hotair nozzle placement

[burnout]

I was reading a post from awhile ago that Lee was spraying alky through the TB on his hotair. I was wodering if anyone has also tried it there? I don't want to take my intake off till I have to. ( I just got everything back together.) I'am using my turbo to intake adapter plumbed with my NOS fogger nozzle. If need be I can wait and just plumb it in the back of the intake later.


Burnout

 

[redhotrod]

sorry burnout I don't have an answer for you, but just wanted to chime in that I would think on the hotair it would be more efficient if it was sprayed into the cold side of the turbo(tb side), that way, the alcohol isn't getting wasted out the wastegate. I am seriously thinking of installing a diy kit soon, just waiting for a paycheck. I was thinking of plumbing the jet into the hotair turbo adaptor neck, that way you wouldn't need to take the whole intake off. Only reason I would see this not being a good idea would be because of the alcohol eroding the aluminum intake.
where can I find that post about Lee?

 

[Steve Hill]

nope. Alcohol (and water) thrive on heat, even after vaporization.

 

[redhotrod]

wouldn't be better to inject the alcohol into the combustion chambers, isn't that what its all about? If we inject it in the up pipe, wouldn't it just go in and out the hot side of the turbo, without ever getting into the combustion chamber? I understand the hot side of the wheel would be cooler, and the exhaust, but how exactly does it cool the internal engine? I guess I'm not so familiar with how the intercooled engines up pipe is configured. the hot air setup is with the passenger side header going into the turbo via up pipe, then from the turbo, out the downpipe to the exhaust. What am I missing here?

 

[burnout]

I might try it through the TB I'am not really in a hurry to do this just like to have all my info in advance. We need Lee to chime in and give us a run down. If you installed the nozzle 6 or 8 inchs from the TB the alky would atomize before it hit the turbo and it would just be could air. I bet it would work good you would just have to play with nozzle placement and jets.


Burnout

 

[redhotrod]

Burnout,
are you thinking of installing the jet in the MAF pipe?

 

[burnout]

Yes

 

[Steve Hill]

maybe I misunderstood. Best use of the chemical properties of alcohol and water would be to inject just before combustion chambers, like in the plenum. Just have to be thoughtful about even air distribution and no sharp bends. Gentle bends ok.
For a few good reasons, you should allow nothing but air going through any turbo.

 

[redhotrod]

I understand about just letting air through the turbo, so it wouldn't beat up the compressor wheel and erode it so bad. So I would expect plumbing the nozzle under the turbo would be fine, after the alcohol is turned on to spray, the turbo would blow the alcohol/air mixture into the combustion chambers.

 

[R-R]

Originally posted by Steve Hill
maybe I misunderstood. Best use of the chemical properties of alcohol and water would be to inject just before combustion chambers, like in the plenum. Just have to be thoughtful about even air distribution and no sharp bends. Gentle bends ok.
For a few good reasons, you should allow nothing but air going through any turbo.

I was under the impression that water/alky injection was best farthest from combustion. I have no scientific basis for that --it's just what CW seemed to be from everything I'd read. So you're saying after the throttle body would be better than somewhere before it?

 

[Steve Hill]

no expert here either, and just my thoughts on this.
There is a balancing act going on. You want the best and most complete vaporization possible. Water and alcohol take a lot of heat to vaporize, and then must stay vaporized.
So, ideally you'd inject it close to a heat source. But there are air distribution irregularities to consider. The plenum is a pretty busy place. Since I have no way of visualizing what's going on in there, I chose the airstream feeding the plenum as the next best place to inject. This might have it's problems too, thanks to the 90 degree turn the air has to make, which can cause seperation.
After all that, I just went with what seems to work.
I've have used locations of one inch from the throttle blade, to a more relaxed location a few inches farther away. No noticable difference.

 

[burnout]

Steve do you have a hot air? The only thing that might be a problem is slowing the wheel down when sprayed. But then again if you placed it far enough back it might not. I not worried about corrison on the wheel the PCV system goes through the TB so the oil from that will work as a lube.


Burnout

 

[Steve Hill]

I have a '87 TR, and my comments relate to that.
I know, in the past, there have been people who were spraying into the turbo. Heck, even GM did it once! I still stay you're asking for problems. Good luck!