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General Information => FAQ/Tech Tips/Please Read First => Topic started by: DVST8R on April 13, 2006, 12:41:30 pm
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It seems to me that once a week now I am seeing "propane is like the nitrous of diesels" So I have decided to do a little write up on them. You may remember me from such threads as "More power for your 1.6td" and "200whp or 200bhp" :roll: anyways on to todays subject.
Propane is NOT the Nitrous of diesels! it is a myth of the internet, much like the myth of waking up in a bathtub missing your kiddneys after a night of driniking with a hot girl. Propane is a fuel, as such adding propane to your diesel is much like putting in bigger injectors or a bigger injection pump, with one differance being is that normally as you add propane you loose smoke, where as you add diesel you add smoke. The real problem with propane in an IDI diesel engine such as our beloved 1.5 - 1.9's is the high CR of 23.5:1 this is even to high for propane and its high octane rating of 118 (seems to vary some by sorce just took an average). As such it begins to cause detanation simillar to to high of a CR in a gas motor, with very small doses, from others experiance on this board, the max power attainable is only about 5%, after which it blows the head off...literally!
As such I will not go into how to build a system for ones vw as it is more pain then power.
Propane is a good modification for those with DI diesels as they run a lower CR as well as the combustion area seems to be more to the liking of propane. As such you will see it as a common power adder for any of the big three or newer TDI's.
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Nitrous on a diesel is very much like nitrous on a gas motor... imagine that :P
It is an oxidizer, meaning it adds more air. In adding more air it has one other very important property, it cools that air significantly. As such adding nitrous to your diesel is more like adding an on demand big turbo, with really really good intercooler.
Next you cannot lean out a diesel and blow it up like you can with a gasser, as such nitrous is very safe to play wiht on your diesel. In fact the proper tuning method is to goto your local track and turn your juice on, brining with you a bunch of differnt jet sizes and run it with a bigger jet size each time down, untill you slow down and then return to your fastest one. Because nitrous is an oxidizer and NOT a fuel, the only way it will make more power is if you have an excess of fuel, which is why alot of guys run nitrous with propane on there DI diesels, but since we are here to discuss for the most part IDI I will stick with that. So what this means for us VW guys is that in order for nitrous to be worthwile we need an excess of fuel to burn, the easist way to tell if you have that excess of fuel is go for a run and see if you have a thick black cloud of smoke following you even at max boost. If you do you are ready for nitrous.
Again here I will not go into designing a nitrous setup for your car, as there are lots of manufatures out there who have diesel kits that will work for you app. Nor will I recomend jet sizes as it will very from car to car and even day to day with the same car due to atmospheric conditions. So just cause "johhny" used jet "A" when he was at the track last weekend and your car is setup "close" to the same, this week at the track dosn't mean that jet "A" will be anywhere close to what you need.
My personal favorite way to run nitrous on a diesel which I will warn you right now is expensive, is with a progresive contorler. I run my solonoids empty or wide open, no jet at all, and then use the controler to setup how much nitrous I want to run and how fast I want it to come on. It makes tuning easy, as well as it has good launch control, but unless you are serious about it or just have a bunch of $$$ burning a hole in your pocket you are probably better to run jets.
One last note on nitrous get a bottle blanket as it is nessacary to make repeated consistant runs, nitrous performs the best at 1425-1450psi as such it will need to be heated or cooled for the best and most consistant runs.
Okay fine this is my last note, :wink: , If you are running your nitrous on the street as most people like to do a remote bottle opener is great, as then if a makeshift showdown occurs you can be at your best, instead of being I would have been able to take him if my bottle wasnt closed in the trunk. If you only use it at the track, it is a waste of money.
That is all for right now. Make sure to tune in again when Cetane Racing brings you such topics as "a 14sec 1.6 n/a" and "Stickers, where are the dang Cetane Racing stickers!?!"
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About time someone did a write-up on this. Good stuff.
I find the "propane for diesels is like nitrous for gas" statement annoying too.
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thanks, I always wondered about that - didn't make sense to me as I knew nitrous was a supply of oxygen.
so... if you had a N/A diesel with a TD pump (with the LDA) could you hook up nitrous and let the pressure control the LDA?
