Red Pill, Blue Pill, Green Pill?

[Swordsmith]

Over in the April MPG competition thread some unrelated questions came up, I thought maybe they deserved their own thread instead of cluttering up the competition one.

Repeating the basics; Trifecta has among their many versions of the tune one designed to allow the 1.4T to run E85, a blend of 85% alcohol 15% gasoline, which is roughly the equivalent of 106 octane. This, coupled with replacing the fuel injectors with larger ones capable of delivering more volume, can result in significantly more power.

So significant was the power boost, in fact, that when Vince released the tune he commented that he'd been forced to hold it back from its full potential since the stock clutch could not hold that much power. Jokes were made referring to this full power alcohol tune as the "red pill"

I jumped off the deep end of insanity, got an experimental clutch from Clutchmasters, and got Vince to send me a blue pill/red pill selectatune, and have been experimenting with it on and off ever since.

Burned out the experimental clutch, have had that upgraded to a new even stronger one.

I also installed an alcohol sensor, and the tune is intelligent enough to allow me to run anything from 87 octane gas to premium to E85 and to mix any amount of the above together.

My initial conclusion is that E85 delivers more power, and that the red pill delivers more power than the blue pill, similar to the difference between the performance and eco versions of the regular Trifecta selectatune.

E85 also sucks. In cold weather I have a hard time starting, and frequently stall, until my engine gets over 100F or so. And gas mileage is about 2/3rds that of regular gas in the same engine same tune same conditions; 22-23mpg rather than 30-33mpg. It is cheaper than regular gas, but not by a factor large enough to make up for the lower efficiency.

What this means for me is that I've built a car that's a little hot rod when I want one, but still reasonably economical if I'm willing to sacrifice and put gasoline in my tank.

E85 is also much greener, even allowing for the larger volume of fuel used, emissions per mile are much lower, and you're not using up nearly as much fossil fuel.

This may or not be an intelligent question, but if the E85 injectors/tune you are using allow you to be "flexfuel" and there are a bunch of flex fuel vehicle on the road that don't swap out injectors, why would you have to?

Engineering is often a series of compromises, perhaps the smaller injectors are more efficient but you need to use bigger ones to fully flow the amount your engine can use on E85. Or perhaps not, I don't know, I'm just questioning. I -seem- to be getting worse mpg even on 93 since I changed over but there are many variables that haven't been controlled for so I can't tell which are which.

I did for a little while run a special version of the flexfuel tune set up for the standard injectors, it just wasn't really ready for prime time so I had to keep a light foot. It is possible though, and one thought is there might be a "green pill" version of the tune which would allow for E85 but be more fuel efficient. If so, and if the most attractive thing about E85 for you is the corn fed cred, this might be something we can talk Vince into doing, I wouldn't think it would take much.

And the Red pill, what do I need to do my Auto to be able to handle it? I know I have read at least in one place that the stock Auto can handle more power than the stock Manual, since you are up on all of this, has anyone posted anything about these conditions/facts in numbers form?

I remember seeing the same thing posted, but I haven't seen facts per se. The concern isn't specific to a red pill/alcohol setup, it is purely one of torque and how much force the clutch can hold; the red pill is just one way to get well over that limit. If, then, we could find a number for how much force the auto can hold, you could work backwards and get your answer there.

 

[Swordsmith]

The #42 Injectors... Are there any other E85 injectors available? I would hate to lose efficiency on reg gas.... My RS already has an efficiency problem.. Little gears.

Although BNR offers those injectors as E85 injectors, they are really just bigger injectors that fit the Sonic. Even the stock injectors work, they just don't deliver much volume.

See alcohol has less energy per unit volume, so you have to pour more in to get the same size "explosion". But it allows you to run much faster timing without knock, which means that if you can deliver enough liquid you can get a lot more power, larger number of same size "explosions" per second.

Without bigger injectors, your maximum power is reduced.

Speculation, which I haven't seen backed up by facts yet, is that the larger injectors might be inefficient at delivering small amounts of fuel, so that when you are running low power you might be using more than you need. This in turn MIGHT mean that this hypothetical "green pill" setup using stock injectors and E85 would give you power similar to a Trifecta tuned car running 93, but perhaps not suck quite so badly at mpg. Who knows, maybe we could get 25mpg, or even better...

And maybe we could get better than 33mpg while running gasoline, I know before I started doing all these conversions I got as high as 44mpg. Many variables though, wheels tires, intake, exhaust, clutch, weather, driving conditions... I do not have clear data on what extent the 42# injectors are affecting things.

