temperature increases also...
If we double P, and (lets assume that) N goes up by 1.5 then T would have to go up by 1.333.

At intake to turbo if P is essentially constant at 1 atm (103kPa), V is essentially constant. We halve T then since R is constant N must increase to compensate.

So we then do the double P, T (which was previously halved) now goes up by 1.333, it's now .65 of the original value... And N is even more...

Am I wrong?

[Chickenman]

Only problem is the waste co2 gas then gets sucked into the motor...

Wouldn't happen on my MR2... I/C and intake are on different sidesesesesesees

[Monsterbishi]

You'd be surprised how far a cloud of co2 travels, unregulated, it'll convert from liquid to gas until it achieves a pressure of 800psi, if you could see the stuff(not just the water vapour that forms near the release point), a one second squirt of co2 through a 1/8" I.D. nozzle will create a cloud the size of about 4 cars.

Of course, power loss wise, it probably wouldn't do jack, since the car could consume said cloud just as quickly :>

If you really wanted to freeze the living daylights out of the intercooler, you could weld a expansion chamber on the top and bottom of it, then dump about 14 liquid oz of co2 through them with a vent nozzle straight out the back of the car, the amount of heat energy co2 can absorb during it's liquid->gas conversion is immense, right to the point where it'll instantly condensate and freeze on the surface about 1/16" of ice all over the expansion chambers exterior surface.

[Inane]

Wouldnt Water injection be a more efficient method of cooling the air?

[Stealer Of Souls]

Water injection would be quite efficient. But a CO2 system has other benefits.

Water injection can't suppress detonation but keeping temperatures down, but ulitmately is unlikely to reduce charge temps below ambient. CO2 systems are potentially capable of reducing charge temps to the negative region...

www.ARE.com.au have some interesting info on WAIC and dry ice box coolers. They did some testing of their designs. But they also mention thing like, a dry ice box (CO2 system) is best used in certain situations. Wouldn't suit a road car, due to the tuning requirements.