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thanks, I always wondered about that - didn't make sense to me as I knew nitrous was a supply of oxygen.
so... if you had a N/A diesel with a TD pump (with the LDA) could you hook up nitrous and let the pressure control the LDA?
:wink:
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neat - I have an extra n/a motor (pump does not have the LDA - yet) that I was wondering what to do with. Now I know it has potential.
Care to shed light on how to get excess fueling from a N/A pump? Giles rebuild? other than a Giles rebuild? GTD nozzles? governor mod?
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neat - I have an extra n/a motor (pump does not have the LDA - yet) that I was wondering what to do with. Now I know it has potential.
Care to shed light on how to get excess fueling from a N/A pump? Giles rebuild? other than a Giles rebuild? GTD nozzles? governor mod?
This really should be moved to its own thread in IDI engine, but in short... Yes.
A govoner mod would be done in a Giles performance rebuild, and is your best bet, and either gtd's or when ever fspgtd relases his monster nozzles.
I will only leave this here for the next day or so and then I will delete it I like to keep the FAQ on track and simple, I recomned deleting your reply and moving it to its own thread. :)
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i always had a feeling,,with the hi compression,,,,propane no good makes too many bad things happen in the 'hole,,,nitrous(lol) seems verry safe,,its basically like adding extra "air",because then you can over fuel it easy,if needed,i figure it would clear up smoke,,shoot,,iwould have to carrya 50 pound bottle around,it wouldnt be good,,id be lol'in all the time,wouldnt be able to stay out of the lol :shock: :D
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Just curious what you're using for progressive control? I've used progressive controllers on gassers before, and I agree - it's the cats meow for nitrous. :)
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Just curious what you're using for progressive control? I've used progressive controllers on gassers before, and I agree - it's the cats meow for nitrous. :)
im sorrysir,,me?? i dont have lolgas but if i did,id need to fill the bottle daily,,im nuts like that,,,,,i would think a controller that increased lol flow with boost would be nice ,,,, i would think on an na,,you would have to set it up for overfuel all the time,then the lol would clear up the smoke,,maybe a turbo pump on an na,,,,,,oh i get the post further up :idea: ,,turbo pump to add the fuel when the lol is hit,,,,why use pressure to push the lda(big truck guys call it an afc,AirFuelControl) down????you have vacuum from the vacuum pump,,use it like the na setups with the altitude compensator,and pull vacuumunder the diaphram to pull down the lda???????????use one of those "air switches " ive posted about to turn on and off the vacuum signal to the lda,,,or use a solenoid to open vacuum ,and whenthat solenoid is activated,,the lol solenoid is tied toit also,,,,,,?????hmmmm :idea: :idea:
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Just curious what you're using for progressive control? I've used progressive controllers on gassers before, and I agree - it's the cats meow for nitrous. :)
The last one I ran was a NX maximizer2 or mabey just the originol maxamizer I dont recall for sure, in any case it was complete overkill for my needs and was about $800usd. I think I only used like 5 of the functions ever and only like 3 on a day to day or race to race basis and it has like 30 or so... if you have a bunch of $$$ burning a hole in your pocket, or race competitvly then id highly recomend it as one of the top ones out there, but if your like most of us, there are a lot cheaper less sofisticated controllers out there. :wink:
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i dont know too much about it,,but lookin at the parts avalable from NOS ,,couldnt ijust get a "fogger" nozzle,and plug the fuel side, a nos solenoid,stickit in the intake,like my water injection, or actually you could stick it in the compressor side,and say see ya?? yea progressive etc,is nice,,but im talkin lo buck,,,,,, like iwouldnt do it unless it was less than 150 right now,,im tapped out :cry:
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Could this potentially be used to fill the 'hole' before the turbo starts to get up to speed. Maybe 1500 ~ 2000 rpm, or help kick it in (using the lda idea to match fuelling)?
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Could this potentially be used to fill the 'hole' before the turbo starts to get up to speed. Maybe 1500 ~ 2000 rpm, or help kick it in (using the lda idea to match fuelling)?
Yup.
