E85Forum.com

Boosted3Bar · Joined: 14 Jul 2006 Posts: 50 Location: San Antonio, TX

My 60# injectors got here today and after I installed them, a full tank of E85 was put in her. A little tuning to get it to idle and cruise properly only took about 20 minutes. After that it was on to the fun part, WOT tuning!

I've been able to increase timing advance everywhere in the spark curve. I was amazed when the pcm was commanding 11* more advance at WOT than when running 93 octane. Torque is everywhere now, it is unbelievable! This car absolutely screams now, it pulls so much harder. I'm very confident that I'll be able to break out of the 14's and into the 13's with my grocery getter. My poor tranny is hating life now! I'm very happy I did the switch.

One thing I did not expect to really notice was the increase in exhaust volume. It is absolutely pouring out of my exhaust tips now, where as on gasoline you could barely feel anything coming out. It smells so good and the exhaust note is wonderfully deeper. I love ALKY! Very Happy

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2003 Grand Prix GTP

http://www.cardomain.com/ride/2155875

Revision · Joined: 14 Sep 2005 Posts: 194 Location: Carol Stream, IL

Well congratulations. Very Happy

E85 produces more exhaust gasses so it would probably help if you got a slightly larger exhaust system.

How is the volume/sound? Is it louder than before or quieter?

IMHO all the domestic car makers are missing out on something wonderful by not offering any of the sports cars as Flex Fuel vehicles. Sad

imprezarsc · Joined: 29 Jun 2005 Posts: 87

Congrats on the conversion. Any plans to up the boost a bit? Also, what are your IDC's like with the 60 pounders? I think you're one of the first tweaked domestics to come in and share your results. Keep it up Smile

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http://www.grantouringlabs.com My ethanol conversion and tuning site.

Boosted3Bar · Joined: 14 Jul 2006 Posts: 50 Location: San Antonio, TX

The exhaust is a little louder and much much deeper. The difference in the amount of exhaust gases is crazy, I'm glad I upgraded everything but the catback before I did this.

What are IDC's? Is that like IPW's (pulsewidth)? At idle they are about 2.4, which is very low, but it still idles fine on E85. With gas it was idling a little rough so I upped the idle rpm to 1300 on the way to fill up with E85.

Right now I'm just tuning to find the max timing I can run with my 3.4" supercharger pulley. Maybe in a couple days I'll throw the 3.2" pulley on there and pull some timing, and see which setup is quicker.

I can't believe GM does not offer any of their sports cars in a flex fuel model either. They are really missing out on a huge market of car enthusiasts.

I want to thank all of you guys on this board and the NASIOC board, this conversion went very smoothly because of all the stuff I've learned from you subie guys. I thought there was a firebird or camaro on this board that was running E85, but I haven't seen anything on his car lately.

I'll post an update when I switch pulleys and give a comparison. I'll also post some logs of 93 octane runs and E85 runs once my server is back online and working. (it doesn't look like you can attach excel files on this board)
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2003 Grand Prix GTP

http://www.cardomain.com/ride/2155875

Corn Squeezins · Joined: 14 Dec 2005 Posts: 42 Location: Madison, WI

So, your E85 hot rod 3.8 has now come to life, eh? What are you using for timing and fuel controls for this vehicle when u say u have added timing and idle, etc. Do you have some sort of power tuner module or laptop tuner module that u use? Do u use a scanner/data collection program as well as a separate program to modify your vehicle's PCM? I would like to know what kind as u seem to have good results/tunability with whatever u are using now. I have some friends that have late model Regals that may be very interested in your mods as far as computer controls. Any other mech. mods other than pulleys, injectors and exhaust (that u mentioned) done to this vehicle?

I have experienced the different smell of the exhaust, but volume/flow
of exhaust being different is a new one on me. I wonder why it would be significantly different in volume? It must be from the different combustion characteristics of the fuel as obviously not much else has changed, esp.
at idle that would make more air come out. Anyone else know what I might be missing as to this change?

Thanks in advance for your reply!

Corn Squeezins

Boosted3Bar · Joined: 14 Jul 2006 Posts: 50 Location: San Antonio, TX

I use the DHP (Digital Horse Power Inc.) Powrtuner. It is an interface box that allows my laptop to communicate with the pcm. The software it comes with is what we refer to as a tuner/scanner. It allows me to change nearly anything in the pcm (fueling, spark, fans, transmission, etc.) and record data from the sensors while driving. It also displays the sensor data as I'm driving on my computer screen, so it's like having almost any gauge I want. If they have ever been on clubgp.com they will know what the powrtuner is.

My mods are: TR55IX spark plugs (one heat range colder than stock, iridium), 180* drilled thermostat, fenderwell intake, throttle body spacer, ported exhaust manifolds, 3" downpipe, no cat, 60# injectors. I think that's it, for the engine anyway. It's a very small list for a GTP, I should barely be able to run the 3.4" pulley knock free, but with E85 I'm up to 25* timing advance with only a couple blips coming from my knock sensors. Stock timing is around 15* on the factory 3.8" pulley. I was running 12-14* (depending on outside temperature) on the 3.4" pulley with 93 octane, so to say my situation has improved is a crazy understatement. Even if you use a modest 2hp per degree of timing, I've gained over 20 hp just switching to E85.

