G-Teched my 1.6TD - Part 2

[VWRacer]

Yeah Alcohol, has even a higher energy per which ever unit you choose to use then diesel

Not so.

Gasoline has 19,000 to 20,000 BTU/lb
Diesel has 18,000 to 19,000 BTU/lb
Ethyl alcohol has 11,500 to 12,800 BTU/lb
Methyl alcohol has 8,600 to 9,700 BTU/lb

[malone]

I wonder why they haven't installed a 3,000HP+ diesel motor into a 1/4 dragster and blow the current 7 sec record away. It would be interesting.

[Master ACiD]

because of the rules.

also top fuel is putting out 5500hp.

[DVST8R]

Yeah Alcohol, has even a higher energy per which ever unit you choose to use then diesel

Not so.

Gasoline has 19,000 to 20,000 BTU/lb
Diesel has 18,000 to 19,000 BTU/lb
Ethyl alcohol has 11,500 to 12,800 BTU/lb
Methyl alcohol has 8,600 to 9,700 BTU/lb

VWRacer, Thank's for correcting me I obviously was under the wrong impression.


Mark, the reason that those motors are not in a drag car such as the one that i posted the link to is size and weight, tractor blocks for there displacement are huge and heavy, neither of which matter to a pulling tractor as the tractor has plenty of space, and you end up adding weights to the front end of the tractor anyway.

Master ACiD, The drag car mark refers too doesnt run in a sanctioned class therefore you could put a tractor motor in but for reasons I have already mentioned I don't thikn it owuld be an easy or worthwile task. Last I heard Top fuel aka: nitro methane guys where in the 6200Hp+ area. With that being said I like my diesel nice and safe and stable, Nitro is so sketchy :shock:

So I pose my next question: Why do alcohol tractors consistently make more power? they run the same motor's just converted to run alcohol, and produce alot more power, is it better cooling of the fuel ?? or .

[jackbombay]

So I pose my next question: Why do alcohol tractors consistently make more power? they run the same motor's just converted to run alcohol, and produce alot more power, is it better cooling of the fuel ?? or .

  Are they still compression ignition? If not they would be homognous charge engines and could spin higher RPMs with similar characteristics to a gasser.

[Master ACiD]

i have a theory that btu per gallon isnt an indication of power potential.
 for instance, you take a gasoline car engine, convert it to run on alchy, and you get 10% more power. how can this be? gasoline has more btu per gallon than alchy.

the reason, i think is the air to fuel ratio. alchy may not be quite as  high in btu value than gas, but you have to run more than  twice the ammount for the engine to run properly. roughly a 12:1 afr for gas, and 5:1 afr for alchy. by the way im talking about optimum power here, not stoich.

so inside the actual cylinders, it would look more like this.

btu of gas:20,000?
btu of alchy :  25,000?
diesel: somewhere in between?

i am not sure about diesel. i know that just like alchy, it has a lower afr than gasoline, if you ran diesel in a spark ignition engine. for instance, try running a 50% mix of diesel and 50% gasoline in a lawnmower, and the engine run run very lean and starve for fuel. need to run it with the choke on to keep it running.  if you richen up the carby on the mower engine, then you can run 50% diesel and 50% gas mix without lean issues.
pretty much the same thing happens when you try to run a gasoline engine on alcohol.

to put it all together and form a conclusion i am not really able to do. it starts to get foggy from ths point on out for me. like i said, its only my theory and i dont know if this is all true.

[RAMMSTEIN]

Got your PM.

Here is my attempt at Paint, straight up KG style.



The Red circle is the the exhuast valve, the Blue one is the intake valve, the grey area's on either side are the area that has been relived. Of coures in real life they have uniform shape and size, as well as, they have a slightly differn't overall shape, size, ect..., but it will give you guys an idea. As Dave said earlier the relief is about .25mm-.5mm deep.

Could you do this to a 1.6/1.5 NA?

More air flow, more fuel...you know. :wink:

120 hp 1.6D.... :twisted:

[DVST8R]

I'm sure you could, as it was oringinolly developed for NA gas motors.

[le mecano]

Picture by RedRotors[/img]

cool, the picture of the cuted head i give to redrotors!

i'm happy to see that it served to someone.

good works!

[jwspin]

the alcohol tractors run real clean, there was one alcohol tractor on our circuit this year and it was pretty amazing. no one voted for him to set the sled.

-jared

Yeah Alcohol, has even a higher energy per which ever unit you choose to use then diesel, as such the diesel guys are really starting to struggle to "keep up" with the monster alcohol guys these days. I'm still a sucker for a pro stock or pro mod diesel tractor though, I have loved them since I was knee high to a duck. :wink:

Jared where are you from? What pulling circut?

im from upstate ny, the ciruit is a northeast circuit. one of our big pulls is the washington county fair. it has been on espn before. i dont have a pulling tractor though i just help wrench on my friends.

-jared

[greyrabbit]

i have a theory that btu per gallon isnt an indication of power potential.
 for instance, you take a gasoline car engine, convert it to run on alchy, and you get 10% more power. how can this be? gasoline has more btu per gallon than alchy.

the reason, i think is the air to fuel ratio. alchy may not be quite as  high in btu value than gas, but you have to run more than  twice the ammount for the engine to run properly. roughly a 12:1 afr for gas, and 5:1 afr for alchy. by the way im talking about optimum power here, not stoich.

so inside the actual cylinders, it would look more like this.

btu of gas:20,000?
btu of alchy :  25,000?
diesel: somewhere in between?

i am not sure about diesel. i know that just like alchy, it has a lower afr than gasoline, if you ran diesel in a spark ignition engine. for instance, try running a 50% mix of diesel and 50% gasoline in a lawnmower, and the engine run run very lean and starve for fuel. need to run it with the choke on to keep it running.  if you richen up the carby on the mower engine, then you can run 50% diesel and 50% gas mix without lean issues.
pretty much the same thing happens when you try to run a gasoline engine on alcohol.

to put it all together and form a conclusion i am not really able to do. it starts to get foggy from ths point on out for me. like i said, its only my theory and i dont know if this is all true.

I think you've got the heart of the issue -- the amount of air needed.  Horsepower scales with rpm ... I think the F1 guys are running at 18,000 rpm redlines ... dragsters well over 10,000 rpm.  At those rpms getting enough air in is tough even with super or turbo charging.  With alky you need less air and you get a get a better/quicker cooling effect on the inlet charge as the alcohol gasifies.  

As long as we're talking "normal" rpm levels the torque advantage of diesels translates directly into a power advantage.  Things change when race engines get built for really high rpms -- at the limit rpm wins.  Years ago Toyota demo'd a small single cylinder gasser at 90,000 rpm just to show they could do it ... great specific power but tiny.  For me if you want to set the specific power standard with a diesel you've got to make the thing really spin.  I don't see any reason why this can't be done.  I do know (having blown up a gasser or two in the early 60's!) that pre-ignition/detonation is a huge problem in that world...this gives diesels a leg up to start with.  I've heard remarks about the relative speed of the flame front but haven't seen numbers besides nobody says a cylinder can only have a single fuel injector ... as for the pumps my daily driven is an old 6.9 l IDI ford with a stanadyne rotary pump very similar to the Bosch pumps on our VWs.  My truck revs to 3600 no problem...now that's a V8 so the pump makes 8 pulses per revolution and they are big pulses feeding 6.9 liters of displacement.  This is a bone stock pump.  Seems like getting 4 smaller volume pulses per revolution at twice the speed shouldn't be impossible ... (that's the same number of pulses per unit time) ... well that's 7200 rpm a nice step in the right direction.  Anyway you guys are the experts ... it's been nearly 40 years since I hot rodded an engine (still subscribe to Hot Rod though) ... but it's great fun to listen in on your discussions ... thought I'd chime in for the holidays.

All the best.

[fspGTD]

Fuels which are "pure hydrocarbons" (like gasoline, diesel, methane, propane, etc) must get all of their oxygen used in combustion from the air.  Alcohol however has oxygen stored inside its molecules, so more fuel can be burned for a given amont of air.  This is the primary reason why alcohol runs with a lower air to fuel ratio and also why it makes more power (for a given quantity of air) than a pure hydrocarbon fuel.  To read more along these lines, I recommend the book "High Performance Automotive Fuels & Fluids" by Jeff Hartmann.

[zyewdall]

Fuels which are "pure hydrocarbons" (like gasoline, diesel, methane, propane, etc) must get all of their oxygen used in combustion from the air.  Alcohol however has oxygen stored inside its molecules, so more fuel can be burned for a given amont of air.  This explains the primary reason why alcohol uses lower air to fuel ratios and also why it generally makes more power than a pure hydrocarbon fuel as well.

Hmmm.  I wonder how this affects biodiesel, since it is oxygenated as well.  I'd guess that is why it reduces smoke, since the engine is effectively running at a little lower fueling level for a given injection charge as far as the fuel-air ratio goes.

[malone]

I posted this on November 10 '05 in page 3 of this thread:

I failed Aircare (emissions) a few days ago due to excess white smoke during an idle test (hardcore revving in neutral). The criteria to pass is 0-30% exhaust opacity. The average of all passing diesels is 6%. I got 49%.

I went back to Aircare for the second time a few days ago and passed:



My car went from being a disgusting smoker (49% smoke opacity) to one of the cleanest diesels I have ever driven (2.69% smoke opacity). Both results were with regular diesel. And what did we do to make the significant change in smoke? Nothing but drive. During my first Aircare attempt the engine had less than 1,000km if I remember correctly. Right now it's probably around 6,000km. The engine just needed to be broken in.

Since the first Aircare attempt 935racer removed the head, had the prechamber cups ceramic coated, and installed a slightly thinner 1-hole headgasket vs. the 3-hole I had earlier. It was an attempt to increase compression/heat. The smoke since these changes were not any better, probably worse. We also swapped out the IP for a different one with no positive results. However, after driving a few thousand kms the smoke started dropping quickly. The shudder during low load at low RPM is virtually gone now. The engine purrs like a kitten and pulls very smoothly. It's like a whole new engine again, such a pleasure to drive :cool: It feels like I have a bit more power as well, or it could be placebo effect. My average EGT has dropped ~100 degrees F (pre-turbo) to 700-800 while cruising on the level highway @ 100km/h (approx 2,400 RPM tall gear, 2600lb load). Idle EGT seems to drop a little more quickly, usually to a minimum of 340 degrees F unless I idle for a long time.

935racer laid out a few injectors:











935racer installed the complete MB 300D injectors in my 1.6TD and I went out for a test drive. I had shudder during low RPM but it turned out that one of the injector lines were loose. After tightening I went out for a drive again and it was smooth just like the factory VW TD injectors. It was dark outside and I do not have a speedometer so it was hard to tell if I got a performance gain.. but it seemed I picked up speed more quickly at the top of 3rd and 4th gear.

Seeing as 300D tuning is quite popular in Europe with some 500+hp results I wonder if they have upgraded nozzles. If they do, I'm sure it will fit in a VW TD.

I'm curious as to know how to run the GM 6.2L nozzles.. they do not seat properly in VW TD injector bodies. Any suggestions?

Eventually I will post a new "nozzle shoot-out" thread that details tests of the following injectors, done over a single weekend. Each injector set will be Gteched multiple times on a same stretch of road:

1) VW OEM injector set (1,000km new, 155 bar)
2) VW GTD aftermarket set #1 (160 bar)
3) VW GTD aftermarket set #2 (155 bar)
4) MB 3.0L 300D set #1 (130 bar)
5) MB 3.0L 300D set #2 (155 bar)
6) MB 3.0L 300D aftermarket (?)
7) GM 6.2L (?)
8) vwmike's 2mm opening nozzles (?)

Note that the MB injectors have 3 small ports at the top vs. VW's 1 big port (where the IP injector line attaches to). I wonder if there will be a difference with MB nozzles in VW TD injector cores.

Injector flame test







It's an amusing way of seeing which injector has the biggest and most intensive spray.

The 130bar MB 3.0L injector sprays a bit longer than the VW 1.6TD injectors. I would have taken more detailed pictures of each injector's flame if it weren't for a dying camera battery.

935racer (Dave) will have a comprehensive guide to governor modding with pictures covering every step. Here's a teaser pic... there will be better lighting in pictures for the actual guide:


We were actually going to finish it on Monday but my camera's battery died so we aborted it. We'll finish it this week. The guide will follow in a few days, at the latest next week.

[fspGTD]

Interesting flame test  :lol:  ...Makes for a cool pic!

Those Benz injectors look like "CHIP" center hole in pintle nozzles.  Are they DN0 SD 240?  Those have higher lift, as documented in the nozzle pintle lift comparison thread here:
http://www.vwdiesel.net/phpBB/viewtopic.php?t=2029&start=8
And there is more info on them here:
http://www.vwdiesel.net/phpBB/viewtopic.php?t=2230
Supposedly if you look really close at the fat pintle tip, it should have a tiny hole drilled down the middle and then another hole drilled sideways connecting to it.  The CHIP feature is for pilot injection, and the injector has been superceeded to different styles of pilot injection nozzles more like our vw "throttling pintle" design due to the CHIP having problems getting easily clogged with carbon.  Supposedly the CHIP injector bodies have a filter incorporated in them (as an added measure to keep the CHIP from clogging...) that may explain those different looking holes under the fuel supply unions compared to a standard injector body.  Neither their flow not their in-car performance on a VW application has been tested, so I'm very interested in hearing how your test results pan out.

I'm all set up and willing to flow-test injector nozzles (at full pintle lift) if anyone's interested, it would be a much easier method of testing a lot of injectors than swapping them onto the car and dyno testing each.  From the flow test results we'd have better information as to which injectors are worthy of the time and effort needed to to accurate, scientific in-car testing.  The flow test results would also be quite precise and repeatable.  Just a thought, and an offer.