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i dont know too much about it,,but lookin at the parts avalable from NOS ,,couldnt ijust get a "fogger" nozzle,and plug the fuel side, a nos solenoid,stickit in the intake,like my water injection, or actually you could stick it in the compressor side,and say see ya?? yea progressive etc,is nice,,but im talkin lo buck,,,,,, like iwouldnt do it unless it was less than 150 right now,,im tapped out :cry:
Sorry I totally missed this post :oops:
In anycase that is essentially what a "dry" setup is. Before the controller I ran a nozzle from a dry setup that a friend gave me when he went from a v8 to a 4 banger, and just adapted his nos system. I had it tapped into the top of the intake manifold elbow, pointing straight down (as I look back on it now, probably not the bes setup as 2,3 where probably running alot leaner then 1,4 but then again they always are base on that intake manifold... but that is another story) I then ran just a nitrous solonoid (with whatever sized pill I happend to feel was right for the conditions) A saftey swtich (also known as an arming swtich) and a WOT swtich, Relay, -3an lines to the bottle and finally a purge setup. Most of my originol setup was used pieces from friends or swap meets and cost me about $50 + a bottle (got it used as well for about $75) so for $125 and about a half days work to install it plumb it ect.. I had a setup that they sell for like $700 :roll:
I kept that basic system and added a remote bottle opener, a blanket, and then eventually the progressive controller. If you take your time and piece it together you can have a good system for under $150. :D
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Couple more helpful tips;
1). Check your system for restrictions other than the jet. Your jet may not be the smallest restriction in your system, therefore not allowing you to get the most out of your system as well as not giving you full tune ability of the system.
You should check your nitrous line sizes, mostly between the solenoid and the jet. If you are running a -3an hose, most likely the inner crimp will be .079, meaning anything larger than this in a jet will yield little to no change in flow or performance. Nitrous companies produce -4an hoses that have a -3an nut on one end. Since this uses a larger hose (-4), the inner sleeve on this -3an end will have a larger inner diameter (most are .144 to .154). This will ensure that the jet remains the smallest restriction and therefore the final tuning tool in the system. Also check the fittings and nozzle used and keep the solenoid orifice size in mind too. You can always run a larger solenoid or two solenoids/two nozzles to get more flow.
2) Also, if running more than one jet, don’t assume two .050 jets are the same as a single .100. Flow is basically based on pressure and cross sectional area of the jet. This is helpful is you are running two systems that get staged during the run or if you run two jets in different spots in the intake tract on the same stage (1 jet pre IC and and 1 jet post IC, etc.). Below are a couple of formulas you can use to go from multiple jets to a single jet;
From multiple jets to a single jet,
Dia. X Dia. X .7854 X N = total jet area
Where N is the number of jets and Dia. is the inside diameter of the jets
As an example we will compute two .050 jets.
.050 x .050 x .7854 x 2 = .003927 total area
Now that we have the total area we need to compute what single diameter jet the total area equals. And it goes like this;
AREA / .7854 X SqRt
.003927 / .7854= .005
.005 times square root (just hit the square root key) = .070710
Rounded off = .071 jet.
So two .050 jets when flowing at the same time are equivalent to a single .071 jet.
The next example is if the two jets used are different sizes (a .050 jet and a .085 jet);
.050 x .050 x .7854 x 1 = .0019635 (a single .050 jet area)
.085 x .085 x .7854 x 1 = .0056745 (a single .085 jet area)
Add these two areas together to get the total jet area
.0019635 + .0056745 = .007638 (total jet area)
Now that we have the total area we need to compute what single diameter jet the total area equals.
.007638 /.7854 = .00972498
.00972498 times square root (or just hit the square root key) = .0986153
Rounded off = .099 jet.
So a single .050 jet and a single .085 jet when flowing at the same time are equivalent to a single .099 jet.
Got it? Good, cause now I'm confused...
:P
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you should hear all the kids who threw up a fuss when i said about running nitrous on a diesel, and when i said about running both. they tried to tell me that nitrous will hardly do anything, if it does something at all, and when i asked why, the answer is, because it's a diesel. which obviously it is not a reason. and when i said how nitrous work, because it is 1/3 oxygen which quickly breaks down in cobustion, and in the atmosphere we only have 21% oxygen, so theres a big power boost, plsu it cools all that air down adding even more air. but of course they told me it was just cause the air is colder. after they wouldn't shut up about it, i just starting giving them these :roll:
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Being from the propane industry, I found this article in a trade publication enlightning.