As for the increased exhaust volume (cfm, not noise level) I believe it is just a property of burning alcohol. I can only imagine how this would improve spool up times for you turbo guys. With 93 octane I had to hold my hand right at my exhaust tip to feel any of the warm gas coming out, now I have plumes of warm exhaust coming out. I wonder if there will be a difference in the winter when you can see the exhaust coming out.

I can't say it enough how incredibly happy I am with a "mod" that saves me money everytime I fill up. The only bad thing is I'm only going to get a little over 300 miles on this first tank when I used to get about 400 with gasoline. I attribute this largely to my lack of control of my right foot, plus I'm tuning WOT which is just dumping the E85 out the tail pipes.

Sorry for the really long post but I get very worked up when I get 20 horse power (so far) from a "free" mod. I tried to give as much background info about my car as I could, but if you have any more questions on my setup, tune, etc. or have any info that may help me based on your tuning and experiences please share! I believe we are only at the beginning of the potential we can get from E85.
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2003 Grand Prix GTP

http://www.cardomain.com/ride/2155875

Boosted3Bar · Joined: 14 Jul 2006 Posts: 50 Location: San Antonio, TX

As promised here are a couple of scans (logs) of a couple of WOT runs. Again, any questions just ask, a lot of this is probably different than the subaru stuff most of ya'll are used to.

The first is all the mods I listed in the previous post with the 3.4" pulley:
http://www.scandepot.net/viewscan.php?pk=2693

The second is with E85 and 3.4" pulley, this is not my most recent, but very impressive none the less.
http://www.scandepot.net/viewscan.php?pk=2694

Notice how rich I had to run the 93 to keep the knock down, even with that much fuel I still had 5+* KR (knock retard, not good!).

With the E85 nearly no knock and a much more steady timing curve.

I'll post more scans as time permits, but the Woodward Dream Cruise is this weekend so much of my time will be spent staring at beautiful muscle cars.

I don't want to make any of you turbo guys jealous but if you look closely at the E85 scan you can see that I'm already into boost at 1800 rpm and 62% throttle. Spool up time of less than 200 RPM's. MAP = >101 = boost Wink

Just kidding, I have a bad case of turbo envy.
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2003 Grand Prix GTP

http://www.cardomain.com/ride/2155875

Revision · Joined: 14 Sep 2005 Posts: 194 Location: Carol Stream, IL

Very nice.
It worries me that timing changes so drastically on E85 when there have been papers published which suggest that E85 and neat gasoline should have the same timing values. Well only dyno results will tell. (hint hint nudge nudge Wink

)

Timing does increase though. Even on E30, I've seen an increase of 10 degrees of timing across the board and another 9 degrees or so of variable timing increase in some spots. The extra exhaust volume(cfm) does help turbo spool and I can't wait to get my project going to the next stage. Very Happy

Hey Hotrod, (whenever you read this) when are we going to get this

F.uel
E.thanol
L.ab
R.at
S.ociety

thing going? Laughing

Robotbeat · Joined: 18 Jul 2006 Posts: 31

How the heck does advancing the timing affect performance? Seriously, people keep talking about it, but I have no idea why it would help or how much it helps or anything. I can't find anything on wikipedia about it...

Revision · Joined: 14 Sep 2005 Posts: 194 Location: Carol Stream, IL

http://auto.howstuffworks.com/engine.htm

The best explaination of all. Smile

Robotbeat · Joined: 18 Jul 2006 Posts: 31

Thank you very much!

jachristner · Joined: 12 Oct 2005 Posts: 64 Location: Kokomo, IN

I didn't see much on timing in that How Stuff Works article. But I did find some good information on a couple other sites.

Basically, it all boiled down to the timing being dependent on the RPM. It stated that the ignition event and the fuel burn rate are always constant. Thus when the engine is at higher RPMs and the piston is moving faster, the ignition timing needs to be moved forward so the expansion is pushing the cylinder and not simply chasing it down the cylinder. This is why distributor ignitions used a base timing plus a mechanical or vacuum advancing mechanism. Computer controlled engines adjust the timing throughout the RPM range. Since ethanol has a higher octane and thus burns more slowly, advanced timing allows more of the expansion force to be put to work.

Will the newer computer controlled engines automatically advance the timing when running on ethanol? Is this the function of a knock sensor? How many late-model vehicles use a knock sensor?

hotrod · Joined: 19 Apr 2005 Posts: 872 Location: Colorado

Robotbeat · Joined: 18 Jul 2006 Posts: 31

Does the Motronic ECU in my V6 non-turbo 1995 900SE Saab change the timing in response to the octane or oxygen content or knocking sensor? I mean, is it automatically tweaking the engine for me? Or is this something you have to manually tune? (It's a distributor-less ignition system, BTW.)

jachristner · Joined: 12 Oct 2005 Posts: 64 Location: Kokomo, IN

I imagine on newer computer controlled vehicles, it's very difficult to manually adjust the timing. I don't know how many are designed to adjust using sensor data. For those that aren't, I'd guess it's some kind of built-in table much like the fueling data. This is just speculation on my part and hopefully someone with more knowledge will have something to say on it.

I'm planning on getting a CarChip E/X (http://www.davisnet.com/drive/products/drive_product.asp?pnum=08221) to use in tuning my Wrangler for E85 when I finally buy it. It will record 4 user-selectable parameters in addition to other standard data. Timing Advance is one of the choices along with Short-Term and Long-Term Fuel Trims.

To find out if your vehicle has a knock sensor, you could try looking for a replacement sensor. I did this with the Wrangler. After not being able to locate one, I've determined the 4L I6 was probably not designed with one.