generally speaking the methanol is suppose to lower the a/f's. But I see where jeff is headed and it bears listening too.
The water will help with any detonation control as we know and by only running a 50% methanol water blend i wasnt too worried about it. Now when you start adding nitro----welll-----i dont know about that. Maybe Caution is a good word here?
Heck we have never tuned to gain full advantage of the water meth---and I do not want too Det control only for me.
olddragger

 

by lowering the a/f i mean a lower number---richer mix--just to clarify.
OD

 

Knowing the math and knowing practical application are two different things.

 

I think the wierd thing is that the combination of injection causes conflicting number's via AFR.

Just water injection will make your AFR's richer on the same tune - and make you lose some power. But you can get it back by adding timing and you CAN run leaner overall AFR's (ie. closer to 12.1 than 11.5).... of course if the water runs out; bad things will happen.

Then you add in nitro; methanol etc; and for me it totally monkey's up the works in my own mind! LOL

If you really wanted to take full advantage of all that stuff for power-sake; I think you need to read Baghdadi's timing paper (flame speed and fuel chemical make-up); in order to really work at optimum.

 

Well, what I began wondering which brought my entire understanding of the issue at hand into question was do wideband O2 sensors actually measure AFR or do they measure O2 concentration and then back that out to a known gasoline combustion ratio? Chemical processes including combustion have timelines and completion percentages. Mixing something 1 to 1 will not yield a pure result initially even if the stoich ratio is 1 to 1 because not every A will meet up with a B to react.

If that is so, can you really trust the AFR reading of a gauge used for gasoline engines when you are not in fact burning only gasoline? Maybe your AFR is just a representation of your lambda or deviation from gasoline stoich (14.7). If you were running pure alcohol only as a fuel and running dead on stoich for it, would your AFR gauge read 6.7 or would it read 14.6 because the mixture of stoich methanol should consume oxygen similarly to stoich gas.

Once I got to that point, I was glad I wasn't going to be running any non-gasoline fuel in my car and that my small brain could take a nap.

 

Effective AFR perhaps, but not actual.

No. That is part of my point.

 

Just to be complete; my references...

A Simulation Model for a Single Cylinder Four-Stroke Spark
Ignition Engine Fueled with Alternative Fuels
Maher A. R. Sadiq AL-BAGHDADI
Mechanical and Energy Department, Higher Institute of Mechanical Engineering,
Yefren-LIBYA

Internal Combustion Engine Fundamentals.
Heywood, J.B.
Massachusetts Institute of Technology
McGraw-Hill, 1989.

Theoretical investigation of flame propagation process in an SI engine running on
gasoline–ethanol blend
Hakan Bayraktar, Mechanical Engineering Department, Faculty of Engineering, Karadeniz Technical University, Turkey

 

WoW this thread just became to advanced for me. THANKS KANE

Well glad to see you pop in again

 

I out-nerded myself again huh? Sorry...

 

There he goes, foot-noting again...

 

Collaboration is important.

 

My latest update:
Running a 175 ml Snow perf nozzle into the MAF.
Using 1 gallon of Snow Boost-Juice per 3 oz of RC car Traxxas methanol/33%nitro-methane.
The RC car fuel turns the Boost-Juice opaque, bubble-gum pink, no separation has happened with this mixture.

I have boost juice seepage from the air filter; for this reason I cannot try the full straight methanol/nitro-methane mix.
(Straight methanol IS Flamable; never forget this)
My next plan is drilling the a hole for the injector into the engine side of the inter-cooler output to allow full strength methanol/nitro-methane use.

On the plus side, the straight methanol/nitro-methane RC fuel is cheaper than Boost-Juice

Waiting for the next dyno meet

 

uhhhh rote --do you have the w/m injector before or after the intercooler?
Be REAL careful with this stuff. Real careful.

On note we probably need to monitoring the egt's more so that the a/f's or lamda? Now some a/f gauges can be set to use a different fuel but not a blend of anytype.
olddragger
olddragger

 

I think you need to monitor both - just realize your target AFR is going to be different for your fuel mix; unless you JUST use it as a saftey net against detonation in which case you will likely make less power that straight gas.

On the EGT side; once you have your baseline EGT; then just watch for variations unless you want to tune a lot of timing changes (most likely on the dyno).

 

Now I am using 1 gallon of Snow Boost-Juice spiked with 3 oz of Traxxas RC car fuel.
With 128 fluid ounces in a gallon, and I am mixing in 3 ozs of the the 33% nitromethane flavor fuel, gives 1 oz of nitromethane per 128 oz of water methanol mix.
I have tested this mix and let it sit with no separation observed after two days.
My 175ml injector is in the MAF sensor housing, and that is causing the air filter seepage of the Boost-Juice mix.
I will move my injection point to right after the inter-cooler soon, then I can try straight methanol with the nitromethane.
I will start with methanol with "only" 5 or 10% nitromethane, and (maybe) work up from there.

