I should be getting my car back Tuesday from CMS! They are installing a A&A supercharger. My car is stock other then some minor bolt ons. I don't race or run my car hard but is this a must have to be safe?(meth)

 

It's certainly not a "must-have". It's a little insurance policy. Tell your tuner you want a conservative (safe) tune and don't bitch about your #'s because they will be lower than a more aggressive tune with meth. Just take what you get and enjoy it because it will still be plenty.

 

Meth is a very good mod to do, and does not need to be strickly for power, is adds a good degree of safety.

 

I've been considering meth as well - when I change to the forged engine - I am not currently using it - but have leaned away from including it becasue of posts i saw where meth failure caused problems?

I'm worried about some meth failure causing problems?

If the tune is for including meth (even safe ) then if the meth system fails will it cause problems possibly?

Would a "safe" tune on pump gas be more reliable - less prone to issues - without the meth .. or?

 

You can run it lots of ways. you don' have to tune it to be meth dependent. You could:

- Tune it without the meth then spray on top for safety and lowered IAT's.
- Do the above but add timing in the lower IAT spark tables. If meth fails the timing goes back to pump gas timing levels
- Do the above but lean out the fueling back to ~11.5:1 when spraying. Now you end up with a truly meth dependent tune. I am planning on moving to option 3 here pretty soon.

 

chemical intercooler

 

If the motor is tuned super conservative then it shouldnt be needed. meaning boost kept mild-moderate, timing kept low, and air fuel on the rich side.

Once you start trying to get more power.. increase timing, lean it out, crank up the boost... you increase its octane requirement.. then its when its starts becoming needed.

Since you dont race or run your car hard.. then its a non issue.

Once you want more.. then you have to make those decisions.

Hope this helps.

 

Option 2 would require an IAT/MAF breakout, or an equivalent method of spraying meth upstream of IAT sensor, no? I'm option 3 and I'd like to be option 2.

 

I'm option two right now. Depends on the setup; since I am SD I just spray through the MAF since I'm only using it for the IAT but in most cases yes, break out the IAT and put it on the far side of the meth. Then either add timing in the IAT base table in the colder IAT boost region or add it to the main table and subtract timing from the higher IATs in the event of a meth failure. You just have to be mindful of the IAT's you're adding or subtracting with. Right now I add timing starting at ~65' but with this ~cold snap we're seeing, in the mornings I may see that even without the meth. But in the afternoons it's ~80 ambient so I'm good.

I have not been able to figure out a good way to lean it out on the meth and have it fatten up in case of a failure yet though. Especially on a 3rd gen PCM. The 4th gens have an IFR VS IAT table that I'm going to play with and see if it has an effect but the IFR VS Volts table doesn't (on an E40 at least) so I'm not hopeful so I'll end up with a truly meth dependent tune.

 

I think the key could be to use the IAT tables and vary what the computer see's based on system pressure.

Example lets say the resistance value of the IAT sensor is 100 ohms at 65 degree's(I dont know what the resistance value is since I have not graphed an IAT thermistor) and 200 ohms at at 130 degree's. When the alky system activates and starts to spray.. once it hits a pre-determined amount of pressure.. make the IAT read 100 ohms and give full timing and fueling correction. This can simply be done using a relay and resistor triggered by the meth system.

The only issue with doing things this way is that if your system lets say runs at 120 PSI pressure.. do you wait till it hits 120 PSI=delay or do it at lets say 60 PSI so things can get moving quicker in the motor. Most progressive systems start at lower pressure and ramp up. I guess some trial and error to setup a balance between drivability and safety.

Some applications run 20+ PSI boost and high timing.. those applications are hard to tame if a system where not to work.

Best advice is consult the MFG of your injection system, explain your situation.. and see if there are ways around your particular issue. Everyones combo is different, and there is no "blanket" way to cover everyone.

As always.. test your kits periodically.. pay attention to what the motor is doing.. and use some common sense. Example.. dont race the motor at high boost when the gas gauge reads "E", meth tanks reads low/empty, etc..

 

The guru has spoken.

 

Julio, is the test button on the AlkyControl kit adequate or should we be listening for the pump while testing or even disconnecting the line to ensure it spits out meth?

 

The test button provides a low voltage applied to spin the pump... pump spins moves liquid.. if the engine is running and you press the test button.. the motor will change the way it runs.. goes richer. If the motor changes the way it idles when you press test.. the system is working.

On cars I work on/tune/ etc.. I use the wideband for indication.. like at idle wideband reads 14:1.. hit the test and drop to 10:1. Same while cruising.. hit the button.. afr drops.. your lock and loaded.

Single nozzle kits with gain on 8 should change the LED color from red to green. Twin nozzle kits will need to get into boost to make the led change color.

Coming this Friday is a brand new programmable 150 PSI "Methanol PSI" gauge.. when you press the test button you'll see actual pressure. Records max pressure during a run.. allows you to change background colors when it hits your preset pressure.. Shh.. dont tell anyone ECS will have info on these this weekend.

 

Ohhhh, so excite!

I didn't have any idea this was coming so my other plan was to get an Aeroforce Interceptor and set up alerts for WOT IAT and AFR. Then I won't be so worried about setting up my tune for power and safety. I can just set it up for max power on the meth and then with the Aeroforce I'll be alerted if WOT IAT or WOT AFR passes a threshold.

 

Pitter, patter-don't forget to send some to your crack heads in Canada.

 

You know I never forget you guys up there

 

I have to ask... will this soon-to-be gauge have electronic isolation to keep meth out of the cabin?

 

I'm running meth on a stock block LS1 with 129k miles. Added it about 4k miles ago strictly for piece of mind since the flip-drive increased my boost to 9psi. So far so good(though I think I'm due for new lifters...)

 

Will include a special fitting(1/8 npt port) for the filter and have a stainless steel transducer mounted at the filter of the system. Then all you run is three(+,gnd,signal) 24 gauge wires from the transducer to the small module inside the cabin. Gauge hooks up to the module. The only additional wire will be a +12 contant so it can retain memory

The transducer wiring is very similar to the electric fuel pressure gauge from Autometer.

http://www.turbobuick.com/forums/alc...010-gauge.html
Is a teaser thread that started this back in July. Lots of testing to make sure its right.

Alcohol inside the cab is a big