Any new info or impressions of driving the car on e85 to report here? Small issues that have popped up? I'd love to see mpg on e85 vs gasoline too.

 

Logging the drive to work again, the BLM'S were more in line, looking to be around 130/127 while cruising 75 in 6th around 2100 RPM's. If you PM me your email I can send you the DataMaster and .bin files to look over if you like.

 

Ive been running E85 in my turbo car for the last 3-4 months and I really like it. Im running a speed density tune and keep a close eye on my a/f. Lambda is 1 whether its gas, e85, or someother mixture of the two.

I left my wideband set for gas afr since thats what I am familiar with seeing. Stoich is still 14.7 and I look for 12.0 WOT.

 

WS6T3rror, I made the tweak to the idle under/over timing tables, zeroing out to 50 rpm that you suggested, along with zeroing out the EGR tables since I no longer have EGR.

I left the injector constant the same and decided to run in Speed Density and see what the scan read. I was suprised to find that the LT BLM's hovered in the 140's now instead of around 126-131 with the MAF, and the left BLM's were still slightly higher on he left . Is this difference between SD and MAF normal, or is there something wrong? I wanted to run SD to get the VE tables close, then switch back to MAF and work on the MAF calibration and PE tables afterwards. I know a wideband is needed to get the most accurate tune, but I just want to get it as close as possible before I get the wideband.

 

No, no problem with the speed density trims being diff than maf. The maf and the ve calibration dont have much to do with each other and ve tables aren't very good with mods which you have. Be glad, you're just moving more air than the factory map is calibrated for. The difference is because the ve table is static and the maf mode actually measures airflow it doesnt care about anything else.

Imo, for a good tune you should tune speed density and maf mode both. Just log with freescan run it through ve master and then check again, when you get speed density mode running good flip back over to maf. Thats usually the process i go through when starting from scratch.

I also usually lean out the open loop tables, but with e85 richer may be better. Honestly though if it doesnt reak of booze and starts well I wouldn't mess with it.

Did you by chance add any timing to the idle in the closed throttle tps settings. You should add a couple of degrees there and it should help the idle further. It should now be very steady with the changes I suggested.

Only other thing is for you to give us mpg numbers and other thoughts about how it runs and drives. Oh and check out your exhaust, depending on how much e85 you've run through it, the pipe color should start lo lighten and become transparent if there isnt too much baked on soot.

 

Well I've got the SD BLM'S close, so switched back to MAF and while they are close to 128 on right, the left is showing consistently leaner across the board. I logged for about 30 minutes and then used excel to export the LT BLM's vs AFGS and the left side is consistently leaner across the board, average was I think 4.6% lean and the right was around .8% lean.

Is there an issue with the car or should I adjust something else in the tune?

 

Driving impressions so far are that it does run a little smoother than gas, mileage is averaging around 14.8 mpg my last 2 fillups vs about 18-19 mpg before for my usual commute.

 

No dont adjust anything my car does the same thing, except at higher airflows. My dr side blm is always about 2-4pts higher than the left I have no idea how to fix it and I have gone to great lengths, including putting a thermocouple on each pipe and adjusting individual cylinder fuel trims. To no real effect except my idle blms are dead on now, probably just me adjusting the thing to run richer where it needed to which the computer was doing anyway.

I have switched to e85 too now, it finally got cheaper than gasoline by a large enough margin for me to run it and it be economical. My mileage did not decrease as significantly as yours did but I have much higher compression. I was having trouble with false knock which I tuned out of my e85 tune. I think I will stick with it for the summertime unless i get tired of filling up all the fricken time . My fans have yet to come on since I made the switch which is really nice imo for summer because on gas they were always on in traffic.

 

What compression are you running? I'm around 11.1. What did you adjust in your tune for the E85? Just wondering basic things such as injector constant, timing, etc.

 

I just calculated down 33% less capacity for injectors. My compression is 11.37 it cranks 230psi on the gauge. I redid the ve maps a little and tweaked the open loop and just added 2 degrees everywhere to timing. Thats about as far as I had to go outside of the usual pe massaging.

 

Good info guys....


im trying to catch up a little, make sure i have this right.


on a stock pcm
H/C/I Lt1
30 svo injectors


Drop the injector constant down ~30-33%
( this will change the 14.7 to a 9.76 for the E85)

Run VE Master a few times on the e85 and shoot for what 128?? My friends gas LT H/C/I likes 126

Add 2* of timing across the board ( i read on some other board 4-5* at WOT)

Check WOT for a 7.7 A/F or a 0.71-0.86 Lambda




Does that sound right??


I have a friends car i can play with till i order my 83 lb injectors for my car.



Thanks for the help

 

Thats pretty much correct. Just be careful running out of fuel pump and injector on e85 since the load is going to be quite a bit higher.

If your ve map is very good to begin with on gas you can work it with the injector constant. Still have to up the pe enrichment since the lamda is going to be lower on the e85.

Doesnt matter what you shoot for with the blms wherever the computer settles the blm is going to be stoich. 128 is the ideal doesnt matter much if you're running the blm locker for pe. Helps the open loop and throttle response if you take the time to get it right and then smooth the maps out nicely.

All of the ve table stuff only applies to speed density which most do not run. If you have the maf enabled then its pretty much the same method but different tables to adjust.

Do be aware that e85 changes mixture throughout the year and you may want to keep a wideband in the car to verify that the wot mixture is where you want it. E85 does have a fairly wide tuning window compared to gas though.

Idk about using 5 degrees more timing under wot. I'd have to verify that on the dyno. I dont really think it times all that much different than gas.

 

Are you guys making any physical changes to your fueling systems as far as ethanol being more corrosive, or is that just bogus?

 

Not making any changes as far as materials. The system was designed for 10% ethanol mix anyways, its good for 100% ethanol as far as that goes. My car is set up with braided lines which are teflon lined but thats not because of the fuel I am using.

Methanol which is what people are refering too in racing as 'alcohol' is far more corrosive and needs major changes. Methanol is nasty nasty stuff and certainly not for street use.

 

As far as timing, once I got my car on the dyno, adding timing only got me about 2 rwhp/3rwtq with about 2* more timing and adding more gained no extra HP.

I was only stock cam, stock intake with some pretty mild ported heads, only putting down 322/338 and I was maxing out the 30# SVO injectors at 100% DC around 4400 RPM if I remember correctly. So if you are running H/C/I, you will definitely max out those injectors.

WOT I would look for around .8 lambda for power.