e85 on N/A setup? LS3
Thread Starter
Le Mans Master
Joined: Dec 2013
Posts: 6,337
Likes: 5,109
From: Charles Town WV
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e85 on N/A setup? LS3
Almost afraid to ask this here but here goes. Anyone running corn on an N/A LS3 setup? Worth it at all? Any substantial gains to be had? Stock pump and injectors enough? Have a flex fuel sensor and harness laying around from my C5 build... just debating if its worth doing it. Car is a GS a6 Car and just planing on a mild cam only build.
Burning Brakes
Joined: Jan 2019
Posts: 1,209
Likes: 215
From: Dallas, Tx
well I know of 2 cars that did it 1 was a 2010 SS camaro which only had CAI and full exhaust and picked up 24 rwhp by switching to E85 and my sons 2017 Camaro SS picked up 30rwhp and 20rwtq so if your just looking for a little more power and the fact that your able to run both E85 and 93 pump then yes its worth it and as you add more performance go fast parts especially Forced induction then for sure its a benefit
Heel & Toe
Joined: Jun 2018
Posts: 19
Likes: 5
There's not much gains to be had if you're tuned on 93 going to E85. Honestly it all depends on how your car was tuned on pump gas too. If you have a conservative tuner with 93 or run 91 you will see a little more going to e85.
Pro
Joined: Jul 2013
Posts: 509
Likes: 62
Really depends if you are knock-limited or not.. If you can achieve maximum torque timing now without knocking, you won't see many gains from E85. To do E85 right, you want to install the flex fuel sensor so that your car will adjust for various blends of gasoline and ethanol. You will also probably want more injector and possibly fuel pump as well. I'm around 80% on stock LS3 injectors and stock pump (but I'm also H/C/I/E/meth). I don't remember where I was cam-only.
If you are knock limited, E85 may well be your answer, but I would look at 50/50 methanol injection as an alternative. In addition to the octane bump (not as good as E85, obviously), you will dramatically lower your intake air charge temperature (usually down to 10 degrees below ambient or so), which also allows you to run more timing without risk of knocking.
If you are knock limited, E85 may well be your answer, but I would look at 50/50 methanol injection as an alternative. In addition to the octane bump (not as good as E85, obviously), you will dramatically lower your intake air charge temperature (usually down to 10 degrees below ambient or so), which also allows you to run more timing without risk of knocking.
Le Mans Master
Joined: Apr 2013
Posts: 5,376
Likes: 1,118
OP: since you have the flex fuel sensor kit and harness already, I would go ahead and install it. It’s pretty easy to do, once you have the correct pin out for the E38 ECM. E85 has around 30% oxygen by weight, so there’s no way that you’re not going to see some gain from it, especially if you tune it properly for E85, which doesn’t take a lot. The DSX kits don’t cost much for the quality parts you get, and are as easy to install and the tune really only needs a little bit of tweaking, so I don’t understand why anyone would say it costs so much.
You can look at it this way: you’re going to see more of a power gain from it than you would see from installing a “CAI”, for less money, and a little less hp than headers would give you, for a whole lot less money. And those two things are pretty much the most commonly installed parts on these cars.
You can look at it this way: you’re going to see more of a power gain from it than you would see from installing a “CAI”, for less money, and a little less hp than headers would give you, for a whole lot less money. And those two things are pretty much the most commonly installed parts on these cars.
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,684
From: Southeast TX
If you really want to take full advantage of E85 in an N/A setup, you need to up the static compression ratio. You can get upwards of 12:1 with aftermarket heads that have 12 or 13* valve angles. You can mill them quite a bit more than stock heads before getting into PTV clearance issues.
I recently went from stock LS3 to adding a mild cam, CNC ported and milled stock heads, thinner head gaskets, ported and rod modded intake manifold, LT headers, and a few other bolt ons. CR came in about 11.2:1. The cam has 0 overlap and drives really close to stock after a street tune by Pat G. It made just over 500 at the wheels.
