Ferocity02

iTrader: (59)

I am currently running an EFILive custom OS, semi-open loop speed density 2bar. I'm running on 91 octane, but I'm assuming I'm actually getting E10 from the pump. No meth injection at the moment to get the VE tables for vacuum and boost dialed in. The most boost I've seen is 9.5psi at which the AFR is 10.8-11.0 with ~14 deg timing. My IAT's stay fairly low, like 10-15F above ambient even in boost. I'd like to get up to 13-15psi, but will this timing and AFR still be safe with 91? Haven't seen any knock retard at all yet.

My plan is to inject a 33/67 or 50/50 mix of meth/water above 8psi or so at 15gph. I like to think of the meth/water injection as a safety net for the high boost levels. What in the tune needs to be done to maximize the benefits of meth/water? I'm assuming I can only increase AFR and timing. Any thoughts on how much they can be increased? I'd like to keep the tune pretty safe since it's my daily driver, but hoping for around 600rwhp. Other mods in sig.

Thanks!

black4.8

iTrader: (1)

get the a/f in the high 11's w/o meth. should put you around 11.0 w/ meth. if the meth fails you still will be in safe a/f ratio. could probably bump the timing to at least 16* or so. just watch for knock. btw 70/30 meth mix is best. i played w/ mixtures for a year and that worked best for cooling and hp. dual nozzles also will work better than one big one(10 and 5gph or two 7gph nozzles).

Ferocity02

iTrader: (59)

Thanks for the reply. I would do a higher meth/water ratio, but I also use it as windshield washer fluid and would feel bad about wasting the meth on my windshield

I have dual 7gph nozzles, which I tested to flow about 15.5gph combined at the 14V that my truck runs at.

black4.8

iTrader: (1)

your probably lose almost a full point a/f injecting 50/50 mix. *warning its addictive* i started at 10gph now i inject 26gph. my motor is very meth addicted.

Ferocity02

iTrader: (59)

So lets say my tune is dialed in on 91 octane up to 11.5psi, 11.3 AFR and 10-12 deg of timing. Can I just start spraying with this tune and then adjust accordingly, or should I adjust the tune first and then spray? I feel like I'm at the limit of 91 now so I'm hesitant to lean it out or add timing w/o spraying. The plan is to use 50/50 water/meth at 15.5gph total.

o2camaross

iTrader: (2)

^ this, I've always wondered this as well

Random User

I'm running it 50/50 by weight, not volume strictly as a safety measure. Any added power is just a bonus.
I talked with my tuner and he suggested no changes to the tune in my case.

Ferocity02

iTrader: (59)

I was thinking that spraying a 50/50 mix of water/meth without changing the tune would actually reduce power, is this incorrect?

My main concern was whether or not spraying water/meth without changing the tune could cause damage.

black4.8

iTrader: (1)

it will richen it up a little, you seem to be a little rich already so i would get it tuned. will lose some power if not. just up the boost a little. lol

Random User

My A/F hovers around 11.5-11.7 at WOT....it's kinda hard to watch the needle since it's always moving but I definitely feel no loss of power. I don't subscribe to butt dynos so I won't post what I thought I felt as far as increases go.