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Discussion Starter · #1 ·
I was talking to a friend of mine that has a SC corvette (1100HP) and we were discussing E85 fuel. He said when he runs E85 $1.80/gal he got over 100HP more (1240HP).

From the research I've done, everyone seems to think that us FFV owners can't use E85 with the Magnuson and that it has to be 91 or 93, so I was surprised that my friend stated that we should be able to use it.

Now, the Tundra ECM should recognize what gas is being used and adjust tables normally and since the truck is already set up for E85 it shouldn't be a problem with the SC

Q - is anyone that has a Magnuson SC on a Flex Fuel using E85 gas? My assumption at this point is that as long as you're mapped for it (E85) you should be able to use it.
 

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you would need a tune, and a drastic amount of increased fuel. Its true the power would be pretty awesome, but my guess is you'll blow it up.
 

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What J said.


When you can tune PROPERLY for E85, it can increase power by as much as 15% from what I have seen on the big 3.

A Scat Pack I know went with an E85 tune, and he gained 80hp, this is on an NA engine. On a dyno. No bs.


But unless you can tune for it, you are just asking for problems. The flow of the injectors, along with controlling that, the fuel pump, etc... All that comes into play.
 
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I was talking to a friend of mine that has a SC corvette (1100HP) and we were discussing E85 fuel. He said when he runs E85 $1.80/gal he got over 100HP more (1240HP).

From the research I've done, everyone seems to think that us FFV owners can't use E85 with the Magnuson and that it has to be 91 or 93, so I was surprised that my friend stated that we should be able to use it.

Now, the Tundra ECM should recognize what gas is being used and adjust tables normally and since the truck is already set up for E85 it shouldn't be a problem with the SC

Q - is anyone that has a Magnuson SC on a Flex Fuel using E85 gas? My assumption at this point is that as long as you're mapped for it (E85) you should be able to use it.
I will jump in on this and explain it the best I can based on how other vehicles with blowers added on work since I don't have the ability to see what changes are made for the tune, but the components used should at least tell you if its possible.

First off, IF you have access to TRUE E85 (85% ethanol, 15% gasoline), to achieve the SAME power level as you did before on gasoline, it requires approximately 35% MORE fuel system capacity. Keep in mind, this isn't factoring in gains with adding timing or boost, this is just targeting the same horsepower level. Why this matters is typically the injectors, fuel pump and sometimes fuel lines/system aren't able to support the gains. When you do a Whipple or Magnuson kit on a GM or Ford, flex fuel is disabled and the truck is programmed to only run on 91 octane unless a custom tune is otherwise done.
Here is the math portion of this. If your truck makes 525 horsepower with the supercharger kit and an otherwise stock Tundra, to support E85, your fuel system must be capable of supporting just over 700 horsepower. While I haven't scanned a Tundra to see where the duty cycle on the injectors is (basically what percentage of their max flow are they at), nor have any information on the pump, but depending what size injectors the kit includes, what flow rate the pump is, what pressure it is capable of being run at, and how large the lines are, will tell you whether or not this is possible. As you add mods like exhaust, intake, headers, or increase boost and timing, your horsepower increases, as will the fuel demand. I always target AT MINIMUM 10% over the horsepower requirement before I get into tuning E85 vehicles, or doing a conversion as not having AT LEAST a 10% buffer is asking for trouble considering pumps will flow less when warm, or at lower fuel tank levels, warm fuel, and also keep in mind with a return-less style fuel system, fuel demand isn't instantly met with regards to how fast a roots blower makes power (instant power and sometimes up to a second before the fuel pump can increase pressure to compensate for the rails being drained with the instant fuel demand).

Second - to MAKE more power with E85, you have to either increase timing, or increase boost. The cooling effect of the alcohol will lower combustion temperatures and create a cooler charge, however that isn't seen at the intake air temp sensor, which is what controls timing, so gains are minimal (although SIGNIFICANTLY safer due to the cooler air charge, and octane rating of Ethanol). Methanol systems cool the actual air charge, which in turn allows the computer to adjust pending the sensor is downstream of the meth nozzle. One possible benefit you might see is if your truck currently pulls timing via Knock sensors, is the increase octane of E85 will cure any pinging issues and restore power to what the calibration desires. With this in mind, obviously if you spend the money on a fuel system to support E85, you want the ability to add timing, or add boost, to reap the rewards and benefits. TO MY KNOWLEDGE, none of the current systems offer tuning of the alcohol modifier tables only (ive emailed many of them, of those who responded, they said it is a global timing adder). What this means, is if you increase timing for the E85, it likely wont pull the timing if you go back to gasoline, which is the whole purpose of having a Flex Fuel vehicle. When I tune the GM and Ford Flex fuel vehicles, I dial the car in on gasoline, then have them come back after a couple tanks of E85 and only tune the alcohol tables to add timing/fuel as needed for the given alcohol percentages. This allows the tune to be safe on both, where as the current method of just adding timing for power will have to be removed for gasoline (multiple tunes or maps depending on what tuning system youre using). Same goes for adding boost as while 3-4 lbs would be fine on E85, if you went back to gasoline, you would have to change pulleys, and before going back to E85, make sure your tank is near empty, or run a few tanks through it before reinstalling the pulley or E85 tune.

Third - E85 is NOT consistent anymore. All our pumps in AZ say E50 minimum... while you may think it is a minimal difference, its actually a difference of running mid to high 90s octane, vs the 108-109 that true E85 carries. With regards to timing and boost levels, if you dial the truck for E85 and get a tank of E50, its likely your engine will be short lived as the knock protection of E85 is gone and detonation will likely occur since to my knowledge, the tuners aren't able to modify the flex fuel timing adders by alcohol percentage, so it wont pull timing for less ethanol. You can purchase an alcohol content kit that tests a fuel sample before you fill up, and adjust your truck accordingly, but keep in mind its going to mix, so if you get a tank of E85, and your current tank is either unknown, or E50 etc, compensate accordingly on timing and boost levels.

So to follow up on this, unless youre ready to REALLY pay attention to EVERYTHING, its a bad idea to go E85 on a boosted application without being ready to spend the proper money on a fuel system, tuning, and be ready for the consequences of accidental mistakes such as the wife/friend filling your truck up, thinking it might be "ok for a while" since you couldn't find an E85 station, or a tuning issue where the gasoline tune didn't take and left the timing in. It will only take seconds for a catastrophic failure to have boost or timing levels meant for E85 while running 91 octane. IF you decide to go down this route, youre going to need to research what size injectors work at the fuel pressure the Tundra runs at, how to tune the computer for those injectors, a pump compatible with the factory computers variable speed (or an aftermarket voltage booster that works off a boost switch), and of course verification which ever device you have for tuning will actually work.

Another option that is much easier, or can be used in conjunction with, is purchasing Torco race fuel additive. Pending youre doing the above, measuring ethanol content before filling up, spent the money on the proper fuel system etc, the flex fuel portion of the truck will at least adjust air fuel ratios for gasoline. When you cant get flex fuel, use Torco additive to get your octane rating. Unfortunately to get a similar octane rating to E85, it will require one can per 5 gallons (gives about 105 octane when added to 91), and at $21 a can, that's a lot for a full tank, but the general use is getting your truck to an E85 station, or for use when you aren't able to remove the tune/pulley and are low on fuel. Purchased in bulk (5 gallon pail, or 55 gallon drum), it gets significantly cheaper. E85 is Hygroscopic, meaning it absorbs water, so leaving it in your tank for more than 2-3 weeks is also a problem if you've dialed your truck in to the max level on a dyno, and any loss of octane could cause problems. Any time I store an E85 vehicle, I do it on gasoline, and in the case of my older race cars that weren't flex fuel, I switched them to race gas for storage.

While my intention isn't to talk you out of E85 (my other thread might seem like im attempting the opposite), I don't believe an application such as the Tundra is everyone. Ive been working with it for about 12 years now, and mostly converting non flex cars to E85 on factory computers for boosted applications, so ive seen a lot of the problems with people doing it and not being physically "connected" to the operation of their vehicles. Even though our trucks are Flex Fuel, the tuning ability isn't there like it is on domestic vehicles where you can just forget about it and let it take care of itself. Even on domestics, you really cant add boost safely unless you can pull timing enough on gasoline to keep the engine safe, so most of the gains are done via timing increase. On my last Cobra, it made approximately 200 horsepower more than on 91 because I was able to add 7 lbs of boost AND add significantly more timing, however I had to change pulleys and tunes to go to 91, or add race gas and put a gasoline tune in to leave the pulley on. It wasn't a big deal because I had 3 tunes stored in my programmer, and the tools to change pulleys/belts in the parking lot in 5 minutes in case I couldn't find E85. I also carried two 5 gallon fuel cans in the trunk with E85 around.

Hope this helped!
 

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Discussion Starter · #6 ·
Great Write up, FinixMike! Since my 13 is a Flex Fuel, I don't have to change the injectors or the fuel pump on my SC Install (Going in on Friday). I just thought there were some pretty interesting gains my buddy makes in his corvette with E85 fuel. I'm just going to run 93 in my Tundra and get DAP Tuning to smooth out the curve and remove Torque Management. Since I have a circuit in the truck that automatically disables all the nannies on startup I'm hoping to get about 550hp and about the same in torque...we'll see!
 

