2GR-FKS on 91 octane: 311hp@6400rpm and 280lb-ft@4800rpm

That 11.8:1 compression ratio seems to bode well for 91 octane making a difference. But I may be out of touch with modern engine CRs. I looked up the 1gr and its 10:1, and the 2gr-fe is 10.8:1. If only the 91 octane mod could be in the new cheap and free 3rd gen mods thread.

 

Now that people actually have them, just out of curiously what does the 16's user manual specifically say to use?

 

Has anyone heard of this issue with direct injection engines..?

Although Direct Injection provides more power and efficiency, a carbon build-up occurs in the intake valves that over time reduces the airflow to the cylinders, and therefore reduces power. Fuel contains various detergents and can keep the intakes clean. When fuel is no longer being sprayed in the intake valves, small amounts of dirt from intake air cakes on the intake walls, even with air filters that prevent most of the dirt from entering the cylinder.[67] This build-up can become severe enough that a piece can break off and has been known to burn holes in catalytic converters.[68] It can also cause sporadic ignition failures.[68] These problems have been known for some time and technologies[citation needed] have been improved to reduce the carbon build-up.

 

Toyota has a technology to specifically address that issue
http://wardsauto.com/vehicles-technology/toyota-advances-d4s-self-cleaning-feature-tacoma

 

He quoted an article speaking of valves becoming covered in carbon. That article is about the direct fuel injectors. Good article, though

To the asker, yes, the port injection will allow fuel to flow over the vales, cleaning the carbon off of them. The engine will rarely use just direct injection so port injection will be used at nearly all times. I believe direct only mode is when you have the pedal to the floor. Atkinson cycle will be a mix of port and direct.

 

I'm sure if you spun the 3.5 in the Tacoma faster than 6000rpm you would see an increase in power. With more aggressive cam phasing and a small yet safe bump in ignition timing, i dont doubt that you could get an additional 30hp. Generally horsepower increases with rpm as long as the cylinder head flow is adequate. Now, whether or not you can see those increases by just switching octanes is a whole different story. However, if any of my fellow Utah 3rd gen owners want to test this theory, I have a AWD Mustang Dyno at my shop.

 

Somebody takes up this good man on his offer and dyno the bitch!

 

I'm sure with our altitude and the fact that it's a mustang dyno, we will all get our hearts broken.

 

I hear that the entire engine is aluminum. Sweers said this. Is he correct?

 

Block, heads, timing chain cover, oil pan upper, pistons = aluminum
Head covers = resin
Crank, rods, cams, piston sleeves, oil pan lower = steel

 

It's not in Toyotas DNA. Part of their QDR is running the motor at a lower max rpm. I am sure it's capable of running a few hundred rpm higher like the Colorado.....for a shorter lifetime.

 

I ran 91 octane for the first time in my 2017 Taco with the 2GR-FKS. Needless to say I can definitely notice a difference. Does it have 30 more hp? No way. But it did seem to increase a bit. Acceleration is also smoother. I will be running high octane/ethanol free for awhile to see how it affects the 'learning' process of the ECM. I've heard it may need to go through a full tank to 'adjust'.

 

Might take a bit more than 1 tank. On my FJ, I ran a whole year on 87 and another year on 91. Tried to use the same gas station and even the same pump. I didn't have a dyno, but I did have my handy paper to do MPGs and after around 2-3 tanks (~500+ miles), the MPGs switched over which I figured was the ECU resetting. Could do something similar by pulling the battery cable but IIRC, the resetting process took longer (not sure anymore).

 

I have also switched to 91 to see how the mapping changes. The difference is 20 cents x's 18 gallons for fill up for me so roughly 3-4 bucks a tank. Not that big of a deal for a truck that runs smoother and with more power/responsiveness. I have considered CAI and anything that could give you about 30 hp/torque. This truck would be perfect under those power numbers. I have read into the CAI for the tundra and i think the tacoma is the same/ they put an air flow accelerator and trd filter... I have the filter already so I dont wanna pay 400 for a accelerator that cost the tundra guys 15 bucks sold separately.

 

So weird that this post came up. After quite a bit of research and the fact I now have it by my house I put in a full tank of E15 and I swear it drives smoother and seems to have more power. I'm at a little under 1/2 tank now but I'm going to keep using it and see how it does

 

There is an awful lot of speculation in this thread..... I'll play too.

More engine speed may or may not give more power in the Taco Engine Configuration. Doesn't matter for most of us as we don't drive our trucks around at 6000+ rpm.

Will the engine change tune due change in octane? Reasonable to expect a manufacturer to apply different maps or the ability to adjust for commonly available fuels.

30hp for changing to 91 octane? Maybe. I would think it would be possible if the engine was built for 91 and it gets down tuned for 87.

More realistically I'd think you would build a truck to run on 87 and have everything set up for that octane in order to improve CAFE numbers. If so, I don't think you could get 30hp improvement on just an octane change.

I would like to see more low rpm torque than than high rpm horsepower anyway. It's a truck.

 

I also had the TRD filter before the intake came out so I found the following web site that will sell the parts seperately. The entire TRD intake minus the filter will be 277 or you can buy just the accelerator for $23.64. Please be aware that you will not get 30 HP but probably closer to 2-4 HP. If you want 30 HP then you will need to look at the URD y pipe which will be close to that.
https://www.oempartworld.com/?p=catalog&mode=search&search_in=all&search_str=ptr03-35160

 

I have to agree ... went to the gas station the other night and they were out of 87 & 89 and I was on E ... so I filled up on 91 ... I noticed the difference in this tank very quickly, especially when getting on the highway ... not 30 HP but noticeable for sure.

 

WE NEED MORE POWAAAHHHH

 

The increase you guys are feeling is all in your head. Placebo