Ethanol Blending

MKV727 said:

Spoke to an APR tech and he said the higher fueling trim won't cause fuel cuts with the stage 2 file but he seemed over his head when I mentioned the Ethanol mix.

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Yeah no one has ethanol maps for us. We are the innovators in this case! :smile: IMO Tuners won't want to deal with the uncontrolled variables on this (i.e so many fuel grades out there and the mixing of two fuels). E85 tunes maybe eventually for certain models...

The fuels trims can take a bit to stabilize but from my experience you just don't want fuel trims to go above 20% or your your car plays it safe and the CFs just stay pulled back at -12 (slow....) :thumbdown: Clearing codes fixes this until re-adaption goes past 20% again. You have the stock airbox like me so prolly will be nice and low. :thumbup:

I'll be jealous if you pull more than 180 g/s though...

junker said:

I thought this was a really nice article that explains why more power can be developed by advancing timing. Essentially, you are able to develop higher cylinder pressures which increases torque, and you get a head start on the burning process so that from TDC to say 30˚ the burn is kicking like a mule. Basically it's best to tune for the knock threshold and back off a few degrees.

http://autospeed.com/cms/title_Getting-the-Ignition-Timing-Right/A_109132/article.html

Back in the day I had 2 used MkI GTIs and all it took was rotating the distributor cap 5˚ for 10hp. :lol:

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I think something to add to that is the MBT area that should be kept in mind when pushing timing really aggressively.

MBT = Mean Best Timing or also known as Mean Best Spark.

MBT is the range of which the piston is in the perfect spot for combustion that will give the maximum amount of torque to the crankshaft. Spark in the MBT range results in the most powerful and efficient combustion. At a certain point, there is diminishing returns in regards to advanced timing.

MBT can be met by boost/timing/AFR and is generally a moving target based off of ambient conditions and engine speeds.

Say at 5200 RPMs 16psi, 24 degrees advance and 11.2 AFR is the MBT that is optimal at 72 F. The EMS will do its best to achieve it.

At 4200 RPMs, 19 psi, 20 degrees of timing and 11.0 AFR is the MBT that is best at 89 degrees. The EMS will remember the data and shoot for it in similar situations.

Our Bosch EMS has the ability to feel out the situation, it's not as easy as higher advance = more power like the older port injection motors.

It's a combination of XTiming + YBoost + ZAir/Fuel under ambient conditions. When looking for the best EtOH mix please keep in mind if you received more timing on one set up but less on another it doesn't mean the first set up is greater... You have to look at the whole group of data.

junker said:

:lol: Yeah no one has ethanol maps for us. We are the innovators in this case! :smile: IMO Tuners won't want to deal with the uncontrolled variables on this (i.e so many fuel grades out there and the mixing of two fuels). E85 tunes maybe eventually for certain models...

The fuels trims can take a bit to stabilize but from my experience you just don't want fuel trims to go above 20% or your your car plays it safe and the CFs just stay pulled back at -12 (slow....) :thumbdown: Clearing codes fixes this until re-adaption goes past 20% again. You have the stock airbox like me so prolly will be nice and low. :thumbup:

I'll be jealous if you pull more than 180 g/s though...

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Stock airbox + VWR filter + fin removal + Carbonio. I'm hoping for 180g/s but my biggest concern is the extra load on the fueling system due to needing more Ethanol for the same detonation as fuel.

I'm pretty sure my setup is already close to 180g/s as is right now though, I'll check it tonight when I get home.

Being pioneers is a pretty cool feeling... Perhaps there could be a way to capitalize on it that I'll PM you about later.

AFR

AFR Logs

Looks like the off-the-shelf Race File is written with a Lambda of 0.87 and the E20 blend is running at a Lamba of 0.86 - perfectly in the AFR zone for maximal power with no knocking. :wub: If I understand it correctly the oxygen sensor sees more O2 than it expected with gas and richens the mixture. Looks like some tuners get a little more power and lower EGTs running a little bit richer. That would be fun to try on a dyno.

Here is an updated EtOH calculator.

Better formatting and now uses a 3 part weighted-average to approximate octane rating (sans any cooling effects) using: 1) 113 octane for pure ethanol; 2) the octane rating of the gasoline (91/93), and 87 octane for the 15% in the E85.

Kind of gave me a headache but octane rating should be more accurate and conservative.

