thx for the help! I think 1450cc injectors would be ok...or maybe 1600cc? Does anyone know the limit for what you can idle and run reliably on the stock ecu? I'm currently running an AEM EMS, but i might want to go back to stock ecu for emissions etc..

 

There are several people who are running 1450 cc/min injectors with E85 on the stock ECU no problem. Gasoline might be a bit tough to get a decent idle though.

 

^^^^ I run the FIC Bluemax 1450's on pump gas. It just took 2 weeks to scale them properly because I was learning in the process. Bryan would have got it done in an hour!

I just bought 5 gallons of E85 for testing!

 

awesome. I'm taking out the AEM EMS tomorrow and going back to stock ecu w/tune. I just ordered the 1450cc blues from FIC so I should be in business by next week.

 

Does anyone have a link to what the stock Evo9 fuel pump flows? I have one in my 95' TSI and am wondering if I can get away with running E85 on low boost on my 14b.

 

Courtesy of AMS, the Walbro 255, VIII, IX, and X pumps compared:

 

Thanks for the graph!

 

are you watching egt's as well tuning for 12.1 afr on e85?

 

Nope. My feeling is that E85 is most forgiving fuel out there. It absorbs more heat during evaporation, burns cooler than gasoline, and there is more E85 in the cylinder during ignition (30% more than if it were gasoline at 12:1). Besides, 12:1 isn't a big deal. There are people running 12:1 on gasoline in the upper RPM range, and many people tune 93 oct gasoline at 11.5:1 across the rev range.

 

I've seen lower EGT's on the E85 evos equipped with EGT gauges.

- Bryan

 

Bryan-

Curiosity will probably kill me like a cat but what the hell... What's the leanest you would ever tune on E85?

-E

 

I've run my car to 12.5 at WOT but I haven't found any power differences. I run it "normally" at around 11.8 to 12.1 depending on the usage and application.

On the dyno I have seen no significant power differences between high 11's and mid 12's.

I have however seen knock sum "noise" clean up when you move into the low 12's. By knock noise I mean random 1's and 2's.

The exhaust note changes at leaner mixtures but I'm a wuss and if I don't see large power gains to warrant the risk, I bring it back down. With my own car I get a little more curious but with customers, they don't pay me to blow their cars up.

 

Good to know... Thank you!! Just wanted an "alert" number to watch for. Not about to throw a just spent 6K dollar build down the drain getting overzealous.

-E

 

Bump for a good thread

 

I know of some E85 cars that have been run in the 12.8 to 13.2 A/F range and at times even leaner for over 6 months and making close if not 600AWHP on E85... stock engine no failures or problems AT ALL. Im certainly not telling everyone to run there cars at 13.5 etc lol so dont get me wrong here. BUT If you can run 93 gasoline to 12.0 on a good tune then why not E85 to 12.5-13.0 A/F... That is the question

Now on smaller less efficient turbos where there running higher boost and are less efficient "hotter air, more back pressure etc..." I would obviously run the A/Fs more conservative to help cool and use the that effect ethanol has to your advantage...