What it is...and why:
Simply stated, Propane (LPG) Fumigation is the introduction of gaseous propane into the air intake of a diesel engine for the purposes of attaining more power, economy, or both. The parallel is often made between fumigation and using Nitrous Oxide on gasoline vehicles to achieve a power increase. Basically, this analogy is correct, although the properly implemented use of LPG on a diesel engine will actually result in a better-running engine without the possible damaging effects that N2O has on gas motors.
Exhaust emissions are reduced as a result, with lower quantities of unburned hydrocarbons and fewer particulates (smoke). LPG fumigation will even clean up the odor of diesel fuel in the exhaust, making the smell from the tailpipe of an engine utilizing it much less objectionable.
How it works:
Introducing LPG gas into the combustion air intake of a diesel engine acts as an accelerant, promoting the even burning of the diesel fuel, and more complete combustion, resulting in more power being produced. Many web pages and forum posts will call LPG a "catalyst" but this is not correct, as LPG creates no change in the molecular makeup of either the air or the diesel fuel.
Propane by itself will not self-ignite inside a diesel-fuel compression-ignition engine. During the compression stroke, the air/LPG mixture is compressed and the temperature is raised to about 400?C, not enough to ignite the LPG, which has an ignition temperature of about 500?C. When the diesel fuel is atomized into the cylinder under high pressure, it immediately self-ignites (diesel ignites at about 385?C.), and causes the LPG to burn as well. Since the LPG is in mixture with the air, the flame front from the diesel spreads more quickly, and more completely, including igniting the air/fuel mixture which is in contact with the cylinder walls, which are cool in comparison to the super-heated air inside the combustion chamber. Much of the cleaner burning of the fuel is attributed to this ignition against the "cooler" components of the engine, and accounts for raising the percentage of combustion from a typical 75% for a well-tuned diesel engine running on pure diesel fuel alone, to 85-90% with the addition of LPG. Obviously, this more complete combustion also gives a nice boost in power, with an accompanying increase in fuel economy and reduction of pollutants.
What to Expect:
OK, here's where we have to draw a distinction between engine types. Normally-aspirated engines require different systems to introduce the gas than do turbocharged engines. The results are different as well.
Normally-aspirated (N/A) engines will realize only a modest gain in power by the use of LPG gas. Displacing 1% of the intake air with LPG will result in a small power increase, perhaps 5-8%. Nearly no increase in power will be noted at full throttle, assuming that your injection pump is correctly adjusted already. Attempting to provide more gas to the engine will not increase performance, and will in fact lead to a condition not unlike pre-ignition in a gasoline engine. This has been attributed to excessive peak pressure inside the combustion chamber, and may have a lot to do with the fact that most N/A engines are also IDI (Indirect Injection), which means that the diesel fuel is not injected directly into the combustion cylinder, but instead enters a "swirl chamber" where ignition takes place. The flame front then shoots out of the swirl chamber into the combustion chamber, where it combines with the air (and LPG) to force the piston down in a power stroke. Apparently, these engines have a problem in that the flame front exiting the swirl chamber ignites the LPG/air mixture, all of which burns instantly instead of in a metered, controlled manner as it would during the normal diesel injection window.
I have had satisfactory results on my VW 1.6 N/A engine when adding LPG at a rate of 8-10% of the BTU rating of the diesel the engine is using. It may be possible to turn the fuel up, but I do know for sure that too much fuel does not increase power, and causes the engine to make very unhappy noises.
It's worth noting that if you experience a big increase in power on a naturally-aspirated diesel engine after installing an LPG fumigation system, then you should go back and check to see that your injection pump was adjusted to provide a nearly stoicheometric air-to-fuel ratio at maximum throttle without the LPG turned on. It's possible that the significant power boost you are seeing is due to the engine now being adequately fueled for the first time. The additional BTU content of the LPG is simply being substituted for the diesel fuel that you haven't been injecting all along.
Turbocharged diesel engines are able to realize a significant increase in power by using LPG fumigation. While the usual suggested increase is considered to be approximately 20%, by careful management of the gas introduction, power gains of up to 40% are possible. My understanding is that it is a very fine line between lots of extra power and a dose of LPG that will render an engine scrap metal in a hurry, so consider carefully before you decide to "turn it up".
Turbo engines are by design blessed with a lean air-to-fuel ratio, and can be fed concentrations of LPG up to about 6-8% of the intake air volume. TDI (Turbo Direct Injection) engines have shown dramatic power increases when properly fumigated with LPG, combined with an "Upsolute" chip, or computer engine management upgrade. (Of course, these modifications will void any manufacturers warranties...)
Types of systems:
I am aware of two basic fumigation systems.
The first, I call the "dump" system, which means that you pick a value of propane to feed to the engine, either by calculation, or by trial-and-error, and you simply "dump" it into the air intake. Little provision is possible for correcting gas flow depending on engine load, so the system is probably only optimized for one type of load demand. The advantage is that this type of system can be cobbled to together by backyard experimenters like myself at a low cost. The disadvantages are that you will probably need to error on the side of caution to make sure that you aren't overloading your engine with too much gas, and that the system doesn't compensate for variations in engine speed, load, etc.
The second system is much more sophisticated, and uses a variety of sensors and controls to monitor engine performance and load, and adjust the gas flow to suit the need at the moment. Most commercially available systems will be of this type.
In order to determine the load on the engine in a N/A system, a venturi must be placed in the air intake, as diesel engines have no natural intake manifold vacuum. A sample of the vacuum produced by the venturi is fed to a metering system, either electronic or mechanical, which adjusts the gas flow to suit the circumstances.
Turbo engines have a great indicator of load built in. It's a fairly simple process to take a sample of the boost pressure developed by the turbocharger and use that to control the metering system. Most commercially made systems are designed for turbo engines, both for this reason, and because of the greater power gain that the turbo realizes from fumigation. Since boost is such a reliable indicator of engine load, higher values of fumigation can be realized, with tighter control over the results.
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Could this be used to help with the dreaded hard cold starts that the franken engines are encountering? Kind of like an advanced cold start lever?
Does anyone know if 635Racer's new manifold has a provision for anything like this?
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Could this be used to help with the dreaded hard cold starts that the franken engines are encountering? Kind of like an advanced cold start lever?
Does anyone know if 635Racer's new manifold has a provision for anything like this?
Interesting idea about using a constant spray of propane to help with cold starts, but I don't think the franken engines have serious cold start problems. Chris' franken engine couldn't start well because he had a bent valve. My franken engine couldn't start well because I had a modified 1.9TD head deck (PP's stage 4), which lowered compression further, and a 3-hole headgasket that was too thick.
After fitting a headgasket with the correct thickness but still with lowered compression, my franken motor fired up instantly (only ~1 crank, at most 2 occasionally) in 0 degree C temperature. There was quite a bit of white smoke during the first 30 secs of driving after cold starting but the cold smoke level went down after 10,000km of break-in.
A healthy 1.9TD head on a healthy 1.6TD block without lowering compression further (via bent valve(s), an aggressive camshaft, thick headgasket, modified head deck) should be fine for daily driving from 0km. I have not tried it though. I may have missed it but I haven't seen anyone complain about cold starts with this basic franken setup.
While a ported 1.9TD head already gives improvements over a 1.6 head, I still would go for a modified deck for better airflow and drive it on the street. :D
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It'd be fantastic if cold-start propane will make 17:1, 18:1, or lower compression TDs streetable. The quicker ignition of propane could reduce smoke and increase engine smoothness during cold start.. I have not heard of propane used in low RPM and low load applications though. Does anyone have theories or more importantly practical experience?
Coleman Propane mini-BBQ tanks can be obtained easily and affordably at a handful of local stores (e.g. Superstore, Walmart) if a large propane tank is not desired, or if an e-z back-up is needed.
The following is my suggestion on how the "cold start" propane (if feasible) system should be wired up (fully automated, no switches):
1. Propane is injected while key is in "start" position, i.e. while the engine is cranking, not flooding the cylinders before the engine is cranking.
2. A coolant temperature switch will continue propane spray as long as the coolant is still cold, e.g below 70C or user preference. Key must stay in "on" position for propane to continue spraying. Propane will continue spraying only while the accelerator is not pressed, which implies engine idle (use the factory electric "off" switch on the fuel injection pump to trigger spray - or make a simple custom switch).
If the coolant temp is high enough, the propane kick-start (#1 above) can also stay disabled. It's up to the user.
