|Topic Review (Newest First)|
|May 18th, 2017 10:06 PM|
|RDY4WAR||It's not taking stress off the engine, only off the turbo. If the engine is making more power, it's under more stress. Remember that boost pressure only measures what's backed up against the intake valves. When the valve opens, the pressure in the runner falls to near even with the draw of the cylinder with high velocity. The intake valve closes long before actual boost pressure is realized in the cylinder. This is why bigger turbo specific cams like that show more power with less boost. More is reaching the cylinder with less getting backed up against a closed valve.|
|May 18th, 2017 07:22 PM|
Originally Posted by mellis View Post
What size turbo are you running? If it's a 67 or a 70, I recommend getting a stage 1 or stage 2 turbo cam. (Depending on the spevs of course) and it will improve power gains in a useable power range under the curve.. My on3 67bb with the CMS stage 2 cams produced 601rwtq at 4300 rpm And peaked 540 rwhp at around 5600 rpm. Didn't have to rev it out to make great power. Takes stress off of the motor by running less boost to make the same power.
|May 18th, 2017 03:33 PM|
Originally Posted by sneaky98gt View Post
The Focus, like the Mustang, has no way of knowing if the meth is spraying or not. I used a failsafe device that required a WOT signal and meth solenoid signal. It would allow the meth spray without being WOT (since meth sprayed based on boost pressure) but not the other way around. If WOT was detected but no meth signal detected, it would kill the ignition to save the engine. I never had an issue with my AIS pump so I never had to use it. Nice thing to have though.
I tested a lot of different mixtures in various positions. I didn't see much difference in IATs between straight water and straight meth, (with appropriate and respectively sized nozzles) but I also didn't have to cool very much with the mixture either since I had the FMIC. I gained more and more power the more meth I sprayed though. While it is true that water draws out more heat, it also displaces the air in the charge piping and the cylinder. It absorbs the heat and holds onto it.
Water (H2O) has a very strong bond. While it only takes 212*F to turn it into a gas (steam), it takes extremely high heat (over 5,400*F) before it's molecular structure begins to break apart. Considering even nitromethane only reaches 4,350*F adiabatic flame temperature, you're not going to be able to break the water's bond in the cylinder. It passes right out the exhaust as steam.
Methanol (CH3OH) has an auto-ignition temperature of just under 900*F. The molecular structure breaks apart, oxygen and carbon are released into the chamber and accelerate the flame front. The heat that was captured in the charge piping gets released in the chamber. Another advantage is that methanol is considerably lighter than water by more than 20%, and also evaporates at a much lower temperature of just 148*F. If the air in the charge piping is above 148*F, the methanol boils and becomes a gas suspended in the air. This is why methanol works so well when sprayed pre-compressor because it will evaporate in the compressor housing, becoming fully suspended in the air, preventing heat from building up to begin with. Water, on the hand, will pass through the compressor housing as a liquid, clinging to parts, and more likely to cause erosion.
What I found to work best was 80% meth / 20% water by volume. This seemed to create a pretty good mix of heat reduction and octane boost.
In a car that's already running compression through the floor such as an SRT-4, more water will probably work better as the methanol will be of much less use. Same goes for a non-intercooled car that needs to bring temperatures way down. The higher the compression and combustion pressure, the more the methanol will shine.
|May 18th, 2017 02:30 PM|
Originally Posted by RDY4WAR View Post
The problem with your direction overall is the risk. I don't know about the Focus, but on our Mustangs, the factory ECU doesn't have any way to know if the meth is spraying or not. If you tune it to take advantage of the meth (i.e. leaning it out and/or advancing the timing), and then you have a meth system failure, your computer doesn't know that the meth isn't spraying any more. And therefore, you wind up with a whole lot of timing, nowhere near enough fuel, and nowhere near enough octane. Boom. It's a HUGE gamble.
Tuning it via the IATs negates that risk. You only increase the timing if the IATs dip below what you know they'd be without meth. And the only way they dip below those known temps is if the water/meth is on. Therefore, the ECU has valid feedback on whether or not the meth system is working, and as long as it's tuned properly, it will be completely safe, even in the event of a failure.
Doing it this way obviously requires a decent sized dip in IATs when the meth is spraying; if the dip isn't big enough, it's hard to distinguish whether the dip is from the water/meth, or if it's from something else like cooler atmospheric temps. This is why I normally recommend more water than meth (~75 / 25), as the water has a much higher heating capacity than meth, and thus will absorb more heat, and result in a bigger change in temps. I ran 23-24 degrees of timing at 9.7:1 compression with a non-intercooled Eaton at 12-13 pounds, with absolutely no detonation, with washer fluid, which is about 75 / 25 water/meth.
Likewise, this is why I say it may not be worth it on an intercooled centri or turbo setup where the IATs are already decently in check. The water/meth may not cause enough of a dip to safely and confidently add any timing into the tune.
