Inlet temperature help pls

We run a blown pro charged 417 cu in ford Engine on alcohol injected . We are now making close to 70 lbs of boost due to hi inlet temperatures of 400 deg we used to make 43 lbs at same blower speed on Gas with water intercooler as outlet temp reached a max of 80 deg . Our questions are if there was a way of injecting alcohol into the outlet tube coming off the blower yes we know it could be a bomb but we can turn on the injectors to only come on at 30 lbs of boost to help cool the inlet charge or are we better off adding the 120lbs of weight back in the car and going back to our intercooler . Does alcohol injected either into a blower like this actually work to reduce inlet temps as well as the intercooler or are we wasting our time with this ?

 

temp

you bet it cools it down at least 40 deg

 

Im not sure that 40 deg would even make a dent in what we are seeking we need to cool it down to under 200 and we are currently at 400 deg hence why boost is so high .

 

Also, there is the negative return of so much boost creating so much heat actually eating up any hp gain from the increased boost. You end up beating up the air.

 

Since no one has answered your question here goes,

The latent heat of vaporization of methanol is 1008 we will round it to 1000 meaning that if you evaporate 1 gram of methanol it will absorb 1 btu of heat during its vaporization so if you measured the amount of water that you put through your air to water intercooler and the amount of temperature increase it would be easy to calculate the amount of methanol that you would need to evaporate to achieve the same amount of cooling.

That said I have run the numbers for your motor assuming that you were using 1008 cubic inchs of air ( a cylinder fill rate of 240% ) and by my calculations which were admittidly very rough you would need to vaporize .33 gallons of methanol per second to achieve 250 degrees of cooling on the charge temp. So if you were achieving 50% evaporation then you would need to feed .66 gallons per second to the injector.

As Mike alluded to pressure equals heat so as you begin to remove heat you also reduce pressure and that in turn reduces the amount of heat generated by the compressor, so it has a synergistic effect.

Because of this the actual amount of alcohol needed to reduce the charge temp will be less than you would expect if you only account for the mass of air and the amount of cooling that the alcohol would provide, how much I don't know.

The long and short if you keep the tube length to a minimum and keep it on the other side of the firewall and provide a burst panel then the fire bomb aspect should be acceptable, and I think you will be able to evaporate enough methanol to cool the intake charge and increase its density to a point where you will have greater efficiency than with the c16 and intercooler.

Richard Gavle

 

I know guys that run turbos that have injectors right after the turbos to achieve the affect you are talking about.

 

I don't think that's as much of the issue here, since it's a procharger (belt driven turbo).

The issue is it's simply too much overdrive on the blower, leading to excessive boost to the point that it's super heating the air.

Drop your boost down and I bet you see power pick up. Canter (as always), hit the nail on the head.

 

If I read it correctly, you are saying that by simply removing the intercooler and changing from petrol to alcohol, the boost reading in the manifold has increased from 43lb to 70 lb ? Is that possible ? Are you sure nothing else has changed ?
Do you know what the temperature on the original setup was before the intercooler ?
Jim

 

yes according to the perfect gas law it works out exactly we were running 43.75 lbs boost at 80 deg on the intercooler on Gas now our inlet is around 400 deg so hence why we have 70 lbs of pressure . p1t2=p2t1 t1=300kelvin =80 deg t2 478 kelvin =400 deg p2 70 psi x 300 kelvin so we have done the calculations so we know this to be true . We are scared of putting the alcohol in just after the blower as in case there ever was a backfire . we are racing this weekend with the intercooler and will let you know the results . We are leaving starting line at 39 deg and end of the run we are at 80 deg . not sure how it will affect things . Ps we arent even driving the blower as hard as we have in the past on Gas .Our Egts get to hot and the Engine shuts down around 1250 and to keep it even this cool we have to Run 3.8 A/f In high gear and it runs like a toad there . we had added two .080" lines that activate at 30 lbs of boost to the intake elbow just after the throttle body all they really did was add some extra fuel to the mix and were running 4400 lbs per hour of fuel which is way to much for this engine . When we lean it out to 4.2 and trust me it runs like gang busters here .99 60 foots etc.. it starts to detonate top of first gear . we tried the slower blower speed car wouldnt hit its own butt slowed down to 7.0 from mid 6.60s so that isnt the answer tried timing as low as 20 deg high as 30 deg trust us tried everything Inlet temperature just to High . car should run 6.40s easily .

 

Im no mathmatician so I will trust that your figures are good. 120lb sounds like a minor penalty to reduce inlet temperature by 320! degrees, plus whatever reduction alcohol helps. Good luck and I would be interested to hear how it works out.
Cheers.
Jim

 

"If" your rules allow this, I would keep the intercooler AND run methanol AND keep the meth delivery right at the intake port near the valve(s). This will give the optimum result and you can probably bump the static/dynamic compression as well.

You can fog the intake tract upstream (downstream of the impellor) with methanol, but you have to flow a fair bit of meth unless you have a long latency time. However, long latency time usually means more volume, and a much bigger potential for a bomb. One trick, if you do want to add upstream fuel, is to make sure that it is very finely atomized and dsitributed and preferably delivered at a much higher pressure differential than what your EFI injectors run at.

The Ecotec guys have tried all of this every which way possible. The fast guys have all gone back to air/H20 intercooler and meth right at the ports and manifold dry.

 

I assume this is a port injected deal so the alcohol never affects the intake charge till just above the intake valve as opposed to a conventional deal where it is sprayed through the blower using the port nozzles to balance flow.


The other downside other than the wieght of the intercooler is the flow restriction it will create which will be significantly greater than the loss created by the added mass of the alcohol in the intake tract.

Then there is the bomb deal...

Hell the worst thing that could happen is the backfire would blow the junction point between the rubber hose and the metal pipe without hurting the blower, the car would keep running and fill the entire hood area with fuel mixture then it would ignite

 

Big kabooommmm.......

 

My 2 cents

The one procharger setup that I know of in tractorpulling runs about 40 psi boost and fights temp. problems.
I don't know the exact numbers but I was surprised to hear a centrifigual charger makes that kind of heat.

The 4000 to 5000+ HP turbo alky 6 cylinders had hot intakes in the beginning. They were running about 70 psi and now they run more. Many have gone to water to air intercoolers. They drop the boost number by half and the temperature by half and make the same amount of HP.

The 3000+ HP diesel 6 cylinders have injected water right after the turb's for many many years.

If it were mine I would leave the intercooler on and inject right after the charger.

 

Fuel in Tube

We run a sb 430ci Ford Mustag, MFI system, alcohol, F3, w/4 120lb injectors in the tube to cool the charge down. 7.0's at 200mph at 3050lbs 10.5 tire. Never had problems.

Good Luck.
Andy C.

 

Like I said it will work no problem but you do have the chance of


http://datacore.sciflicks.com/the_fifth_element/sounds/the_fifth_element_badaboom.wav

 

Kaboom

Here's an approximately 5000 HP inline 6 cylinder, 3 turbo's, alky.
This is one of the best, of course not at there best moment here. I always wondered why they wouldn't run a burst panel?

http://www.youtube.com/watch?v=p_Y0B-kQUN8

 

Even more potential for a bigger $$$ kaboooommm, plus from a thermodynamic energy management point of view this makes little sense. Sorry, not trying to shoot down your idea intentionally.....