3. Turning the key to "off" will turn off propane automatically.
Gotta be careful not to load the cylinders with excess propane while the engine's not running. If you mess up your clutch engagement and stall the engine, spray can continue while the key's still in "on" position. To prevent this, tap into the RPM sensor from the alternator. If the RPM signal is weak (e.g. below 800 RPM), then it will automatically disable propane.
The RPM switch is easy and can be put together for under $100. Buy the Dakota Digital RPM signal converter (~$60), a generic shift light. Autometer has a shift light with user-set shift points.. pick a 800 RPM shift point. Modify the shift light so instead of turning off the light below 800 RPM, it cuts off the propane system. Very basic wiring.
If desired, a separate RPM shift light can be added for the key "start" position, to disable propane below 50 RPM or whatever the cranking speed is.
4. There can be separate propane injection solenoids for #1 (start) and #2 (idle) above. I.e. use more propane flow for #1 start (while you are holding key to "start"), which will kick up RPM, and use controlled propane flow for #2 idle (while key is in "on" position) to hold idle at 1,200 RPM or whatever works best for your motor.
5. A master switch can be installed if propane needs to be permanently disabled.
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It's my understanding that the percentage of propane to diesel fuel is critical (more is not better, but worse) as it is an "enhancement" only. The propane valve is a throttling valve and regulates based on diesel throttle position. I don't see it as being a starting aid, but a full-throttle power/emissions booster.
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It's my understanding that the percentage of propane to diesel fuel is critical (more is not better, but worse) as it is an "enhancement" only. The propane valve is a throttling valve and regulates based on diesel throttle position. I don't see it as being a starting aid, but a full-throttle power/emissions booster.
So you don't think propane will work as a starting aid? Anyone else share the same thoughts? Some people have used more volatile liquids like acetone etc. to help improve starting - although stupid as it might be. Is there any liquid/gas other than propane that can be used to boost starting safely?
When my engine compression was really low, I had to crank ~10 times and then the engine stumbles to life when the cylinders are finally warmed from the slow cranking. It'd be nice if propane (or another gas/liquid) can help kick up the cranking speed / RPM, so we can tolerate lower compression for reliable high performance on street (we all know what happens to headgaskets with high compression...).
A fixed propane valve for brief starting could be used, no need for a throttling valve (my post wasn't discussing propane for power enhancement).
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Just a guess, but since Propane has a higher ignition temp, the diesel would have to ignite to get the propane to ignite. So how would this help a cold start? :?:
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Just a guess, but since Propane has a higher ignition temp, the diesel would have to ignite to get the propane to ignite. So how would this help a cold start? :?:
You're right, I re-read the propane facts and propane needs 100+ deg higher temp than regular diesel for ignition. Oh well, making 18:1 TD street-startable & practical is still wishful thinking :( :)
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Just a guess, but since Propane has a higher ignition temp, the diesel would have to ignite to get the propane to ignite. So how would this help a cold start? :?:
This is correct. No starting help here.
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Well as a actual starting aid, I guess you may be right.
After the first revolution of the engine, after it has actually started and is running, albeit like *** because either its cold as hell outside, or because you have a bad ass low compression motor, it is still making fire, right? I was thinking that if its burning diesel, than the burn would still light off the propane.
So my question is still kind of out there, but perhaps modified.
Could propane help in the cold or with a low CR motor once you get that motor to at least fire, and run even a little? When I lit the BBQ tonight, the propane fired off an almost dead match that I thought was out.
Would this smooth out the inital idle enough to make a difference?
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think of it this way... the propane assists the diesel in burning more efficiently right? if you left the GP's on, they *should* be hot enough to help ignite the propane...
unless someone has tried it or has experience with it, i wouldn't start saying that it is a wasted effort...
cheap and simple way of testing it out would be to have a little coleman propane tank at the intake.. would take 2 people to test it out. open the tank a little as the engine cranks... of course malone or someone with low cr and bad cold starting issues should try this to see if it makes a difference.
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How hot do the glow plugs get when they cycle? They look pretty freaking hot when you put the juice to them if you have one out to test it.
I get the difference in temp caused by compression. The compression temp alone ( 400?C ) will not be enough to ignite the propane/o2 mix wich has a ignition temp of 500?C. Diesel has a lower ignition temp, 385?C.