If I had a bigger budget to work with, some milled PRC heads ($2600 vs the $750 I spent on porting and milling stock heads) would have provided a nice bump while still keeping the cam on the mild side. Gains from E85 would have been good too, but that added even more cost because I thought I would need injector and fuel pump upgrades. I applied for a grant from CI GS to do more extensive work, but was turned down because my paperwork was insufficient. Shoot.
I recently went from stock LS3 to adding a mild cam, CNC ported and milled stock heads, thinner head gaskets, ported and rod modded intake manifold, LT headers, and a few other bolt ons. CR came in about 11.2:1. The cam has 0 overlap and drives really close to stock after a street tune by Pat G. It made just over 500 at the wheels.
If I had a bigger budget to work with, some milled PRC heads ($2600 vs the $750 I spent on porting and milling stock heads) would have provided a nice bump while still keeping the cam on the mild side. Gains from E85 would have been good too, but that added even more cost because I thought I would need injector and fuel pump upgrades. I applied for a grant from CI GS to do more extensive work, but was turned down because my paperwork was insufficient. Shoot.
Burning Brakes
Joined: Jan 2019
Posts: 1,209
Likes: 215
From: Dallas, Tx
heres some nice I found useful from over on Camaro6
I bought the E85 sensor kit from Skidmark garage in the spring but didn't have the time to install it until recently. The kit wasn't too bad to install. There are a few potential gotcha's though.
I figured the fuel connection part would be the difficult part. It isn't. The fuel line is pretty easy to disconnect. What I did do before disconnecting it was to pull the fuel pump fuse and then run the car until the engine stopped. This depressurized the line. I remember changing the fuel filter on a VW and having fuel **** out everywhere. This avoids that.
The difficult part of the install is in adding the sensor wire to the ECU pin #38 connector. I thought the pin was seated, but it must go into the connector a lot deeper than I thought. The best way to verify if it is seated (it wasn't clear in the instructions) is to pop off the blue plastic mating shield to the connector. When you pop it off, you can see the actual pins and if they are seated correctly. The pin should be flush with the other pins.
If the pin is not seated correctly, the HP Tuners Scanner tool will return a constant value of 40% ethanol.. I trouble shooted everything by verifying voltage to the sensor (12 V) and also voltage from the white wire.. I was reading (0.3V) on the gas I had in the tank. The white wire reads from 0V to 5V. 0.3V is probably 7.5% ethanol or so. I ended up emailed Jeremy from Skid Mark and he helped me narrow it down to the pin not being seated correctly.
Anyway, once I got the white wire seated correctly the sensor finally returned a valid value.
Note. I did pay $499 for the HP Tuners suite. I can do a separate review on this later. As someone who is new to Chevy products, I'm not a fan of HP Tuners credit based model. So I paid $500 to tune 2 vehicles. Kind of a rip off.
But.. on to the good part.
E85 is awesome on this car. The basic tune I used which is a derivative of what I found on this board provides a noticeable increase in power.
Let's face it, the Camaro is somewhat of a gas guzzler. The MPG is good for a V8 engine for sure, but still.. I have averaged 20.5 MPG on premium unleaded. Typically premium unleaded for me has been about $0.70 - $0.90 more per gallon than regular unleaded ($2.85-$3.20).
My first tank of E85 from last week cost me $1.88 per gallon. I expected the E85 to be about 70% as efficient as regular gasoline. So far, I have averaged 17.2 MPG on E85 which would imply an efficiency ratio of 17.2 / 20.5 = 83.9%. I'm going to be conservative and call it 80%. If you use that number, I am paying a gasoline equivalent price of $1.88 / 0.80 = $2.35 per (100+ octane) gallon. Each tankful of gas I am saving anywhere from $10 - $15 per tank plus gaining 25+ hp and torque. So the mod will pay for itself after $750 / $12.5 = 60 fill ups (or roughly 20,600 miles of driving).
