E85Forum.com

geddy2112 · Joined: 20 Jul 2010 Posts: 4

Well, after reading and linking up with Tim at Johnston Motorsports, i made the switch to E85 last week. I installed a bigger fuel filter and a new stainless filter element on my existing fuel system which consist of a Aeromotive Eliminator pump and Injector Dynamic 1000cc injectors. She fired up right away.

A little info on the car. SBF with a Precision 78mm turbo, A/A intercooler, TH400, solid roller cam, FAST 4 blade throttle body, 3.27 gears and a FAST XFI ECU.

I did have some issues in the beginning with some parameter settings on my FAST XFI software. I had changed the fuel energy constant to .68 from 1.00, and added 30% more fuel to my VE table. It was tough trying to remember the new AFR number for E85 because i was so used to looking at the AFR numbers in a gas tune. Initially, the car didn't want to warm up at all. It was barely running. The header tubes were not getting hot. My garage started to get fumey. After lowering the VE numbers in my idle area, it got better but i was struggling to get a good idle. So, i shut the car down after 10minutes. I regroup and ditched reading AFR. I changed the Fuel Energy constant back to 1.00 in the software, and also converted everything to Lambda. Restarted the car. And after 1 minute, i had her idling perfect at .87 lambda which is about 12.7 AFR. For some odd reason there was something about AFR that was just not flowing with me on E85. I slowly played around with the VE numbers in the idle area and she idles great now. The first thing i noticed is that car runs cooler for sure. between 20-25 degs. For the next few days, i played around with the cold start settings and now she starts at pretty much and tempertures. I had to take out more than 1/2 of the cold start fuel. I am still playing with this table because the weather has not been too cold here in New York yet. I drove the car out last weekend and i am surprised that by leaving Fuel Energy Constant at 1 and adding 30% more fue to the entire VE table, the tune was super close to the new close loop table i had created for E85. With the exception of idle area, i really have not touch the rest of the table. Logging and watch my O2 correction with my FAST ECU, it had to correct very very little.
The drive feel i got with E85 is it feels like you are driving a ice cold car that you just started. The gas pedel feel is very responsive and peppy. I have taken the car up to 8lbs of boost so far and still have not touch the VE table.
Really glad that i made the switch to E85. A hotrod that is enviromental friendly. Sorta. Thanks to Mark Sullens for a great E85 lambda, AFR table and Tim at Johnston Motorsport.

Drag Chevette · Joined: 18 Sep 2007 Posts: 458

geddy2112 · Joined: 20 Jul 2010 Posts: 4

440Jim · Joined: 01 Jan 2008 Posts: 188

Sounds like a great success story, and help from the web (Mark).

For plain old idle, I am sure you could lean it out to Lambda =1.0 or even leaner. But I don't know how that would effect your transition to applying the throttle, etc.

When I warm up my race car on E85, or even driving in the pits to keep heat in the motor, I lean the engine to Lambda ~1.02
Now my BB Mopar is normally aspirated, but for what it is worth, I go WOT around Lambda=0.87, and have tried as rich as 0.80 (best power in cold air).