87 Hot Air

[Ormand]

Does too...

Posted by GS70350--
"No, the fuel injected into the ports does NOT normally vaporize, only a very small portion does, and only this portion burns to force the piston down on the power stroke. "

I believe you are wrong. The fuel which is injected is atomized by the injectors, into a stream of VERY fine droplets. These droplets are mixed with a very warm air stream, moving at high speed, and then this highly turbulent combination will enter a HOT combustion chamber. True, any droplets which are not vaporized will likely not burn... until they get into the exhaust. However, the percentage of unvaporized, and thus unburned fuel is very low, unless the engine is WAY out of tune. Even fuel injected when the intake valve is closed should vaporize when the flow through the 'venturi' at the valve seat creates a low pressure area over a hot surface. Those folks who like to run a lot more fuel than the engine needs will have unburned fuel past the exhaust valves.

Also posted..
"Interesting fact, is that some people say that a engine that burns fully vaporized gasoline, will have a cold or only slightly warm exhaust, which would not neccessarily be good for a turbo application"

The fact is "that some people say". That does not mean that it is TRUE!! An engine that burns fully vaporized gasoline is a normal engine, and the exhaust temp will be just lower than the combustion temperature for gasoline. Simple chemistry, simple physics. Gasoline burns, gives off heat, the combustion products are hotter and have more volume than the intake mixture. Of course, it is possible to deliberately make the combustion process inefficient, to get temporary power to the turbine for "quick spooling"; I think a lot of folks do this for the track. But if you tried to run an engine in that mode for very long, parts would be damaged, because of excessive heat in areas not designed for high temperatures.

The '86 and '87 engines have the SAME heads, and the SAME cam as the earlier engines, and the turbo is very similar. The '84 and '85 engines also had direct port fuel injection, and DIS. The PRIMARY advantage of the last two model years was the intercooler.

 

[bruce]

Port injection at less then 25% DC, firing at a closed intake, just lets the fuel puddle around the intake valve and runner floor.

Ford in the last few years has some some really interesting photo work of what happens. This puddled fuel is in very large part ATOMIZED by the self EGR'ing effect at overlap. The exhaust blowing back into the intake as the intake first opens apprears to be trans if not supersonic, and that blast hitting the pooled fuel blasts it into same droplets. Als explains why Ford went from valve open injection to valve closed injection.

So again it's not one of these written in stone ideas that folks like to pidgeon hole about how things work. At certains, there is more to be gained from atomized fuel, and at others vaporized.

Which brings us right back to what I was talking about in finding out the ratios about what works best, and when. Ratios meaning ratio of atomized to vaporized fuel.

And if you get all the fuel droplets down to like 10 microns or less the difference even further blurs about what's best.

And you can see a hidden slight advantage to larger injectors being a good idea, for low speed running since your doing a better job of keeping the DC under 25% as long as possible. And why some folks were passing smog checks with the cam sensor disconnected.

Then we can also look at how much vaporization does accur since the back of the intake valve can often be running at 600dF.

 

[GS70350]

Re: Does too...

Originally posted by Ormand

I believe you are wrong. The fuel which is injected is atomized by the injectors, into a stream of VERY fine droplets. These droplets are mixed with a very warm air stream, moving at high speed, and then this highly turbulent combination will enter a HOT combustion chamber. True, any droplets which are not vaporized will likely not burn... until they get into the exhaust. However, the percentage of unvaporized, and thus unburned fuel is very low, unless the engine is WAY out of tune

Do a little more research, and give me proof that your engine is burning nearly 100 percent of that fuel in a vaporized state, thus using nearly all of the potential energy stored in the gasoline to force the piston downward for power. The droplets continue to burn throughout the bottom of the power stroke, and throughout the exhaust stroke, and also out the exhaust. Vaporized fuel COMBUSTS, quickly, violently, completely. if so, and injected in the right amounts it would theoretically completely burn when the spark plug ignites it, and most of the energy would force the piston down that way. You are only extracting about 20 percent of the gasolines energy to force the piston down, the rest burns for practically no reason other than to make heat and quench the flame. However, you cannot lean the engine out to try and reduce this amount of wasted energy, since this is a %percentage thing. 2 liters of fuel, .5 liters vaporized, enough to run the engine right. 1 liter of fuel, .25 vaporized, wont run right, to hot. vaporized fuel when burned, will not really need to have any extra fuel to quench the flame. its more of a defect in the way we fuel internal combustion engines that can be addressed and corrected if they wanted to.