Once you do this mod, you will probably want to install the "GasBuddy" app on your phone. This will let you find the lowest priced E85. :-) Today I fueled up at $1.75 per gallon which is $2.18 equivalent! After lighting up the tires, I joked with my son about how we are "Green" now.
-John
I bought the E85 sensor kit from Skidmark garage in the spring but didn't have the time to install it until recently. The kit wasn't too bad to install. There are a few potential gotcha's though.
I figured the fuel connection part would be the difficult part. It isn't. The fuel line is pretty easy to disconnect. What I did do before disconnecting it was to pull the fuel pump fuse and then run the car until the engine stopped. This depressurized the line. I remember changing the fuel filter on a VW and having fuel **** out everywhere. This avoids that.
The difficult part of the install is in adding the sensor wire to the ECU pin #38 connector. I thought the pin was seated, but it must go into the connector a lot deeper than I thought. The best way to verify if it is seated (it wasn't clear in the instructions) is to pop off the blue plastic mating shield to the connector. When you pop it off, you can see the actual pins and if they are seated correctly. The pin should be flush with the other pins.
If the pin is not seated correctly, the HP Tuners Scanner tool will return a constant value of 40% ethanol.. I trouble shooted everything by verifying voltage to the sensor (12 V) and also voltage from the white wire.. I was reading (0.3V) on the gas I had in the tank. The white wire reads from 0V to 5V. 0.3V is probably 7.5% ethanol or so. I ended up emailed Jeremy from Skid Mark and he helped me narrow it down to the pin not being seated correctly.
Anyway, once I got the white wire seated correctly the sensor finally returned a valid value.
Note. I did pay $499 for the HP Tuners suite. I can do a separate review on this later. As someone who is new to Chevy products, I'm not a fan of HP Tuners credit based model. So I paid $500 to tune 2 vehicles. Kind of a rip off.
But.. on to the good part.
E85 is awesome on this car. The basic tune I used which is a derivative of what I found on this board provides a noticeable increase in power.
Let's face it, the Camaro is somewhat of a gas guzzler. The MPG is good for a V8 engine for sure, but still.. I have averaged 20.5 MPG on premium unleaded. Typically premium unleaded for me has been about $0.70 - $0.90 more per gallon than regular unleaded ($2.85-$3.20).
My first tank of E85 from last week cost me $1.88 per gallon. I expected the E85 to be about 70% as efficient as regular gasoline. So far, I have averaged 17.2 MPG on E85 which would imply an efficiency ratio of 17.2 / 20.5 = 83.9%. I'm going to be conservative and call it 80%. If you use that number, I am paying a gasoline equivalent price of $1.88 / 0.80 = $2.35 per (100+ octane) gallon. Each tankful of gas I am saving anywhere from $10 - $15 per tank plus gaining 25+ hp and torque. So the mod will pay for itself after $750 / $12.5 = 60 fill ups (or roughly 20,600 miles of driving).
Once you do this mod, you will probably want to install the "GasBuddy" app on your phone. This will let you find the lowest priced E85. :-) Today I fueled up at $1.75 per gallon which is $2.18 equivalent! After lighting up the tires, I joked with my son about how we are "Green" now.
-John
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Burning Brakes
Joined: Jan 2019
Posts: 1,209
Likes: 215
From: Dallas, Tx
If you really want to take full advantage of E85 in an N/A setup, you need to up the static compression ratio. You can get upwards of 12:1 with aftermarket heads that have 12 or 13* valve angles. You can mill them quite a bit more than stock heads before getting into PTV clearance issues.
I recently went from stock LS3 to adding a mild cam, CNC ported and milled stock heads, thinner head gaskets, ported and rod modded intake manifold, LT headers, and a few other bolt ons. CR came in about 11.2:1. The cam has 0 overlap and drives really close to stock after a street tune by Pat G. It made just over 500 at the wheels.