Also, buy and use rubber gloves when handling methanol....


PS: I can faintly smell nitro in the exhaust when the Boost-Juice is running.....

 

I have tested the Morgan fuels RC car (Green) methanol 15% nitromethane fuel mixing 50/50 with distilled water with unsatisfactory results.
The oil settles out of suspension, it looks like a lave lamp in the bottom; I tried this brand due to the synthetic oil instead of the caster oil used in other RC fuel.
The Snow Boost Juice seems to mix fine with "small" amounts of higher nitromethane fuel, but turns a darker bubble gum color.
I have went as far as 3 oz of the 33% nitromethane fuel in a gallon of Boost Juice.

Yeah, the nitromethane "works" on the butt dyno real well...

 

sure sounds like you are having fun dude and it also sounds like you are being careful. remember the w/m system pump and filters are not made to handle any oil in the system. and be real careful of any possible "pooling".
Have you ever seen a top end blow? It aint pretty. just thoughts and concerns for a fellow car nut.
Kane thanks for the advice. I am running mine just for detonation insurance, but i do get a little more power from it probably due to the lower intake charge temps that are being produced. We have such long dang intake runners and so much radiant heat sources on this engine you just need something.
Oh by the way ---we soon will have the phenolic heat barrier intake gasket available!
and a note ---whoever said headers does not help this engine---lied!!
olddragger

 

Dey Denny
for what its worth....you seem like youre on a mission...and a good one to boot....i like your style and the way you communicate to the group....
with age, comes wisdom!!!

carry on mate!!

 

Denny,

Thank you for the concern, I probably will not go with much higher nitromethane mixes as this is all I need. (Till I get used to this power level )
Good info on the header, but I think whoever said that a header doesn't help was normally aspirated.
Heat barrier and intake/exhaust wrapping sounds great too.
Let me know when/if the heat barrier is ready for sale.

 

Would a sign of that be Boost Juice dripping from the air filter?


I need to move my injection point from my current MAF location, to the output from the inter-cooler, till then I think I will need to step down to a 100 ml (from my 175 ml).

 

Just got back from a dyno session at Delirium in Kissimmee. Ambient temperature 95 degrees and 53% humidity. First run I kept it below 8500 rpm due to the extreme heat conditions inside the dyno location. Notice only 231 whp at 8200 rpm. However 5 minutes later with 50/50 methanol bumped it to 283 whp at 8200 rpm. That is 50 more whp by spraying 50/50 methanol (100 ml before the blower and 60 ml after the intercooler). The third run was with my RC 33% Nitromethane mixture. Just one more whp. I’m going back to the dyno shop on the 3rd of August and hopefully I will have the Snow Nitro Boost that is on back order too see if it really does what Snow advertise. The pressure is on Snow. One more note: Although the dynojet graph illustrate @ 8600 rpm on the 2nd and 3rd run, I pushed the car past 9000 rpm based on the car rpm gauge. This is why I don’t like to use dyno numbers to compare with other cars but to rather see if MY CAR is making more whp.

 

You are right OD. See attached dyno (blue w/o header, red with header) and notice no only a 7 whp gain but notice that it took 2 less seconds to spool the engine to about the same rpm. That is the big difference between using the stock OEM exhaust manifold and a well manufactured header along with the SC. Now, I’m not even factoring what it will do in a ¼ mile but we will find out in August when Bastage and I (hopefully other SC owners) will take the cars to the track. This is why dynos are just one part of the equation and not a final power measuring statement.

 

Holy Be Jesus man--damn! Yes i would say that is good proof about the headers!
mine will be here Tuesday and I am going to install the modified lower intake with a heat barrier gasket all at once--the barrier gasket is not yet ready but soon---i hope.

found a new heat source guys.
that octopus thermostat housing with all those hoses attached puts off a hell of amount of heat. Cover those hoses and seal them from passing that heat on back to the intake and you will be pleasantly surprised. Hell it even lower the alternator temps!
olddragger

 

Actually, all that dyno says is that you moved your torque peak to a significantly lower RPM.
You may have picked up a bunch of power, by that dyno doesn't show it since you let off as soon as it peaked.

 

marsredr100 good stuff, thanks for posting up those dyno sheets. Are the majority of pettit owners finding that they need to run water/meth injection in order to see whp above 260whp? Also I assume you're spraying prior to the blower to help cool the blower? If that's the case, I would have expected the air/water cooling system to be able to take care of the blowers temperatures.

I understand the 95 degree heat can put a strain on the system. With the hot temperatures in Phoenix I'd hate to have to run the water/meth just to get around town.

Has Pettit made any plans to include a water/meth system with their kits?