Brandon Ranvek also ran it (might've been the first) and he's the buddy I referenced that is swaying my decision towards E85. He's also the one I referenced earlier in the thread that netted 282whp-- I'll be using the same tuner and same dyno, actually.

Edit: didn't look closely at the name. We're talking about the same car since Andrew bought Brandon's Evo. I am also now the proud owner of the AST 5200's that were previously on the car.

 

Thought about that but it only affects the tune so it's a relatively easy adjustment when the time comes.

 

Good point and the only boost control mod I have is a boost pill delete which I know is not STU legal, but probably won't be protested on a local level. If I go to Nationals (which I don't foresee for at least a couple years in my car), I'll definitely change that. If I decide to stick with a single, low-boost E85 tune it might be worthwhile to add the boost pill back in.

I feel like I'm just being a naysayer to every comment so I'm hope I'm not coming off as too dismissive.

 

Marshall's right. Without changing the pill your two tunes won't be different enough. I had my tuner do an STU tune and a "whatever" tune and the whatever tune only netted me like 3 lb/ft and 1 whp or something like that. It's not like the Subarus where the ECU alone can get you 50 wtq.

I wouldn't run with the pill deleted even locally... that's a pretty big performance potential IMHO, just run ASP and compare with STU times.

IMHO, 100 octane for big events, 93 octane for everything else, and then you don't have to worry about what blend of gas your local station has. I think the car is plenty hilarious with 93 octane and a good STU tune.

 

what's 40hp between friends?

the boost pill delete is pretty significant IMO. equivalent to running 245 hoosiers, i mean they're the same width right?

 

the other thing to keep in mind is you're going to be intentionally running the car out of fuel. lots of risk in doing that for something that is going to be 'outlawed' anyway.

if you're going to do e85 might as well go all the way to 400hp and have a blast in ASP.

 

Yes the boost pill will be gone but I'll still run the stock boost map at events. Unless you're saying the boost pill delete will affect the stock boost map, then yes, I'd agree it's significant.

 

Thanks for the insight on the "whatever" tune-- that pretty much eliminates two tunes on E85.

Do you use an additive to get to 100 octane or get it from a station? Mind saying what numbers you put down on your 100 octane tune? E85 is available all over here in Minnesota so I have three stations within 9 miles of my house, but 100 octane is only available at a raceway 40 miles away, so, if only for that reason, E85 is slightly more appealing.

I think I still have the stock boost pill so I'll consider throwing that back on, especially if it really affects the stock boost map.

 

STU is very strict about no modifications to the boost control system. The boost pill delete is a huge mod to the boost control system. Removing it will change your boost levels, so it's definitely significant.

 

Brik if your considering octane boosters, i recommend reading the article below. Tests out all the major octane boosters out there. As you can see from the results many of them are useless... But Torco "race concentrate" and Lucas Octane Booster actually DO increase the octane rating significantly. I have used both with success. Slight miscalculations while mixing fuel and octane booster, can be safely tolerated with a conservative tune, leaving room for error. Similar to weather fluctuations and to protect in over-boost situations.

Both the top Octane boosters use MMT (form of magnesium) to increase octane. This is nothing new, Canada still uses MMT in their gasoline to bump octane points. FYI MMT will leave a reddish residue over the spark plugs.. Its harmless to the motor. But if the ratio is high, it will foul spark plugs.

Link below:

Octane Booster test

Another way is the homebrew way.. Which is to use Toluene or Xylene. Both can be used safely to bump the octane # or AKI.. Toluene is a natural ingredient of gasoline. Both have roughly an octane rating of 114ish. Both are used as a paint thinner, and can be purchased in bulk from a paint store (ie like Sherman Williams). There are various calculators over the net to calculate RON and such..

 

I ran e85 for a few events in STU with the stock fuel system and boost maps. IDC's were like 108% which I didn't like at all. It was good for about 20-30 hp and 30-40 torque over 91 octane, putting me about 290 whp and 310 torque (via VD) if I recall correctly. I am now back on gas just because the risk from that high of an IDC and the inconvenience of e85 wasn't worth it. Plus I couldn't get the warm starts right and that bothered the heck out of me. It can be done though.

 

^^^ Thanks for the additional insight.

I'm getting tuned today and I landed on 93 for the same reasons you mentioned, and also since I'm not anticipating being competitive enough to justify the relative risk and other (potential) downsides.

Also, I've added the boost pill added back in for legality's sake.

 

Thanks for the first hand experience input ! So it can definitely be done.. I may give it a shot, on low boost and see where my IDC% fall.

If you don't mind me asking, what values did you use to scale the stock injectors (~560cc, IIRC)?

 

Do you have a dyno chart posted anywhere? That is very interesting.

 

I know for me, my skill level isn't to the point where the additional power from e85 would make me any faster, it would probably just make me mess up more. The Evo on stock boost ad gas is plenty enough for me around an Autox course

I'd have to look back at the ROM's, I don't know off the top of my head. Yes, Evo injectors are 560's.

I have all my datalogs saved and may even have a screenshot from VD saved. I'll see what I can find when I get back to my computer.