Originally posted by Ormand
An engine that burns fully vaporized gasoline is a normal engine, and the exhaust temp will be just lower than the combustion temperature for gasoline. Simple chemistry, simple physics. Gasoline burns, gives off heat, the combustion products are hotter and have more volume than the intake mixture.

not a normal engine, sure all the gas can vaporize, but the engine doesnt burn it. It only burns a slight amount of it for power. The rest vaporizes to late to be burned in the engine. At least on the power stroke.

Originally posted by Ormand
The '86 and '87 engines have the SAME heads, and the SAME cam as the earlier engines, and the turbo is very similar. The '84 and '85 engines also had direct port fuel injection, and DIS. The PRIMARY advantage of the last two model years was the intercooler.

Yes, you mentioned that this experiment was recreating the past, and i felt that the 78 to 83 CARBED cars were what you were tlaking about, not the 84 to 85. I know what they are. Main thing this is recreating is just having fuel enter the plenum or intake and possibly cool the air charge. Hot air 84 85s did not do this, they were port injection. The fuel on the carbed cars went with throughout the intake path, as it is kinda doing here with bruces 7th. This is what i was talking about. In the carbed cars, they were dinosoars in technology compared to the 86 87 and even the 84 85s. not talking about the intercooler being the experiment here.

Just the way i see it

 

[TType84]

The '86 and '87 engines have the SAME heads, and the SAME cam as the earlier engines, and the turbo is very similar. The '84 and '85 engines also had direct port fuel injection, and DIS. The PRIMARY advantage of the last two model years was the intercooler.

no.. the intercooler was not the primary advantage.

the turbo is bigger and puts out way less heat, even at ~15psi

the intake is gobs better, nearly perfect, as good as it can get without a rjc plate, compared to the 84/85 intake. im sure you know how horrible the hotair intake is..

the passenger header sucks too, it looks like it was welded by a 3 year old, every single primary protrudes into the main "collector" area by at least half an inch

the intercooler is not the main reason there are about 5 "main" reasons

 

[GS70350]

I second that

 

[Bruce Davis]

I'll 3rd that.

 

[99Formula]

Most of the talk here is a little over my head, but all the talk of intake cooling reminded me of an interesting new CO2 based product I saw at SEMA this year. Check it out here:

http://www.designengineering.com/cryo2_related_items.html

Peter

 

[Terbro]

Originally posted by 99Formula
Most of the talk here is a little over my head, but all the talk of intake cooling reminded me of an interesting new CO2 based product I saw at SEMA this year. Check it out here:

http://www.designengineering.com/cryo2_related_items.html

Peter

I like the idea...wonder if it effectively cools. Being that liquid C02 is ~ -370ºC, it's cold enough to have a green leaf shatter like porcelin if dipped in it. The challenge I would think is getting the L-CO2 to "stick" to the surface. Spraying this stuff around, it likes to bounce right off of stuff. One has to dip something into it for it to cool. Plus one must be careful not to have any of of the C02 gas come near the air filter...effectively robbing the ambient air of 02.

I better like the idea of some type of...dry ice blanket in front of the intercooler. Hell, design an intercooler with an outer jacket to fill with L-C02.

Terry

 

[GS70350]

As far as the intercooler idea, using dry ice, there may be something along those lines, but it never needs recharging and is sealed, and requires no extra wiring. I saw it a while back online, maybe a year ago. Intercoolers for the GN and the Sy/Ty, that utilized the factory AC system to cool the intercooler. No not with ducts, what it did was it basically made the intercooler core, a second evaporator core. So, the Freon was compressed, and then goes through a new expansion valve on the IC and as it passes over the IC core it cools it to what they claimed was about 30 degrees constant temperature without heat soak i believe. It basically just splices in to the stock setup. Thought it was a neat idea anyways, just turn on your AC to cool it down and then turn it off at the staging lights before your run.