If I had a bigger budget to work with, some milled PRC heads ($2600 vs the $750 I spent on porting and milling stock heads) would have provided a nice bump while still keeping the cam on the mild side. Gains from E85 would have been good too, but that added even more cost because I thought I would need injector and fuel pump upgrades. I applied for a grant from CI GS to do more extensive work, but was turned down because my paperwork was insufficient. Shoot.
I recently went from stock LS3 to adding a mild cam, CNC ported and milled stock heads, thinner head gaskets, ported and rod modded intake manifold, LT headers, and a few other bolt ons. CR came in about 11.2:1. The cam has 0 overlap and drives really close to stock after a street tune by Pat G. It made just over 500 at the wheels.
If I had a bigger budget to work with, some milled PRC heads ($2600 vs the $750 I spent on porting and milling stock heads) would have provided a nice bump while still keeping the cam on the mild side. Gains from E85 would have been good too, but that added even more cost because I thought I would need injector and fuel pump upgrades. I applied for a grant from CI GS to do more extensive work, but was turned down because my paperwork was insufficient. Shoot.
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,684
From: Southeast TX
sweeeeeeet this exactly what I want to do to my 08 A6 Vette but with either a 3200 Circle D stall or maybe the Yank PAS 3400 or 3800 stall still undecided anyway when you said "mild cam" was it the GPI stage 1 or the Cam Motion stage 3 mild cam by chance? both have high LSAs and work well with stock converters and have a stock idle quality just curious
Racer
Joined: Oct 2012
Posts: 348
Likes: 28
From: Houston TX
I run flex fuel with a DSX setup on my H/C/I LS3. Made 506rwhp on a mustang dyno on E. 500rwhp on 93. The compression ratio isn't high enough to really make substantial gains. Its cheap for just the flex fuel kit but buying the bigger injectors makes it expensive.
Burning Brakes
Joined: Jan 2019
Posts: 1,209
Likes: 215
From: Dallas, Tx
Racer
Joined: Oct 2012
Posts: 348
Likes: 28
From: Houston TX
Same day same dyno. Tuner just drained the tank and filled it with E and made another pull with I think 6 more degrees of timing. I'd have to double check the ethanol timing adder table to confirm that number though.
Burning Brakes
Joined: Jan 2019
Posts: 1,209
Likes: 215
From: Dallas, Tx
Racer
Joined: Oct 2012
Posts: 348
Likes: 28
From: Houston TX
that's interesting ive read and been told a car like yours is going to pick up just as much going with E85 if not more than a stock car does whos your tuner if I may ask? not to bash anybody but a shop tuner probably has more time under their belts than a DIYer or handheld
Racer
Joined: Oct 2012
Posts: 348
Likes: 28
From: Houston TX
It makes sense though. If you have an efficient cylinder head that is not knock limited on power the only gain from E85 is the minor oxygen content in the fuel and cooler charge temps which are not a big deal on an NA motor.
Le Mans Master
Joined: Jun 2015
Posts: 6,326
Likes: 1,105
From: Austin Tx
6 degrees?? that's wild. I would scale that back, especially if it's not picking up any extra power.
Racer
Joined: Aug 2018
Posts: 458
Likes: 96
to make power with E85 on a NA setup you have to raise the compression ratio. You have to raise it so high in fact that if you try to run 93 you have Serious detonation. I think you have to be around 12.5 or 13:1 to make decent power on E85. Other wise youll maybe see 15-25
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,684
From: Southeast TX
to make power with E85 on a NA setup you have to raise the compression ratio. You have to raise it so high in fact that if you try to run 93 you have Serious detonation. I think you have to be around 12.5 or 13:1 to make decent power on E85. Other wise youll maybe see 15-25
Racer
Joined: Aug 2018
Posts: 458
Likes: 96
If you have a tuner with flex fuel experience and are equipped with flex fuel bits, you can run anything from straight pump 93 octane to full E85 without worry. The flex fuel sensor will alert the ECM as to what kind of octane you're running. The tune should adjust.
Your flex fuel tune wont be able to fix the fact you are running a high CR to make power on E85, and on 93 it will cause detonation.