The estimated octane rating for the E20 blend from 91 Octane E6 is: 95.5 :w00t:

The estimated octane rating for the E20 blend from 3.5 gal E85 + 93 Octane E0 is: 96.8 :headbang:

The spreadsheet is posted on Google Docs so people can use it if interested at:

https://docs.google.com/spreadsheet/ccc?key=0AneBMyVsfsPMdGpNUm4taFBLZ1ZoczkxSXB4TGZQUFE

Just punch in:

• Volume of E85
• % ethanol in pump gas (0 or 5.9%)
• octane of pump gas (91/93)

junker said:

Here is an updated EtOH calculator.

Better formatting and now uses a 3 part weighted-average to approximate octane rating (sans any cooling effects) using: 1) 113 octane for pure ethanol; 2) the octane rating of the gasoline (91/93), and 87 octane for the 15% in the E85.

Kind of gave me a headache but octane rating should be more accurate and conservative.

The estimated octane rating for the E20 blend from 91 Octane E6 is: 95.5 :w00t:

The estimated octane rating for the E20 blend from 3.5 Gal 93 Octane E0 is: 96.8 :headbang:

The spreadsheet is posted on Google Docs so people can use it if interested at:

https://docs.google.com/spreadsheet/ccc?key=0AneBMyVsfsPMdGpNUm4taFBLZ1ZoczkxSXB4TGZQUFE

Just punch in:

• Volume of E85
• % ethanol in pump gas (0 or 5.9%)
• octane of pump gas (91/93)

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I redid the math and I'm afraid I might cheat...

I'm considering 6 gallons 100 octane, 3 gallons E85 and 5.5 gallons of 93 octane. I'm dying to get a rerun against a couple cars (cammed short bed, single cab 2wd 1500 Silverado that hung with me til 90 and a C5 that only gets me by 2 cars) in the 100 octane map and I think with that mix it may be possible to run the 100 octane file.

Depending on fuel trims I'll add either 50/50 E85 and 93 octane or 25/75 E85 and 93 octane respectively. I'll eventually find the minimum octane requirement and the max amount of EtOH to get the best results.

To go from regular pump to straight E85 it takes approximately 30% more fueling capabilities. I'll never exceed E25 no matter the circumstance as that amount of EtOH with EtOH free 93 octane will meet my octane requirement. I honestly think if I go stage 2+ with APR HPFP that'll give me enough room to not run into issues. I'll add a RS4 FRV for good measure to insure constant 129.99 bar pressure as specified by the tune.

I'm seeing a wide open market with the FSI/TSI platform and E85 fuel... If I can get an acceptable mix I may consider selling flex fuel conversion packages if the engine requires it at any point. Whether it be modified injectors, specific FRV's or other upgraded components. At one time WMI was something not considered viable for this platform either.

A solution to allow a higher capacity for the injectors without causing partial throttle nightmares or an entire recalibration is all that is needed. A medium in between the S3 injectors and the BPY injectors would be perfect. The EMS allows a 10-15% fuel trim adjustment so an injector that flows 10-20% greater in a fuel system that has E50 mix with a 20% greater fuel requirement would be within the amount of error (theoretically). It could keep the same pulse and maintain all of the functions of the EMS and be a basic drop in solution. It'd need a flow bench and thousands of miles of testing though.

Note: E85 isn't corrosive to cause any real damage to our engines therefore it'd be a waste to bother trying to "beef" up the components with better seals or anything of that nature.

MKV727 said:

I'm seeing a wide open market with the FSI/TSI platform and E85 fuel... If I can get an acceptable mix I may consider selling flex fuel conversion packages if the engine requires it at any point. Whether it be modified injectors, specific FRV's or other upgraded components. At one time WMI was something not considered viable for this platform either.

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If you can find a market opportunity go for it!

But for running straight E85 that would be interesting with the right fueling and tune. For long term E85 you would want to make sure there is no aluminum in the fuel system.

This is Thomas's build thread for his B5 S4 build that might be helpful even though it isn't DI.

http://www.audizine.com/forum/showthread.php/492815-Experiment-Logs-E85-91-Octane-Blend

Also, someone started a conversion thread back in the day using secondary injectors to run E85. I didn't follow it but would think S3, R, or RS4 injectors and a HPFP would be sufficient. I lot of conversions also do require an upgraded LPFP and the word on the street is the Golf R LPFP is upgraded.

check maf make sure its clean but it could take a little before ecu realizes it can suck in more air. not sure on that to be honest i dont remember paying too much attention to that value when i was logging, i just remember the time it took to cover the same distance dropped so i knew my changes had the impact i was looking for. i have been blending e85 for years even when i had my b5 s4 with ko4's.
even my initial log i had some e85 left in the tank but was logging intake temp not g/s but you can still see the engine speed increases and massive intake temp drops. couple that with the timing logs look better because the w/m brings my octane up to approx 109 henc e the reason i stopped using e85 and i now run racefile daily.
www.golfmkv.com/forums/showthread.php?t=131217

