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      02-04-2012, 10:16 PM   #95
Brigadier General

Drives: 08 E90 M3, 99 E36 M3 Turbo
Join Date: Feb 2011
Location: Concord, NH

iTrader: (3)

Originally Posted by DylanMckay View Post

Shiv, how much more timing are you able to advance with the meth tune v. your regular non-meth tune? Also is the a/f changed for the meth tune? I am assuming you can run much leaner with meth as well?

I ask because looking at the dynos, it looks like you could be getting more from the meth with a tune. Considering your tune alone gives 15hp, meth alone with no tune gives you 10-15, you would (or I would) think a meth specific tune being able to almost be a similar tune you could do for 100 octane could yield a higher result than simply adding up the benefit of both above.

Is the methanol tune similar to a tune you would do on race gas?
"Methanol is sprayed into the air filter using two custom-made 1.0mm nozzles. At 100%DC, the system is rated at 750-800cc/min. This finely atomized spray drops intake temperatures considerably and raises knock resistance well beyond that of what you would get when running straight 100+ octane race fuel. With no other changes in mapping, this intake temp drop and octane bump is worth up to 10whp and near perfect run-to-run consistency. Coupled with a PROcede-induced ignition advance bump, another 5-10whp can be realized in a naturally aspirated application."

"Without meth, most of the power gains afforded by any tuning solution (flash or otherwise) comes from running a 2-3 deg ignition advance in the upper midrange. This fills out the dip in power at ~7000rpm. I have yet to see any evidence of power gains as a result of VANOS tuning. And then again above 7000rpm, a bit more power can be extracted by enleaning AFR slightly (by just ~0.5 point).

And with meth spraying, additional power is passively gained by dropping inlet charge temps (higher air density) and by running another 2-3 deg of timing throughout most of the power band.

So to answer your question, ignition timing is the best contributor to power gains. Not surprising considering the gains that people see by just adding race gas and letting the DME run it's maximum timing set points. But at $7-8/gallon, that gets expensive/inconvenient after a while."

The way I read this, Vishnu's meth spray alone without Vishnu's tune is like running 100 octane race gas and worth 10 rwhp, mostly due to a 2-3 degree timing advance. Add Vishnu's tune and you will gain another 5-10 rwhp by advancing timing 2-3 degrees through out most of the power band with maybe a bit more power above 7000 rpm by leaning out the mixture by half a point.

You are welcome.

More spoon feeding for the busy boy with no time to look for himself but time to write a snappy response:

Last edited by pbonsalb; 02-04-2012 at 10:27 PM.