You're definitely right about the advantages of water/meth at the line. With my old SVO setup, I had a manual override button to spray the meth; I'd spray it a good bit during the burnout, and then I'd give it some short pulses once I was on the line and up on the converter. It did wonders for cooling the IATs off the line.
|May 18th, 2017 12:42 PM|
Originally Posted by Snorky View Post
I'll be keeping the boost low for now so I've decided to hold off for now with the METH. I have e85 in my area so i think that will be a better option in the long run when the time comes! It will be a weekend/niceday/street car with maybe a once a year visit to the track so i think meth wont really be worth it for my situation.
Thanks for all the help guys! You all rule!
|May 18th, 2017 10:12 AM|
What sneaky is talking about is why I recommend more meth than water. With an intercooler system with IATs already under 150°F, use it as fuel instead of cooling. On my Focus, at 12psi the intercooler got the temps down to 120-130°F range on a 90-100°F ambient day. Spraying a higher percentage of cold meth pre-turbo brought my IATs down even below ambient to 65-70°F but more importantly was able to give it 6 degrees more spark advance.
My big problem was at the starting line after the burnout and when I'd be on the 2-step, the engine was burning down at 180-200°F IATs with 8-9psi built up. That's the flaw with a FMIC. If there's no air moving through it, it's not doing shit. I wouldn't start to see the IATs budge off that temp until about the 330ft mark. It would be 150-160°F at the 1/8th and drop significantly down to 110-120°F by the 1/4 mile but then the race is over.
Meth solved that problem. I could hold the 2-step all day long and the temps never go over 100°F. At the 1/8, 65-70°F. At the 1/4, 70-75°F. (The warmer ambient air passing through the FMIC was actually heating the charge back up at that point.) I'd take gallon jugs and fill them with 4 parts M1 meth with 1 part distilled water. Then I'd put them in the deep freezer for storage. With that much meth, it's not gonna freeze. When I go to the track, I'd put 3 gallons in a chest full of ice. It made a big difference.
|May 18th, 2017 09:08 AM|
The only way that you will (safely) see any power gains is if the water/meth brings a significant decrease in your intake temps. With a my old non-intercooled SVO setup, the IATs were out of control without water/meth, pegging the sensor at 254 F. A healthy dose of water/meth brings that down to the 100-120 range. Timing goes from 10-12 degrees max to 21-23 degrees max, and the car picks up 80+ horsepower (documented 8-9 mph in the 1/4). That's definitely a nice gain!
However, With an intercooled centri or turbo setup, as long as the boost levels aren't ridiculous (20+ psi), I think your IATs will be held decently in check without the water/meth, and thus water/meth isn't going to bring them down a whole lot. In other words, if your intercooler is already keeping temps at only 20 degrees over ambient (or whatever), water/meth isn't going to significantly decrease that. And since the temps won't be decreasing a whole lot, you can't safely add much timing.
There are plenty of people who will advocate for running a heavier methanol percentage setup, and just increase the timing anyway (without regards to the change in IATs) given the octane of the methanol. I advocate that this is a surefire way to grenade a motor. Been there, done that.
My opinion: if you're running an intercooled turbo or centri setup (or any setup really where your IATs are decently held in check), spend the money on upgrading your fuel system to run E-85 instead of going for water/meth. The cost is roughly the same as a good water/meth kit, power gains are similar or greater, it's a LOT easier to tune (re: a lot SAFER considering how many tuners don't know how to tune water/meth), and way less complexity.
|May 17th, 2017 05:13 PM|
Originally Posted by mellis View Post
60#injectors would have better street manners, and they will cover the power. I would run a KB boost a pump with your 320 pump for when you dip into the 500whp range.. If you choose this route, PM me. I have one for sale.
The question is will you experience any predet once you go over 10 psi? Will your compression ratio push boost be too hot? Meth isn't necessarily a bad idea.
What turbo are you running? I recommend if you are upgrading your valve springs you put a set of turbo cams in that are suited to your turbo size/spool characteristics. You may make your end goals with a few less psi.
|May 16th, 2017 03:45 PM|
|Enzian||Meth? Not even once.|
|May 15th, 2017 08:29 PM|
|Dassar||Sure, then you could add a little more timing into it. I run the devilsown kit with a progressive controller and have no complaints|
|May 15th, 2017 06:47 PM|
|NickPohlAandP||Heisenberg says YES to meth!!!|
|May 15th, 2017 04:31 PM|
|RDY4WAR||Meth wouldn't hurt but give it more meth than water. I found that 80% meth / 20% water gave the best results. A single nozzle set to come on at 6psi or higher will do fine.|
|May 15th, 2017 03:44 PM|
Should i meth?
Hello all. Long time since my last post about blowing my stock motor. Since then i have completed a 10.5:1 compression built motor and that will be accompanied by an on3 turbo system and stock PI heads with upgraded springs.. I will be running 93 octane gas, so my question is should i add meth? I only plan on running the stock wastegate pressure for now, which is around 8lbs or so. If the car makes 500/500 i will be pumped with that until i can get used to the new setup. It will also only have a 320lph pump, stock fuel lines and 80lb injectors. I'm not sure what the car will make when it's all said and done, but it's built to handle more than that.
What do you guys think?