69-chvl

iTrader: (11)

I run 93 octane with a whiff of 50/50 water/meth. Last couple of track outings I put 5 gals of 100 octane in there and the car almost wouldn't idle...had to jack the idle speed up and it seems to run rough. Didnt really run up top as good as I thought it should, and the datalogs showed less lbs/hr consumed. Guess I need to add alot more timing and adjust the afr even for this little bit of extra octane?

And another question, can you have one tune that covers both pump and race fuel, or do you have another tune for race fuel?

Just is just an stock LQ9, LS6 cam, 11* of timing up top.

01ssreda4

iTrader: (96)

What fuel are you running? Are you running 02 sensors? If you are you need unleaded fuel. I ran ms109 which is 105 octane unleaded and oxygenated and the car loved it. Ran really well. I needed to added about 5 percent to my VE table to get afrs dialed in and once back in closed loop the pcm was able to hit it's target.

69-chvl

iTrader: (11)

VP 100 octane, Unleaded I believe. Yes running Holley O2 with closed loop correction. It just didnt like it...maybe it was the wrong fuel to run??? Its what the guy recommended.

gsxrred1000

iTrader: (3)

Been down this road. If your trying to run same tune on race fuel that is usually pump and meth it will need min 3-4 degeees more timing and lean it out high 11’s afr. Idle also goes to **** and will need work. Basically need a pump gas tune and separate race fuel tune.

69-chvl

iTrader: (11)

Thanks...kinda what I was thinking. Shame there isnt a sensor that detects octane and then the tune could correct itself. Or is there such a thing???

Bad Apache

Nope. Plus different fuels can have different properties. So one company's 110 octane will require different timing and idle settings, etc. An old friend said to pick the fuel that is as close to the requirements of your combo as possible and stick with it. Fuels with too high of an octane rating caused him power loss and fuels with too little, well you know. I would think E10-E85 and an ethanol content sensor would be the way to go for most of us. Good luck on your tune!

ddnspider

iTrader: (26)

How much boost? 11 degrees seems light if youre spraying meth, and definitely light when you put the race gas in.

69-chvl

iTrader: (11)

It is light. Didn’t want to run more until I hit the dyno. Running up to 15-16 psi. Only a very little meth. I bet it probably wants another 5-6* of timing, but leaving it put until I can confirm it.

H.P.Ranch1

93 pump only 11* timing, 116 11* timing only. When adding 1* to 116 hp fell 40hp.

Detoxx03

iTrader: (14)

Before I switched to a flex fuel setup I would run a separate tune with Sunoco 104 unleaded. Just switched the tune with hp tuners and hit the road. Love the new setup much better but the old one worked fine with the exception of manually switching tunes and dealing with the cost of race gas.

H.P.Ranch1

The camaro in my previous post runs a HALTECH Elite 950 with a thumb wheel added to switch between tunes owner loves it.

forcd ind

iTrader: (7)

If you had E85 you could have one tune and control it with the V4 upgrade with the sliding scale.
The Holley is pretty sensitive to some changes, anymore I have a dup. tune if I make a change, bring in the CL early-just rerouting my PCV killed a set of plugs, so I learned from that, lol

69-chvl

iTrader: (11)

I know and like that idea but there is no e85 pumps around here unfortunately.

Not to mention upping the fuel system and the poorer mileage combined with a damn small 14 gallon Mustang tank. So the race fuel option makes sense for the few times the car sees the track.