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Great Write up, FinixMike! Since my 13 is a Flex Fuel, I don't have to change the injectors or the fuel pump on my SC Install (Going in on Friday). I just thought there were some pretty interesting gains my buddy makes in his corvette with E85 fuel. I'm just going to run 93 in my Tundra and get DAP Tuning to smooth out the curve and remove Torque Management. Since I have a circuit in the truck that automatically disables all the nannies on startup I'm hoping to get about 550hp and about the same in torque...we'll see!
Once youre all done and dialed in on gasoline, try to get a hold of a scanner and see if you can log your injector duty and pump duty cycles. Im not sure what size the factory Toyota flex fuel injectors are, or the factory flow rate of the pump, but if the duty cycles of either are above 60% at wide open throttle (likely they will be closer to 90% due to the increased consumption with the supercharger) then you wont be able to run E85. This is typically how all the GM and Ford vehicles are once a blower is added to the flex fuel trucks and uses the factory injectors. Most of the ones I do custom tunes for are sitting at 90-95%, with some having run out of fuel and needing the shift points pulled back to compensate, or boost reduced to keep the AFR safe. I don't know about the market for aftermarket injectors/pumps, or the ability to tune for them, but for the domestic guys, I ALWAYS push going for larger injectors up front, knowing most will want to tinker later.
 

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Discussion Starter · #8 ·
Once youre all done and dialed in on gasoline, try to get a hold of a scanner and see if you can log your injector duty and pump duty cycles. Im not sure what size the factory Toyota flex fuel injectors are, or the factory flow rate of the pump, but if the duty cycles of either are above 60% at wide open throttle (likely they will be closer to 90% due to the increased consumption with the supercharger) then you wont be able to run E85. This is typically how all the GM and Ford vehicles are once a blower is added to the flex fuel trucks and uses the factory injectors. Most of the ones I do custom tunes for are sitting at 90-95%, with some having run out of fuel and needing the shift points pulled back to compensate, or boost reduced to keep the AFR safe. I don't know about the market for aftermarket injectors/pumps, or the ability to tune for them, but for the domestic guys, I ALWAYS push going for larger injectors up front, knowing most will want to tinker later.
Not sure you saw another post I commented on but someone had an issue with a Flex Fuel SC. What he stated was he put the green injectors in (removed brown ones) and had all sorts of CEL issues. I recommended by already knowing that the Magnusun SC doesn't come with new injectors or a fuel pump - most likely bc they are larger with increased flow rate for E85. Well, he did put the old injectors back in and everything he said is now normal.
Q:
Do you know what difference (specs) there is between green Tundra injectors and brown Tundra injectors?
Since you seem very knowledgeable, can you recommend a scanner that won't break the bank? I may need one for DAP Tune since I will be removing the Bully Dog after tune, but I'm thinking I'll want to do some logging to understand the best performance setup.

TIA
 

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Not sure you saw another post I commented on but someone had an issue with a Flex Fuel SC. What he stated was he put the green injectors in (removed brown ones) and had all sorts of CEL issues. I recommended by already knowing that the Magnusun SC doesn't come with new injectors or a fuel pump - most likely bc they are larger with increased flow rate for E85. Well, he did put the old injectors back in and everything he said is now normal.
Q:
Dow you know what difference (specs) there is between green Tundra injectors and brown Tundra injectors?
Since you seem very knowledgeable, can you recommend a scanner that won't break the bank? I may need one for DAP Tune since I will be removing the Bully Dog after tune, but I'm thinking I'll want to do some logging to understand the best performance setup.

TIA
Im pretty new to the Toyota world so I haven't really jumped into scanners to see which ones can see the Toyota PIDs, but id imagine someone on here has tried the simple autozone/oreillys generic scanners or some of the lower end large tool company models (snap on, blue point, etc). I will look into it further as I will eventually need one, I just work a ton and haven't really focused much on that side of it yet.

As far as injectors, I will sneak under my hood later if I get time and try to get a part number to cross reference. Injectors cant just be swapped unless the computer is properly programmed for them. As far as flow rate, they are labeled usually at a given CC or lbs of flow at a certain fuel pressure, however I also haven't looked into fuel pressure on these trucks. When installing my intake the other day, I did notice it uses a vacuum referenced return style regulator, which means likely it can be manipulated, and possibly boost referenced, but without knowing a base pressure without the vac attached, its tough to calculate injector flow unless its on the website. In the GM and Ford world, injectors are often swapped between vehicles and even across brand lines, so most values are commonly known and/or displayed online for tuning purposes, but I imagine the Toyota world is going to be different as a quick search yielded zero results.

