I have my car running well on 8-10# boost. Street manners are great and making good power. I am looking to turn the boost up to 15-18#. I have upgraded to 80# injectors and ordered a meth kit. I plan to run 100% meth.

My question is do you prefer to setup a good tune adding boost until you run out of fuel and then start adding boost? Or do you setup your max boost/fuel and use meth to cool the charge / prevent knock? I have searched a lot on this site but have not crossed a good thread on tuning with meth. Let me know what works for you on your setup.

 

Set the meth to come on at 8-10 psi and tune from there. If you have the meth kit, no reason to not have it on. Don't tune to the limits of gas and then add meth and retune.

 

Two thoughts:
Safe - Tune your setup without meth to a nice safe happy number. Add a small amount of meth on top to bring down temps. Do NOT retune fuel or timing with the meth. You will probably be .5-1.0 richer on the gas air fuel scale.

Aggressive - Tune it to the ragged edge on gas. Add meth. Add timing. Pull gas out of tune and continue to add meth and timing until it stops gaining power. Blow it up in a few days.

In an aggressive tune you are replacing gas with meth for fuel. The meth becomes part of the needed fuel to keep the car together. In a safe tune it is extra on top. The idea on the safe side is that if your meth fails the car should survive without it. Both work but you need to decide if the risks are worth it. I almost always go on the safe side.

 

I set the meth to start ramping in at 4 psi. We tune the VE (OLSD)around the meth to an A/F of 11.2-11.5-1.

 

a progressive meth kit is best. some good reading here..http://www.alkycontrol.com/

 

This is how I'm going to do it.

 

I don't have a progressive kit so I didn't start at 4 psi. I started at 8 psi with a single stage pump. If you have detonation issues below 8 psi you shouldn't be relying so hard on meth.

 

I am using a progressive kit.
I was not sure how many guys run meth dependent VS meth supplemented.

 

I was in your boat a year ago and I listened to slow hawk. I set me pe and be to 11.0 and left it alone. I have the meth come in around 6psi, I logged afr error and reduced in the ve to fine tune it to the 11.0 afr the car is commanding. I did this at the track, actually was really fun.

If you are running a dual kit you will need to pull out a lot of fuel, keep an eye on the wideband, if you know your correct target you will know if there is a failure. I also have an activation light and a seperate flow light.

 

I did buy dual nozzles just to make sure I don't run out of fuel. The plan is to set the tune up at max boost/fuel with no meth. Then add meth and adjust VE as stated by Slowhawk. Hope to have some new numbers after Tuesday.

Currently at 8# she is a little rich, running around 10.5-10.8. This is with no meth installed yet.

 

Thanks for posting the question, I too needed some answers. Devilish thanks for the link. Good read!

 

+1

I tune mine like this also.

 

Good info.

 

It is going to depend on how much meth you are throwing at the motor as to how much fuel you have to pull. Could be as much as a full point on the afr scale or more. Make sure you have failsafes because if for some reason that meth is not there, you will go lean and pop the motor if you don't see it soon enough. Some kits have the ability to flip a relay if they don't sense flow. Set that up to trigger something in the tune to go rich. Hope that makes sense. Just one reason meth kinda scares me, but I have tuned a lot of cars that use it successfully for years. Only had 2 failures of the meth that I knew of. One of the two lost a motor.

 

AEM Just came out with a new progressive meth kit that really cool. They also have the fail safe gauge that can be wired in to something like your air temp sensor to pull timing if your meth runs out or fails.
http://www.saccitycorvette.com/AEMMe...ctionkits.html

 

I would get something with a flowmeter. You can still have a full tank of meth and get a clogged nozzle like what happened to a buddy of mine. Crap happens, the flow meter will help as it will kick a signal any time it senses flow under a certain volume. The dummy lights are about useless. By the time you see a dummy light it is probably too late.

 

Mine is over 2 points in difference. Yes, very dependent on methanol. Not worried about it. 50 passes last year.

 

My buddy wasn't either til his motor popped. His kit had a dummy light warning system. Was too late by the time he lifted. The kits with the flowmeter options are NOT that much more and could potentially save a motor. Just saying.

 

I have an Aquamist kit, and highly recommend it. Failsafes can be programmed in, especially with a boost controller to where you can dump boost if it fails, or pull timing, or whatever you like.

 

im sure there are so many ways to tune for meth but if you're asking for the CORRECT way then you have to do it using Lambda, shoot for say 0.785 Lambda on 93 octane, max it out, then turn on the meth spray and adjust USING THE METH CONTROLLER until your Lambda goes back to 0.785ish. You will gain power due to cooler intake air temps, and your IAT vs spark table should also add some timing if its tuned correctly. If meth fails you're safe