 

[Eric Smit]

Stock injectors are 28# and the "E85 injectors" are 42#.

 

[Macehammer]

Thanks for the clarifications.

I'm interested in all of this. I don't entertain the idea of running E85 often, but I would like the option, especially if on occasion, I would like to go "balls out", to use the parlance of the time.

But in making that decision, I don't really want to sacrifice mpg on regular gas... Now I know a lot if folks might say certain sacrifices need to be made, and maybe that is true, or maybe all the options just haven't been exhausted yet....

Recently I am averaging 36.5mpg babying it on 87oct, Shell winter gas. I think this is considerable in the RS, because I drive uphill a lot, with some city traffic, and its only avg rated at 38hwy. It would be a shame to lose that capability.

Another great reason to ponder this, as was mentioned, is my Auto doesn't need a clutch upgrade to run red pill, apparently. So it's a big power upgrade, for pretty cheap $$.

I don't know if Vince or BNR are gonna view this thread, but I am looking for options to conservatively push the envelope here.

Does anyone have any other info, prospects, possibilities?

 

[River_Rat]

Maybe the sweet spot for a "green pill" would include

36# injectors(28% more than stock) or

39# injectors (39% more than stock)

as opposed to the 42# injectors (50% more than stock).

However, I presume 1) that there are more factors to consider than flow rate alone and 2) that there is a reason the 42# green giants were selected in the first place.

 

[Swordsmith]

If Mace is getting 36.5mpg babying it, and I'm getting 33mpg charging up onramps and driving 80mph while carrying 1000 lbs [cargo plus humans] using the same 87 octane gasoline, maybe the 42# injectors aren't an issue after all.

In order to switch between alcohol contents, there are several necessary steps:

One, you need to tell the ECU how much alcohol there is. You can either do this by nearly draining your tank and swapping fuel, and swapping tune (tunes can be written to fake any given level of alcohol) or by installing an alcohol sensor and using a tune that can read it and adjust on the fly. The Sonic ECU is set up for this, so it's easier than it sounds, cost will be whatever you can find as a price on a sensor, plus the time and small misc parts to do the install.

Two you need injectors big enough to deliver the volume you intend to use. With stock injectors I don't think you'll really see much if anything in the way of power gain, since there's only so much liquid they can shoot into the cylinders. I don't know how scientific the selection of 42#ers was, Jerry at BNR offers them as E85 injectors and they do the job, but there are other sources and other sizes and maybe something else will work better. Not sure how to find out other than experimentation. Swapping them in is easy enough and gets easier once you've done it a time or two.

Three you need access to E85. Nearest pump to my house in PA is under a mile away... but I'm lucky, there aren't many pumps around there and if I travel any distance I end up putting some regular gas in; no problem with the sensor but pretty annoying if it means having to swap tunes, particularly since you get crappy performance when you have a gallon or two of one fuel left while running a tune designed for the other fuel, pure.

Here in Waxahachie it looks like my closest E85 pump is 25 miles away, not as handy.

Then, to run the "red pill" you need a clutch that will hold that much power. Sounds like there you're lucky, if the auto tranny can handle it you don't need to debate the "red pill vs blue pill" consideration. Blue pill E85 tune is already more powerful than running anything but race gas (which can blow your clutch without needing a special tune) but it doesn't seem any better for purposes other than not blowing up your car.

 

[Eric Smit]

with my current results, I'm fairly certain the 42# green giant injectors aren't ruining gas mileage. it's not like these are 1000cc injectors here.

 

[River_Rat]

You are probably correct, but I still suspect that 42# might be overkill for the tiny 1.4. Admittedly, I know little to nothing about the duty cycle data. Just saying that it is a huge jump.

 

[Macehammer]

Swordsmith, also to note, I am losing mpg on my auto, because automatic. If I were to "baby it" in a manual RS, or as some might call it I bet I could get damn close to topping 40mpg(38-39mpg).

So stomping on it with #42 injectors, you are losing maybe 6-7mpg to tuned stock injectors, not scientific.

I think i am gonna agree it's the lead foot, not the injectors...


I live in the Harrisburg, PA area, there are several e85 distributors in around that area, and some along my route to work. The geography isn't my primary concern. The $300 isn't prohibitive to me, though I would want the sensor, too, but it is prohibitive if I would lose mpg (on reg gas).

How difficult was the sensor install? Keep in mind mucking about in fuel lines isn't my forte.

 

[SPOTWORK]

correct me if I'm wrong but I could I slap in the #42 injectors and not run E85, instead use 91-94 octane to get the most out of the car when I hammer down. Yet when I'm being a good boy cruising for gas mileage the duty cycle of the injector would be 5-15% still giving me a formidable 40 mpg

 

[laborsmith]

I asked Dave Michel that very question over two years ago.

I did not get a positive answer.

Dave was Vince Geglia's 42lb and 60lb injectors source back when Trifecta first started work on specific e-85 tuning.


Laborsmith

 

[Preloader]

correct me if I'm wrong but I could I slap in the #42 injectors and not run E85, instead use 91-94 octane to get the most out of the car when I hammer down. Yet when I'm being a good boy cruising for gas mileage the duty cycle of the injector would be 5-15% still giving me a formidable 40 mpg

Vince G tested that hypothesis last week on the dyno and saw a gain of a couple hp. He did not do MPG testing.

Smit claims that you can get close to the same MPG with the 42# as you can with the stock 28#.

 

[Eric Smit]

I'm currently using 42# injectors for my MPG run for this contest.

 

[Swordsmith]

Larger injectors will let you get a little more power out of regular gasoline, but the limit there becomes one of how much boost you can generate. E85 requires a larger volume of fuel to get the same power per "explosion", so it needs the bigger injectors at much lower boost levels.

I'm guessing that the stock injectors are just a little short of enough to deliver all the fuel you can burn at 22psi, since they are optimized for 12psi max boost which is what the stock tune delivers. The 36# ones someone mentioned elsewhere would probably be plenty for this effect, if that logic is correct. However, if we aren't seeing any appreciable loss due to running 42#'s then there's no real reason not to go ahead and sub those in.

 

[Swordsmith]

How difficult was the sensor install? Keep in mind mucking about in fuel lines isn't my forte.

The sensor install is very easy. There is only a single fuel line involved, if you open up your hood you can see it there right out in the open. Best thing to do is replace the whole line (its less than 3 feet long) with two new ones made of alcohol resistant fuel line, with clips at each end. You unclip the current line, clip one end of your new lines to each of the spots you unclipped from, and clip the sensor in the middle. Find a spot on the back wall of the engine compartment to screw the sensor to, and you're physically installed. Then the tricky part, you have to wire in to the ECU, which consists of getting a couple pins that fit the sockets, and doing a splice for ground. That part is much harder than the fuel line you were worried about. But it's still dead easy.

Once installed the sensor won't do anything without a tune, but it also won't interfere with anything while you get around to getting the tune.

Here's the install thread

 

[NewZJ]

If we are interested in the blue pill with sensor install and never plan in upgrading the clutch, do we really need the 42# injectors?

I assume red pill would use every bit of the 42# but with blue being less output I would guess that it could still not be limited by smaller injectors (bigger than stock but less than 42#)

 

[Swordsmith]

Hasn't really been determined yet, but I imagine the answer is that the full 42# isn't needed. On the other hand, it is starting to look like they aren't hurting anything, and they are readily available from BNR, as opposed to having to hunt something down yourself and making sure they are compatible.

The only way to be sure would be to get a set of the ones available and try each with a variety of tunes and fuels.

If there's a difference in MPG going from smallest to largest, then there would be a reason to look for the smallest injector that gets the job done.

If there's a difference in hp going from smallest to largest, then there would be a reason to look for the largest injector that still shows a gain over the next smaller one down.

All we know now is that the 42#'s are showing an increase in hp even on a tuned stock sonic running gasoline, and that the stock injectors are insufficient to run even a blue pill E85 at WOT (although they work fine at lower power demands)

And we think the 42#'s can't be costing much if any MPG, because Smit is a hypermiling fool and surely he'd know by now if they were costing him anything.

If there's no down side to running 42#'s then there's no real reason to consider the middle sizes, it's either keep the stock ones or go all in.

Which makes me wonder about the 60# ones... maybe 42# is more than enough for blue pill but 60# would be better for red... if there's no down side to bigger, why not?

 

[Macehammer]

Or maybe the #39s are sufficient and have a small mpg gain...

 

[NewZJ]

Is there a cost difference in injector sizes?

 

[Eric Smit]

I'll let you know if 42# injectors have a huge detriment in MPG.