See if DAP has any recommendations for you on a scanner, if I get time this week/weekend I will look into the injectors.
 

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Im not sure what size the factory Toyota flex fuel injectors are, or the factory flow rate of the pump, but if the duty cycles of either are above 60% at wide open throttle (likely they will be closer to 90% due to the increased consumption with the supercharger) then you wont be able to run E85.
Canada does not have flex fuel Tundras for sale, so I have no info on anything related to them.
I tested the stock S/C pump to flow 305 LPH with no outlet restriction.
My Aeromotive 325 tested at 319 LPH with no outlet restriction.
http://www.tundratalk.net/forums/tu...tions/508458-christmas-came-early-year-2.html
The injector duty cycle is at 98% at high RPM with just a smaller S/C pulley installed.
I use the Toyota Techstream to do my data logging.

As far as injectors, I will sneak under my hood later if I get time and try to get a part number to cross reference. Injectors cant just be swapped unless the computer is properly programmed for them. As far as flow rate, they are labeled usually at a given CC or lbs of flow at a certain fuel pressure, however I also haven't looked into fuel pressure on these trucks. When installing my intake the other day, I did notice it uses a vacuum referenced return style regulator, which means likely it can be manipulated, and possibly boost referenced, but without knowing a base pressure without the vac attached, its tough to calculate injector flow unless its on the website. In the GM and Ford world, injectors are often swapped between vehicles and even across brand lines, so most values are commonly known and/or displayed online for tuning purposes, but I imagine the Toyota world is going to be different as a quick search yielded zero results.
Stock S/C injectors are rated at 450 - 480 cc/min
There are upgraded ones from Five-O motorsport that flow 550 cc/min
As you mentioned, the ECM would have to be tuned for those.
https://www.ebay.com/itm/8-550cc-Fu...iser-5-7-325lph-Fuel-Pump-600-HP/271965920347
The stock fuel pressure is a constant 42-43 PSI, since the regulator is referenced to atmospheric pressure in the intake pipe.
I did play with referencing it to the boost port when I was running my 50 hp dry shot of Nitrous.
It worked fine, but these trucks already run so rich (10:1 AFR on stock tune at high RPM/load), that referencing it to boost caused it to run below 9:1 AFR and robbed power.
 

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These trucks run rich on the supercharged tune because the knock sensor is picking up Knock, on both the factory tune & the magnuson flex tune. That’s why you’re seeing 10’s. Dap has already proved these things run out of fuel with just the small pulley due to the pump, hence why the 320aero pump or a boost a pump by kenne belle is needed. The factory flex fuel injectors are larger than the fit kit injectors but not by much if I remember right.


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These trucks run rich on the supercharged tune because the knock sensor is picking up Knock, on both the factory tune & the magnuson flex tune. That’s why you’re seeing 10’s. Dap has already proved these things run out of fuel with just the small pulley due to the pump, hence why the 320aero pump or a boost a pump by kenne belle is needed. The factory flex fuel injectors are larger than the fit kit injectors but not by much if I remember right.


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Where are people installing the KB pumps?
 

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Where are people installing the KB pumps?


At the harness in the engine bay to my knowledge. I haven’t done one so I can’t comment more than that.
 
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These trucks run rich on the supercharged tune because the knock sensor is picking up Knock, on both the factory tune & the magnuson flex tune. That’s why you’re seeing 10’s.
The ECM only retards ignition timing to suppress knock.
The knock sensor output has no effect on air fuel ratio.
The ECM actually has no idea what AFR the engine is operating at when it is under WOT.

Dap has already proved these things run out of fuel with just the small pulley due to the pump, hence why the 320aero pump or a boost a pump by kenne belle is needed.
The injectors are the limiting factor of the fuel system, not the pump.

8 injectors * 480 cc/min * 60 min = 230 lph
The stock S/C pump flows about 300 lph
 

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Where are people installing the KB pumps?
The boost-a-pump is a step up transformer that increases the voltage to the fuel pump.
It is not an actual fuel pump in itself.
 

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The ECM only retards ignition timing to suppress knock.

The knock sensor output has no effect on air fuel ratio.

The ECM actually has no idea what AFR the engine is operating at when it is under WOT.

That’s correct, but while it’s pulling timing, it’s dumping the same amount of fuel, which Is why if you have a wideband it drops to the 10’s and never comes back up until a shift.
 
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