If diesel ignites at 385, and the propane is already at 400 from compression alone, and the propane mix raises the percentage of combustion efficiancy 15% ( 75% to 90%) than why would it not ignite when the diesel fires at 385?
Granted, a low CR motor will probably give you different compression temps. I dont know how to figure those out.
Still with a 15% increase in combustion efficiancy and a white hot glow plug, I don't see how it wouldnt combust.
(By the way, speaking of flames and ignition temps :twisted: :twisted: Has anyone ever seen the old time hotrods that had a sparkplug threaded into their exhaust near the tail pipe?? You dont want to tailgate one of those cars :!: :shock:
Sooo, if you had a small tank in your trunk, perhaps.......)
Here is the part of stewardc's post I am refering too:
Introducing LPG gas into the combustion air intake of a diesel engine acts as an accelerant, promoting the even burning of the diesel fuel, and more complete combustion, resulting in more power being produced. Many web pages and forum posts will call LPG a "catalyst" but this is not correct, as LPG creates no change in the molecular makeup of either the air or the diesel fuel.
Propane by itself will not self-ignite inside a diesel-fuel compression-ignition engine. During the compression stroke, the air/LPG mixture is compressed and the temperature is raised to about 400?C, not enough to ignite the LPG, which has an ignition temperature of about 500?C. When the diesel fuel is atomized into the cylinder under high pressure, it immediately self-ignites (diesel ignites at about 385?C.), and causes the LPG to burn as well. Since the LPG is in mixture with the air, the flame front from the diesel spreads more quickly, and more completely, including igniting the air/fuel mixture which is in contact with the cylinder walls, which are cool in comparison to the super-heated air inside the combustion chamber. Much of the cleaner burning of the fuel is attributed to this ignition against the "cooler" components of the engine, and accounts for raising the percentage of combustion from a typical 75% for a well-tuned diesel engine running on pure diesel fuel alone, to 85-90% with the addition of LPG.
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I get the difference in temp caused by compression. The compression temp alone ( 400?C ) will not be enough to ignite the propane/o2 mix wich has a ignition temp of 500?C. Diesel has a lower ignition temp, 385?C.
If diesel ignites at 385, and the propane is already at 400 from compression alone, and the propane mix raises the percentage of combustion efficiancy 15% ( 75% to 90%) than why would it not ignite when the diesel fires at 385?
If There are problems igniting the diesel reliably on a cold start, then you aren't even reaching 385 consistently, or it would be igniting. So occasionally the Propane will ignite, but only after the diesel does. Which doesn't help so much. Except maybe to raise engine temp a little faster.
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The nitrous route for the 1.6NA seems to be a great option, however, I wonder how long a bottle would last, with day to day driving.
I like the idea of the turbo pump and LDA to deliver nitrous at full throttle only, this would enable passing and hills, which are my biggest need.
If one wasn't a complete buffoon with the right foot, how long could one expect a bottle to last?
Also, why is a bottle opener required? Is it not safe to keep it open?
Thanks in advance, if this post is still being monitored and answered.
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i think id go thru a bottle every day or 2,cause i engage my water injection every time i floor it
if i did that with lol gas,,id be broke
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hmmmm you could probably hillfolk it and make your own nitrogen oxide like they did on myth busters :lol: probably take a few hours to fill a bottle though.
edit: hmmm fertilizer :)
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are you sayin to stick a cowpie next to my air filter???
oh snap,i just thought of a new idea
i better go patent that
itll be the latest rage with the kids
"what kinda dung are you runnin bro??that thing is fast!!!"
poppin the hood at cruise night:
"wow look he has the illegal pachyderm poo!!!!!" :roll: :lol: :lol: :lol: :lol:
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this has me thinking... what about just compressed oxygen??? i wonder if that would be illegal here in Canada too... only NO2 is illegal right?
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I've thought of that too. It would possibly be even more effective than nitrous. Way cheaper as well. It probably wouldn't cost more than about $10 to fill a tank the size you'd be running. A couple people I know say nitrous tanks are about $40-$50 to fill.
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I've too considered compressed o2 to be a cheap alternative to NO2.
Use a Diving tank and fill it to like 2,000 psi or something. :P
you could just bleed it into the intake anywhere. It would be an easy set up. You may need a license though to buy compressed o2.
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yea.. just get oxy acetylene without the acetylene :lol: