http://www.turbofast.com.au/racefuel13.html
Play at your own risk !!

 

Very interesting stuff. I'd probably still do a Meth injection kit instead. But I never really tought about adding it right into the fuel

 

That's a good idea. Acetone, toluene, MMT and xylene have all been used in blends to build octane. It's an old school trick that works and works pretty well. One area of concern using an aromatic hydrocarbon additive however is increased sooting. All tend to cause more sooting that can plug the O2 sensor over time, and can increase carbon accumulation in the oil. Acetone appears to cause the least accumulation, but methanol stills burns much more cleanly by comparison.

 

Just to reply to previous post I get m1 about 5 $ a gallon

 

So running meth will increase the need for more frequent oil changes?

 

I've decreased my oil change interval from 4k-5k miles to 3k-4k miles. I figure if there's blow by of the alcohol it will start to breakdown the oil. I'm really not sure if it's a legit concern but it's not a large expense so why not.

 

I want to say I payed $17 for 4 gal of M1 right off the VP truck last month.

I don't think the meth injection kits spray enough to be a power adder per say. My reasoning is my AFR don't change much while spraying. I'm not tuned for it either and my reading isn't with an aftermarket wideband, I could be off in my thinking. The intake temps definitely drop though. From the little reading I've don't to use methanol as a fuel you'd be looking for around 7:1 AFR, so you'd need to have quiet a lot running through the system.

 

Good questions and there's several good threads here on the subject. For answers we have to step back in time a bit though. Water injection was first developed in the 1880's, but lay dormant until the 1940's when Pratt & Whitney, which produced supercharged aircraft engines began experimenting with it. They discovered that by using water injection, they could get 20% to 30% more power out of an engine than by running it richer alone. Engines of that size (1340 to 2800 cu.in.) can tolerate water injection well. In addition those engine had a bore and stroke of approx 5.75" each, a compression ratio of 6.75:1, dual ignition systems and operated at 2700 RPM.

Unfortunately, water freezes in cold temperatures and high altitude, so Pratt & Whitney began experimenting with water/alcohol mixtures wherein the alcohol acted as an anti-freeze. Pratt quickly realized that the alcohol injected also increased performance. Pratt finally settled on a 50/50 mix of water and wood alcohol for optimum performance. Fast forward to today and many still use the same ratio with great results. For our application however, we have additional extenuating circumstances to consider.

1. The intake charge is compressed into a much smaller area (16:1 effective compression or higher).
2. The engine we use is considerably smaller (98 cu.in versus 2800 cu.in)
3. We use a single ignition system with a spark gap of .022"

None of the above is conducive to having high concentrations of a non-flammable liquid suspended in the intake charge. Performance can suffer when the high concentrations of water, snuff out the flame kernel before it has time to spread. Empirical evidence indicates a mixture of 80/20 meth/water by weight, or higher produces the best results in our engines. My personal preference is to run it pure for three reasons.

1. Methanol is an organic solvent and in pure form will do a better job of removing carbon deposits from the intake valves than when diluted.
2. Methanol is hygroscopic by nature and absorbs water from the atmosphere so why add more (Note: make sure you seal your storage containers well).
3. I'm lazy and don't feel like dealing with the hassle of mixing it 80/20 by weight

 

I was leaning more towards to 100% mix. Im glad you just confirmed. Thanks for the info tigger. Greatly appreciated.
Can you help me out understanding some chemistry a tick further now, you know i run sprintcars. I have the ability to obtain some crazy fuels so what would you think to expect if an M5 alcohol which has top lube, an oil to be seals good and pliable, and an amount of nitro in it. All pre-mixed by vp of course. What might we or i expect by running that fuel which creates alot of heat and is tough to ignite compared to say gas and straight methanol.

 

If your using an Aquamist system never contaminate your methanol with hydrocarbons in any way. Both Tiger and I have learnt that the hard way!

 

Nitro is a hydrocarbon ?
Since I've used it in the racecar, and the butt dyno pegged out. By me asking all the questions about, you can only guess whats on my mind. Lmfao

 

I would not recommend it as your timing advance and AFR with the Manic tune will be off. The combustive additives increase flame speed in the combustion chamber which means more power but less timing is needed. In our application, a slower flame speed allows you to begin the combustion cycle earlier on in the compression stroke, with less chance of detonation. This results in increased torque, and since HP is derived from torque and RPM, your HP goes up. When setting timing in a tune for a given fuel you begin with baseline timing levels, then advance the timing until no further performance increase occurs, then generally back it off about two degrees.

In addition VP's data indicates that when switching from M1 to M3, or M5, re-jetting may be required when running very rich, or the engine may stumble off the line. In other words these fuels have different vaporization points which can affect volumetric efficiency. Based on the variables these would introduce, I would not recommend adding a faster burning methanol mixture, without specific tuning to take advantage of it.

 

GOTCHA !!! Thats the explanation i was looking for. Thanks TIGGER

 

Do our N14 motors and ecus have variable valve timing (camshaft) in addition to being able to change ignition timing?

 

My understanding is the intake cam has variable timing but not the exhaust cam on the N14, but I may be wrong.

 

Thanks for the info...

 

+1
In addition variable valve timing on the exhaust cam has a very small impact on performance as compared to the intake cam. Think I have an N55 spreadsheet somewhere denoting the output difference. Both cams were fixed in the tune then altered individually for max performance, and then together. It makes for interesting reading so I'll see if I can scrounge it up and post it.

 

That would be a great read, thanks Tiigger.

 

I couldn't find the two files with one cam fixed. Found these for the N54 though with different degrees of advance on both. Might be worth looking at. Also found another file (N5X Tuning) Justin put together with some help from V8Bait off of one of the BMW forums. Good explanation with regards to vanos tuning, when your first trying to wrap your head around the maps since intake and exhaust advance/retard work backwards to each other.

https://dl.dropboxusercontent.com/u/...%20tuning.xlsx

 

Mr tigger, i have another technical question for ya. In the old school days of muscle cars and some modern ones, when a cam is installed we degree'd the cam to a specific intake centerline. What do you think the chances are of doing this to our motors. N14 and or the N18 ? Or do you think the ecu would have a fit if the cams or cam was advanced or retarded based on the application being used.

 

I would think the ECU would have to be told that you mechanically degreed it. In other words...you would have to accommodate the ecu settings for the degreeing.

 

Ideally yes. You'd want to adjust your tip in to take best advantage of it. The question is whether or not it would be worth it. If I remember correctly, exhaust only vanos adjustments on the N55 were only good for about a 3 to 5 HP difference. When you consider all the work entailed, I'd have to say no.

 

If I was running a Quarter Mile Drag Car at 100% throttle the few percent would probably be worth the trouble. Since my personal daily driver is a stock S with the JCW Tuning Kit ...I'm happy...for now...
When I build a 300HP motor with beefed lower end and upgraded automatic trans...that's a different story...
Just wanted to get a good explanation for the ones out there that needed to know. Thanks again for your expert knowledge...I couldn't have explained it as well as you...

 

Just realized I left off an important tidbit from my last post. The ONLY one I would even consider it on is the N14 exhaust cam. N14 intake cam and the N18 would be a big no-no. You'll get error codes as the ECU tried to compensate for what the position sensor is telling it.

 

Shoot me in the foot for picking a very basic thing (and way off topic) to talk about... but I've seen mixed numbers on this gap. I've seen your number of .022" but I've also seen .018". Is this a difference between N14 to N18? Or tuned and not tuned? Or is it simply misinformation? I have copper plugs and I want to check my gap as its been a few thousand miles now. I want to make shure I don't need to adjust them.