I did notice my exhaust smell the other day. I had the t-tops off and was backing out of a parking spot. It smells like a guy that has been drinking all night, hasn't showered, and has sweated out all the booze. Atleast that is my opinion. As far as emissions, if you are on the E85, you shouldn't have a problem since it burns cleaner. Let us know what you find out.

 

i dont know if this has been covered. but how could you make it a "flex fuel" vehicle. in that the computer automaticly adjusts for any combination of 0%-85% alcohol... thats what i want

 

The only way I can think of is to let the fuel trims adjust for the difference. You would have to skew the injector flow rate to the rich side, for gas, lean for E-85. You could just subtract 15% from the whole IFR table, causing 15% more fuel to be injected. The 02 sensors only know when then AFR is Stoich, so when it runs leans on E-85 the 02's tell the fuel trims to add more fuel. And when the 02 sensors, sense a rich condition they would tell the fuel trims to trim fuel. All this assuming that your tuned well and have the fuel trims 0 or close to it, you should end up with fuel trims no more than +15% and no less then -15%. I have not tried this. I just use E-85 all the time because it is readily available to me. So, I am not sure how well it will work for WOT, but should work for part throttle. If you try it let us know how it works.

 

Never tried it, but I have seen kits that plug in between the injectors that are supposed to adjust for the percentage. Not sure exactly how it works

 

Just to throw a twist to the E-85 discussion. I was looking at some information regarding valve seats. The vehicles designed to run on E85 have different intake seats than normal unleaded fuel heads. Also they are adding the same seatmaterial to the exhaust side for 2009 and beyond.

 

Well, I have been running E85 on my TransAm for about three weeks now. I log all my fuel usage and maintenance on a small note pad. Here is what I have found out. With no fine tuning just changing the A/F ratio to 9.799, stock exhaust manifolds and cats, I lost about 15% on average in fuel economy. That is a mix between highway and city driving. But, with premium gas around Indy at $4.09 to $4.21 a gallon and the E85 as low as $2.79, the cost difference is 32% cheaper to use E85. So yes, I am not going as far on a tank of fuel, but I am saving more money going the same amount of miles. I also believe the lower drop in fuel economy come from the fact that the LS1 is a higher compression motor compared to the flex fuel cars, so we take advange of the high octane. Other than the cold starts and funky alcoholic smell, I rather like it.

 

Again... I wonder how it affects emissions. I'd totally run E85 if it'll allow me to run without cats and still pass smog.

-B

 

When I get my blown 402 switched to E85, I would like to get a smog check to see if it does pass.

 

Mine passed emissions just fine. Even with the extra fuel dumping in from the large injectors.

 

add higher compression pistons or mill the heads and take advantage of the higher octane rating

 

Hey Everyone,
I have been making GM Trucks run flex fuel for about 6 months now. It is working great. Around here, the price of 89 is $3.89, and the price of E-85 varies greatly from 2.69 - 3.20. Anywho, after I do the tune, I give the customers a simple equation to check if you are really saving money.

$/mile = Price of Fuel / MPG Achieved on average.
I have seen that E-85 after my tune up is running $0.03/mile better than gas.

 

Ive tried to search, cant find what I am looking for.

But, I have milled heads and running 11.5.1 CR and also run spray. 9 times out of 10 I fill up with 100 octane which is a little over 6 bucks a gallon now. So, I think an E85 conversion would be good for me.

I have EFILive but not real familiar with it. SO, I have the capablilites to change / tune on the go.

I have a Granatelli (SP) 255 pump (the walbro took a **** on me last weekend actually) along with 36lb injectors an a adjustable fuel pressure regulator if that makes any difference..

Question is, what tables do I need to change exactly???

I know spark, fuel and from what I am reading I need to change the AF to read something different. I do have a wideband in my car as well.

Thanks.

 

All you have to change is the Stoich value from 14.63 to 9.765. If you are already set up for max power changeing the timing wont have much if any effect. I'll check my other PC for the table #

 

B3601 you can pm me your e-mail if you like and I can send you a copy of my tune.

 

If your running a D1SC, I dont see how plugging in your tune into my car would do any good. Or is it a table that is does not matter?

 

Fuel ........................ AFRst ........ FARst ....... Equivalence Ratio ... Lambda
Gas stoich ................ 14.7 .......... 0.068 ................ 1 ................... 1
Gas max power rich .... 12.5 .......... 0.08 ................. 1.176 .............. 0.8503
Gas max power lean .... 13.23 ........ 0.0755 .............. 1.111 ............. 0.900
E85 stoich .................. 9.765 ....... 0.10235 ............ 1 ................... 1
E85 max power rich ...... 6.975 ....... 0.1434 .............. 1.40 ............... 0.7143
E85 max power lean ..... 8.4687 ...... 0.118 ............... 1.153 .............. 0.8673
E100 stoich ................ 9.0078 ...... 0.111 ............... 1 .................... 1
E100 max power rich .... 6.429 ........ 0.155 .............. 1.4 .................. 0.714
E100 max power lean .... 7.8 .... ...... 0.128 .............. 1.15 ................ 0.870



So, know I will be using these AF numbers correct?

 

I wouldn't recommend plugging in anyones tune but your own, it was just for you to look at and compare tables. I picked up quite a bit from the timing changes I made to the tune I got with blower.

 

That's the one I used. I rounded off to 9.8 and 8.5

 

Yea, no doubt.


Im just wondering if anyone has put together to say like.

EFIlive in this example

Table # BXXXX add 23% for more fuel
add 1 to injector flow rate
yadda yadda yadda. Catch my drift?

That will get a person close and atleast be able to put E85 in and get the car running and do some fine tuning.

I have no idea what table/chart to change and by how much.

 

E85 stoich .................. 9.765
E85 max power rich ...... 6.975
E85 max power lean ..... 8.4687

Well, if all rules still apply... Wouldnt you use 6.9 (rich) and 8.4 (lean) for WOT and not worry about the 9.7.