Cleaned MAF

vegasGTI said:

check maf make sure its clean but it could take a little before ecu realizes it can suck in more air. not sure on that to be honest i dont remember paying too much attention to that value when i was logging, i just remember the time it took to cover the same distance dropped so i knew my changes had the impact i was looking for. i have been blending e85 for years even when i had my b5 s4 with ko4's.
even my initial log i had some e85 left in the tank but was logging intake temp not g/s but you can still see the engine speed increases and massive intake temp drops. couple that with the timing logs look better because the w/m brings my octane up to approx 109 henc e the reason i stopped using e85 and i now run racefile daily.
www.golfmkv.com/forums/showthread.php?t=131217

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Cleaned MAF yesterday and re-logged in warmer temps (25 vs. 22.5˚C). Air mass still went up from ~179 to 183 g/s. :thumbup:

Next mod is to block off bottom section of the air snorkel feeding the engine bay to see if I can grab colder air and if there is any "ram air" effect. I'd like my current tune to be closer to 190 g/s.

Removed the curved section of the first main wing in the air box and partially covered drain hole to achieve 185 g/s on a warm, humid day. Feeling a little better about this flow rate now.

Fuel trim under 8%

Next project I am considering is an APR HPFP, RS4 FPV, and GIAC HPFP maps.

Has anyone been able to swap out the FPV without removing the manifold using crowfoot 14/17mm wrenches? Possible? Anyone in SoCal?

Ordered this 5 gallon fuel container so that I only need to visit PropelFuels every 3rd tank. Will be testing E20 made from 2.5 gallons of E85 to 12 gallons of 91 with an octane rating of about 95.

junker said:

Ordered this 5 gallon fuel container so that I only need to visit PropelFuels every 3rd tank. Will be testing E20 made from 2.5 gallons of E85 to 12 gallons of 91 with an octane rating of about 95.

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I'm waiting to run out of gas to try this myself, I didn't forget about it. Are you going to try GIAC's race file with the approximate 95 octane or just going to run the regular pump file?

Mixing up 2.5 gallons is only going to be 0.25 gallons less than what I am currently running with virtually no timing pull. For the most part the only time I occasionally see any pull is off idle and is usually only a single cylinder briefly at less 3˚.

It's possible that this E19.5 mix will run even better with the OTC file because it will be slightly less lean and may prevent the occasional low-load timing pull and possibly help reduce EGTs. As long as CF under load stay under 5˚ with a 2.5 to 12 blend I will be comfortable with it. Less fueling load as well. Someone without an IC upgrade may need to stay at 2.75. Not sure. Also, I installed my vented grill covers to help keep the engine bay (turbo/DP) cool with the race file and the high temps this summer. Will switch back to closed vents when it cools down for winter.

From the the extremely low CFs I have been seeing, either the cooling effect/octane bump is sufficient or the file is not really that aggressive. My feeling is that Direct Injection benefits greatly from the enthalpy change due to the ethanol's 3x higher heat of vaporization. It must be cooling the cylinder temps down quite a bit. I also recently came across a mention that the octane bump from ethanol is not linear but has diminishing returns with increasing concentration. E20 may be giving us a much bigger bang for the buck than say an E30, 40, or 50.

As opposed to making a custom tune for a specific fuel, I'm tailoring the fueling to the OTS tune.

PS: The advanced timing really works well with this engine since we have limited boost and fueling. The car just driving around is so much more responsive and lively. After feeling how nice a little extra advance runs I'll do anything I can to not go back to a pump file.

MKV727 said:

I'm waiting to run out of gas to try this myself, I didn't forget about it.

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:evil:

junker said:

PS: The advanced timing really works well with this engine since we have limited boost and fueling. The car just driving around is so much more responsive and lively. After feeling how nice a little extra advance runs I'll do anything I can to not go back to a pump file.

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X2. This engine loves Ethanol it fits it well except are limited fuel system. Ive been blending approx 25% E-85+93 for over 1 year now with race gas tune. The area you have to watch is too much timing advance @ peak tq (should be single digits no more ) and running to rich of lambda will make it knock. I've yet to see ANY timing pull. Once I see a PROVEN fueling upgrade that won't run out of fuel ill make hardware upgrade and have a custom tuned. People reading this with stock rod engine make sure you log and stay conservative on the tune. At first because with using E-85 comes very high cyl pressure( this is what makes the extra power ) and stock wrist pins don't take well. With a 25% blend your prob good just want to warn people , engines break because people get greedy lol and Ethanol dosnt show signs things are at that point then its too late. Bob. G :thumbsup: