my setup: t04b/msd 52lb, aeromotive fpr, warlbor 255, stock ignition, emanage ultimate.
plans and goals: 264 cams, arp head studs, multilayer head gasket. after that i want to put the boost to 18-20psi but using meth.
now form when i understand meth has a high octane rating, and when mixed with pump gas can lead to the octing rating to increase alot. also i hear that it cools down the intake charge leading to less hi temp in combustion chambers allowing for less chance of detination.
now if im running 11.7:1 on boost at 12 psi and i spray meth when full boost hits the a/f will drop down and become rich? right?. so i can ither lean it out a bit on boost but what i want to do is add some timing to try and pick up more power, now with spraying meth it will allow me to do this b/c it will lower the combustion temp. making chances of detination less allowing me to add timing to get more hp and torque. also it will richen up the a/f mix allowing me to use less fuel under boost. does my theory seem correct?
so now is spraying meth and boosting 20psi on stock internal seems safe? i mean the comperssion ration of the stock ka isnt bad, but whats the chances of messing the pistion up at such hi boost? also the rods will hold up?
does the seem pratical or am i asking for a blown motor?
Post Title: Re: methanol injection? (turbo2nr)
Posted by: VeloceDrift at 10:41 AM 5/19/2007
Yes, you would run a leaner AFR because you will not need extra fuel to help cool since you have methanol. But I suggest you do it in lambda. 12.5AFR it around .82lambda or something I forget...get a conversion chart. The reason for this is because lambda doesn't change or get thrown off when injecting different substances.
Nissanfanatic ran 20psi with 100 octane fine so methanol injection should be fine as well. Just make sure you have a good one.
As a side note, because methanol will prevent more knock and detonation..it will also resisit normal combustion as well. This is why more timing will give it more time to burn properly.
Post Title:
Posted by: turbo2nr at 5:38 PM 5/19/2007
i gues meth is a little more complicated then i taught
Post Title: Re: (turbo2nr)
Posted by: Craving4Boost at 10:33 PM 5/19/2007
Stick with adding boost for a power increase. I wouldn't go leaning the AFR's out either, since Meth requires almost double the amount as pump gas to reach stoich.
Keep the AFR's at or under 12.5 even while spraying meth. Just crank boost up 5psi or so. Your best bet would be a knock meter of some type. I used the MSD Knock Meter but that was on my Skyline, which was a far quieter engine.
Are you going to use a mutli staged kit? Or variable type? I've used both and recommend the variable, but a single stage kit is good for an additional 5 psi or so over pump gas.
WD
Post Title:
Posted by: turbo2nr at 10:04 AM 5/20/2007
i was planing to start spraying around 10 psi and hit peak at around 20psi is their a formula or some thing on how much meth is required per psi? or a ratio of meth to gas to be safe? some say 85% i believe?
wd- thanks for the helpful insite as always, i was too iffy on pulling less timing just incase, andi wasnt going to do more leand then 12.5 on boost, but using the meth will richen the a/f mix alot wount that casuse the car to feel sluggish b/c of the richness? when i was tunning the safc and it was running 10:1 on boost it felt soo slow, then when i leaned it out it felt soo much better. so i guess on meth im gona have to lean it out a bit to be safe?
im getting a knock lite soon. its on my to get list. know you said the variable worked better for you, im a newbie at this what is the difference between the variable and the staged kit? and why did the variable work better for you? and also i can only boost 5psi more safer with the meth? so if im tunned for 15psi on my map it would only be safe to boost 5more psi correct?
also with the timing retard so much will the meth combust fully ? or can i retard less timing up to when the meth is therE?
thanks for all the help
Post Title:
Posted by: WDRacing at 10:14 AM 5/20/2007
The variable kit is better because it allows the onset of meth to be gradual and increase as boost boost rises, rather then a single stage that just opens a valve or turns on an injector at one set volume. The single or staged setup will work fine though. A staged setup is simply setup like a single stage but with more injectors or valves being triggered as boost increases. Like having injector come on at say 12 psi, then another at 17 so you avoid the over rich condition.
With a single stage, you can run as much boost as you want, but you'll be running WAY rich until you reach the target boost level. A multi stage kit allows you to adjust the injection a little better then a single stg so you can add basically as much boost as you want. You just need to add more then one stg. For instance, I've seen a Chrysler Reliant run a 4 stg kit and break into the 10's.
Variable is the best because you avoid the multiple pressure switches and multiple injectors. Variable controllers either adjust pump voltage to increase spray volume or pulse the pump or solenoid on and off really fast.
There have been guys running 2 and 3 stg kits for years on everything from minivans to 10sec Grand Nationals.
Just as a note, try running E85 instead of meth, cheaper and almost as good of an octane rating.
Post Title: Re: (WDRacing)
Posted by: WDRacing at 11:14 AM 5/20/2007
this in addition to Brians link might be of help as well.
Post Title: Re: (turbo2nr)
Posted by: Craving4Boost at 5:35 PM 5/20/2007
Most people run a 50/50 water/methanol to have added octane increase with cooling effects.
I have ran 24psi on the dyno with 100 octane. I also ran that for about two months before I bought a new intercooler and lowered the boost to 20psi to make more power. The stock internals are strong if you do stuff right.
The one thing I would worry about on your setup is the ability of that turbine arrangement to flow. IDK how well the Revhard will flow, esp with an on center turbine housing. When you are pushing the edge, backpressure on the exhaust side can really keep the exhaust valves hot. Just as proportional to your hand touching something hot, the harder you press, the more energy that is absorbed. You do not want to stuff the exhaust valves full of energy in the form of heat and then stuff that cylinder full of air and fuel. This is the exact reason I do not try for more power on my car. Even with my Groundzero manifold, the T3 footprint+wastegate size just does not allow enough gas flow to keep the exhaust pressure down.
Ever notice not many of those T28 setups last very long when they begin to push around 300whp? The same applies to SR's. They are just more forgiving due to a low CR. If you want to run a huge compressor with a small *** turbine, you need to run a really big wastegate for the rest of that exhaust gas to exit the manifold.
Post Title:
Posted by: turbo2nr at 7:59 PM 5/20/2007
cory, the exhaust temp of the valves is a little confusing, are you sayin that with the revhard and my setup the gases wont be able to move out quick enuff adding more stress on the exhaust valves? or something to taht extent? so now using a bigger wastegate how will that help? and by bigger do you mean spring wise or acutal wastegate (btw im using a turbonetics 38mm evo wastegate) so in the end can this lead to some sort of valve failure in the head?
Post Title:
Posted by: WDRacing at 9:05 PM 5/20/2007
I suggest the same thing already mentioned, a 50mm wastegate will improve flow. I think you'll be ok though for the most part. Another great way to tune for meth injection is to use a EGT gauge. Get a target number while running without meth and then try to keep that same number while increasing boost and adding meth.
I'd run straight meth myself, or E85.
WD
Post Title: Re: (WDRacing)
Posted by: Craving4Boost at 9:54 PM 5/20/2007
I don't know what the weather is like over on the east coast so I guess everyone is different.
As for the exhaust issue, what else would help the problem? or are we just getting into forged internals and upgraded heads at this point...
Post Title: Re: (Craving4Boost)
Posted by: WDRacing at 6:17 AM 5/21/2007
The way I look at it is simple, if you just need to avoid knock because you maxed out the octane of pump gas then water is probably your best bet. Since a very small amount of water mist will cool a combustion charge 200* very quickly.
If you want to use meth as a fuel source in the top end because you've maxed out the injectors AND need more octane, then 100% meth is the best way to go. The only reason I started using meth a few years back was because I had maxed out my injectors and didn't want to buy a ROM tune for my Skyline. I had read that the GN guys had been using meth for years, so I gave it a go. I was able to run an additional 10psi of boost with the meth injection. The RB20 and RB25 intake manifold are perfect for running sub injection though since the TB enters the plenum in the center, it makes for a very even dispersal to all 6 cylinders. But I'm getting off track...Alcohol injection FTMFW
WD
Post Title:
Posted by: nissanfanatic at 9:40 AM 5/21/2007
I doubt you will be able to couple the revhard with a 50mm wastegate or even a 44mm. Don't buy one of those adapters from ATP either because a 44mm hole doesn't do any good if you have a 38mm wastegate runner tube. Measure it and see, but I don't think the revhard wastegate port is 44mm.
The only thing you can do to benefit this issue is to use larger turbine flanges and wastegates. We are basically fighting the age old backpressure. Hence why 1000whp supras aren't running T25 footprint turbos.
I mainly pointed this out to you "turbo2nr" because you run the on center T4 flange. I know from looking at that housing that it is not going to flow well at all. Basically, IMO, I recommend that you start looking into a better turbo/manifold setup before turning the boost up.
Post Title: Re: (nissanfanatic)
Posted by: turbo2nr at 10:30 AM 5/21/2007
i m leaning more towards a 50/50 water meth mix. im mainly concerned about cooling the cumbustion chambers, i have more then enough fuel . i want to hit 350-380whp with my cuttent setup and i dont plan to do this often. i just really want to shut my boy and his 450whp sti up on the hi way.. (i know that sounds a little ricer of me )
now i was reading the emanage ultimate and i can use up to 4 additional injector and control them via the emu. i think that would be my best bet to add in the meth gradually untill i hit peak around 18-20psi. i dont want to run super rich at lower boost levels (12psi) and i only need the meth to kick in after 15psi.
now how safe is it to inject the water in all the time on boost just to keep combustion temp down? any side affects?
Post Title: Re: (turbo2nr)
Posted by: Craving4Boost at 10:42 AM 5/21/2007
Also, good luck with your friends 450whp STI lol..im sure it will take more than 350-380qhp to beat it even if we are "lighter."
Post Title: Re: (Craving4Boost)
Posted by: WDRacing at 5:24 PM 5/21/2007
WD
Post Title:
Posted by: turbo2nr at 6:27 PM 5/21/2007
You will probably be lacking in the top end even with 380whp... I'd have to see his dyno chart to decide..
Post Title:
Posted by: Craving4Boost at 10:07 PM 5/21/2007
As for the STI, I would rather ride in the 380hp KA-T anyway. I don't care too much for cars that came factory turboed. The higher compression of NA cars is fun....
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