this is my current dd.


the 240 was my dd up until about 6 months ago. i have a 2000 jetta that was just a weekend car but has now become my dd. i hope that will change soon though because i rather be driving my 240. that will hopefully change within the next month or so once i get my 240 finalized. the major set back i've had ever since i bought the car is that in don't have a garage to work in and only have time for repairs and what not on saturdays (sometimes).

 

i'd like to hear more about this biodiesel mix of yours. i don't really see how this would do any good . although gas and diesel engines are both internal combustion they operate on different principals, so could you clarify the confusion.

 

To clarify the confusion.

When you look at the characteristics of vegetable biomass bio diesel it has a cetane rating at about 46 to 52 Cetane, and animal based bio diesel has a cetane of 56 to 60 cetane and this depends on the ASTM manufactured process of biodiesel. Hard crude diesel normally has a cetane range of about 40~50 cetane depending if it is diesel manufactured 1, or diesel manufactured 2.

What does Cetane have to do with the gasoline ignition engine?

Well really nothing it is just a base to describe it's ignitable characteristics.

Cetane is the measure of which it has ignition delay, the lower the cetane number the more ignition delay that reacts to in the compression process. This means that bio diesel is more reactive to ignition and combustion than how regular petrolem based diesel fuels react.

Now unlike regular petro diesel, bio mass diesel is extremely high in oxygen just as gasoline is. Bio mass diesel tends to have close to similar ignitable properties to gasoline unlike petroleum based diesel.


Now looking at LHV (Latent Heat Value), Bio diesel burns slower than what gasoline does so it's exhaust gas temperature will be much higher than gasoline. Also the fact that it burns slower gives it a higher measure in Octane when ran through the ignition engine. This means that measured in KJ, or BTU bio mass diesel is very high in energy unlike ethanol.

Using small amounts of biodiesel can increase cylinder pressure just as a high KJ octane rated gasoline will do, this can in fact raise MPG, without effecting performance.

Downside to bio diesel is that it cannot be used in large amounts passed 10% in an ignition engine system. To much bio mass diesel will cause nitrile injectors to corrode and coagulate. It become apparent that it does damage to catylitic converters as it's Latent heat Value is much higher than that of gasoline and will burn out the catylitic converter. It does have draw backs if used in large amounts. But unlike ethanol it will not corrode aluminum or most metals used on the engine or cylinder head.

Now in the muscle car era and still sometimes used today. People will tend to add petro diesel to high compression ignition engines that are in the high 13.1:1 CR's if there isn't suitable leaded gasoline to use. It is a measure to prevent knock and ping, without losing the performance of gasoline.

In some respect biodiesel is better since it is enriched with oxygen it doesn't need a really high compression to even start it's ignitable combustion process. When blended to regular gasoline it will have the tendency to ignite upon spark ignition.

 

so to truly benefit from the bio diesels properties you would have to run higher octane fuel or risk detonation. knowing that the cylinder pressure and temp will be considerably higher is enough to discourage me from trying it. i'd have to image that the valves life span would be shortened considerably. not to mention that the pistons and rings would also suffer.

although i will look into the toluene and xylene both are about $15-$18 a gallon at most stores here. i have some friends that are painters and could probably get it cheaper so i'll ask one of them tomarrow.

 

If you have a white cap construction outlet where you live you can get toulene or xylene for as low as $11.00 a gallon, but you would have to buy 5 gallons just to get it that low.... So thats about $55 for 5 gallons of 117~119 Octane, where as 5 gallons sonoco racing fuel 100 octane for $65....
You can try torco racing blend but when I started looking at the cost it's just way to expensive for 104 octane. I think shipped the torco comes out to about $85.00.

I must warn you with toluene and xylene that you should wear a mask and gloves. As an inhalant, or absorbed through the skin it can make you very sick, it's also very carcinogenic until it blends and bonds with gasoline..

As far as the bio diesel, 4% mixture is safe. Once the mixture is more towards 8%~12% it becomes dangerous for an engine. But 4% is safe enough to mix with 89 octane with your SOHC compression of 9.0:1, or 91 Octane for my DOHC at 9.5:1.....

 

so this friday i went on an all day road trip across state to tend to some business. i must have got some bad gas in my jetta because it began to ping at times. i mixed a gallon of xylene with half a quart of atf and then poured 12oz of it into the tank. i used only 12oz because that's about the size of the octane booster bottles sold at the stores. that and righ now i wanted to know how much or rather how little i could get away with and eliminate the pinging.

the 12oz did the trick but more importantly i met up with a friend of the family who is working at a sherman williams store and is about to be made a manager. so once i get to using greater quantities i'll have someone who can get me the chemicals even cheaper. the problem is like i said, he's across the state.

 

those jetta wheels are nasty. lol jk

sohc ftw.!! lol

 

LOL, it's almost like the prohibition days, but instead your smuggling xylene and toulene for your gas tank.........
Random factoids from my local forum archives....
http://bayarea240sx.com/index.php?showtopic=474&st=0

 

hey vinnie, would the increased air flow from going KA-T make that biodiesel mix unusable?

 

NO....
It should actually increase spool time since it raises EGT's.

 

kthnx

 

today was a rather eventful day since i got around to altering the exhaust. about 4 years ago i had the magnaflow muffler removed and had something quieter installed instead.


the new 2.5" replacement

the 1.75" outlet of the old muffler is kind of restricting but defiantly quieter.



i had exhaust pipe replaced when the magnaflow was remover but they used a 2" pipe and not 2.5" like i though they would. rather than redoing it all with 2.5" i left it 2" but added a reducer to increase it to 2.5" toward the back.





i had this formed at a near by shop for $5


the finished product


i thought of painting it with some hi temp vht enamel but you can see how well that worked on the old muffler.

 

I think that looks SO much better man... Also how does that sound

 

it's not as quiet as i'd like it to be so i'll be adding a resonator sometime in the near future. it's not a raspy loud either but a more of a muscle car roar so it's not bad.

 

oh yeah if anyone knows of a good, fairly cheap resonator i'd appreciate it if you'd let me know thanks.