 

[TRiv]

I 4rth that ( intercooler not the primary advantage of 86-87s), also must include the throttle body after the turbo as better design, probably the best change, also the electronics. The idea of trying to do the same thing with less is a good thing, this is after all the original concept behind the turbo v6 in the first place, and (hate to say it ) but the four cylinder crowd is doing it ( although more because of the car companies then them) is less weight, a lot less in many cases. It would be interesting to see data for the difference between the stock intercooled car and Bruce's set up, that is of course on how consistant the test conditions are, it seems that is probably the most difficult thing for most of us racers/rodders, accurate test results. Seat of the pants surely is'nt, nor is always the dragstrip, even a dyno unless the conditions are the same at testing; temperature, humidity,barometric pressure,etc. Of course any of these can tell you for gross improvements of upgrade performance, but for small differences probably not, accurate testing conditions is important. Still, like the idea of using less hardware to go just as fast, it somtimes looks like all the hardware added makes a small engine look more massive then the large displacement engines. An intercooler is still a good thing also but have to wonder how much "as is" do they help? One thing no one is mentioning here is airflow of the cooling systems in general, and the aerodynamics of the cooling systems as installed in the Regal body. We need to look at the efficiency of the airflow of the car in general, let's face it he Regal is'nt the most aero to start with, and with all those coolers: radiator, air cond, inter, maybe oil, plus all the 'stuff' under the hood, the front end is mostly bumper & headlights, how much cool air gets in and how does it get out? The only place it can go is under the car, and it's not very aero under there. Point is no matter size intercooler is being used or where it is, what is the airflow past it? Sure larger intercoolers help but just how much? and can they be made to work better? It's too bad Buick did'nt put large fender extractors (like the old Trans Ams) where those Grand national Intercooled emblems are, that may help get more flow past in through the engine bay, just a possibility. One other thing for anyones comment, although this wont do much good because it would be tough to fabricate, how about something like the air gap manifolds currently sold for Chevy motors that allows for cooler intake charge ( no hot oil on the bottom of the intake), actually many manifolds for carbed drag engines have always been doing this, maybe there is some othere way to isolate this heat. Heat is the enemy, and what goes in has to come out. One other thing, I want to look into this further but has anyone heard about any theories about plumbing at the output of any type of pump that for the most efficient output ( do'nt know the %), the lenght of tube/ pipe should be a minimum of 10 1/2 X the diameter of the output in length before any kind of bends? I've seen some applications of high performance engines ( Ferrari, race boats, planes, etc.) where this may have been taken into consideration.

 

[GS70350]

Originally posted by TRiv
We need to look at the efficiency of the airflow of the car in general, let's face it he Regal is'nt the most aero to start with, and with all those coolers: radiator, air cond, inter, maybe oil, plus all the 'stuff' under the hood, the front end is mostly bumper & headlights, how much cool air gets in and how does it get out? The only place it can go is under the car, and it's not very aero under there. Point is no matter size intercooler is being used or where it is, what is the airflow past it? Sure larger intercoolers help but just how much? and can they be made to work better? It's too bad Buick did'nt put large fender extractors (like the old Trans Ams) where those Grand national Intercooled emblems are, that may help get more flow past in through the engine bay, just a possibility.

Good thought. so far all i know to do is pull off the rear hood weatherstripping, grind down its ridge that it sits on. Then for the trans am like thing, install a set of GNX fender vents and cut out holes in your inner fenders too so that air actually gets through to them. That could help, i know on mine, when i stop and have the fan running, i can get out and put my hand by my vents, and air comes out, hot air. seems to work.
Under the car is where most goes, so how about making a belly pan for the front of the vehicle? id like to try it, but i dont have access to a lift. kinda hard on the concrete. I figure just make it so that its smooth underneath so you have less turbulence, but also at the back area of the engine, put a slit, and make it a low pressure area somehow to hellp pull and suck the air out from the engine compartment. up front design a large airdam like the factory one, just about twice as tall. I did this but it didnt look right. ill attempt to do so again later

Originally posted by TRiv
how about something like the air gap manifolds currently sold for Chevy motors that allows for cooler intake charge ( no hot oil on the bottom of the intake), actually many manifolds for carbed drag engines have always been doing this, maybe there is some othere way to isolate this heat.

Air-Gap intake, as far as i know, the intake manifold we currently have on the 86 87 cars, the factory one, is basicall an air gap intake. The runners and plenum floor do not contact the valley or whatever i dont think. Also ive seen some old stage 2 intakes for the v6s that looked like the edelbrock air gaps you can buy today.

 

[Turbojorge]

Originally posted by GS70350
so far all i know to do is pull off the rear hood weatherstripping, grind down its ridge that it sits on.

That right their was worth a solid .10 and 1mph on my car. I'm dead serious! You NEED to give it a try. It never fails.

The GNX vents would also be a good idea. I would like to do that when I'm ready to paint the car.

 

[tracer]

Bruce, need an update on the hot air. When is the kit coming out so I can ditch my IC ?

 

[monte_383]

Bruce, any recent activity or updates to report on this. Still working well? -Chuck

 

[TheNovaMan]

TTT (I'm interested too.)