Anyone ever installed bigger injectors? (2 Viewers)

[Gassiper]

So it doesn’t look like the supercharger is gonna play out. After talking to a guy that is pretty well known in the Tundra world for turbos and performance he’s kind of talked me away from it. As much fun as a turbo would be I’m not gonna get that crazy. He said one of the biggest bang for your buck modifications is changing to a bigger 12 hole injector. He explained it wasn’t that it’s throwing more fuel but it’s delivering it in a different way. Instead of a squirt of fuel it’s more of a mist so it ends up burning completely instead of partially. All that to say it seems to me like a pretty good way to spend a couple hundred bucks. He also does a kit that uses the factory intake manifold from an 05-07 Tundra, throttle body adapter and a few other supporting pieces that makes a HUGE difference. I’m gonna start with the injectors and see what kind of difference they’ll make but was just curious if anyone had ever put a bigger injector in or not. I’ve orders the DT headers and plan on doing a little exhaust work as well.

 

[chrisbruck]

I'd say you won't notice a difference at all unless your current ones are clogged or otherwise faulty. You only need larger injectors when you add more air, like with a turbo or SC.

I'm pretty sure the Toyota engineers who designed the engine are pretty smart and optimized the injectors already. I wouldn't waste the money.

 

[Gassiper]

Those were my initial thoughts as well. But after talking to a couple of Tundra guys that have done the injector upgrade they all said it was well worth it. They all said their trucks just seemed to just run better. Because the fuel was being burnt completely it made for better throttle response, didn't feel as sluggish off the line and made things just feel smoother. I asked at what mileage they had changed them and none of them had over 40,000 miles when they did the upgrade. He said also that he'd sold hundreds of sets of these injectors and hadn't had any come back because they didn't perform.

 

[AllLC]

Hmmm...
Any Dyno Results?
This sounds interesting. Keep us posted.

 

[gatormark91]

Snake oil. I would love to see a back-to-back dyno pull with just bigger injectors, without any change to the MAF, cams, intake, or the tune. I would be suprised if the graph budged from stock. The ECU will adjust fuel to meet the fuel map, and nothing more. If you get better atomization, the ECU will see more fuel in the AF ratio downstream at the O2 sensors and adjust. If anything, you might see a tiny, tiny gain in MPG. Not worth the $$.

 

[Gassiper]

I’m trying to find a dyno open to do a before and after. The company I’m dealing with is Dirty Deeds industries. The owners name is Keith Carty and said he was on Mud at one point. One of the most knowledgeable guys I’ve ever talked to for sure. But I’m gonna do my best to get some real numbers and see if it really will make a difference. I figure it’s worth a $300 gamble.

 

[Nick T]

We already have 4 hole injectors, going to a 12 hole might give you better atomization at lower rpms so throttle response will be better, i doubt you will notice much difference if your original injectors are working properly. It's not like we are going from a single hole to a 12 hole. In any case, There will be absolutely no increase in hp as the ecu will only provide 11:1 - 14.7:1 afr no matter the size of the injector. Going too big will actually decrease idle quality as the injector dwell time is not enough to properly flow the correct amount of fuel.
Why is a supercharger not going to play out? I have a 4.7 TRD supercharged ( first version with 9th injector ) Tundra with 260k miles, 230k of which supercharged. Runs fine, just don't try to boost it beyond the 6-7psi factory setting.

The BIGGEST BANG FOR THE BUCK mod is gears.

 

[Somebodyelse5]

What was the supercharger going to cost? Feasible to just do a diesel swap?

 

[phi1osopher]

Interested and following conversation

 

[Gassiper]

They’re on the way. Should be here by the end of the week. I’ll try and get them in before the weekend

 

[suprarx7nut]

Be sure to do exact before and after Dyno runs. I don't believe this one bit. As another said, shake oil.

If you want more power and are ok with some louder exhaust, do the dt headers and an aftermarket exhaust. There are proven, dyno-backed gains there.

 

[caslim]

Does it have to be a TRD charger? Any others that could work?

 

[Eicca]

I’ll be putting this theory to test on my Lexus. I’m installing the 05-06 2UZ plastic intake manifold and I have to use injectors from a 2002 Sequioa to make it work.

Although, my 1UZ has 203k on it so the injectors are probably in need of cleaning anyway, so it won’t be a fair comparison by any stretch...

 

[dirtydeeds]

Thanks for the mentions guys.

I highly recommend guys research converting from 4 hole to 12 hole injectors. It’s a huge difference in driveability!!

Doing just the injectors has little to no gains up top. It’s all about throttle response. Low end power. Tip in. And part throttle acceleration. None of which may he measured on a dyno.

Installing the composite 05-06 Tundra intake on my turbo truck caused me to need an extra 50hp worth of fuel (when the truck ran on gas). That’s where the power is!!

The injectors are still well worth it though. The driveability alone makes the truck feel like you’ve installed a tuner. And we all know how much a tuner cost

 

[Eicca]

Thanks for the mentions guys.

I highly recommend guys research converting from 4 hole to 12 hole injectors. It’s a huge difference in driveability!!

Doing just the injectors has little to no gains up top. It’s all about throttle response. Low end power. Tip in. And part throttle acceleration. None of which may he measured on a dyno.

Installing the composite 05-06 Tundra intake on my turbo truck caused me to need an extra 50hp worth of fuel (when the truck ran on gas). That’s where the power is!!

The injectors are still well worth it though. The driveability alone makes the truck feel like you’ve installed a tuner. And we all know how much a tuner cost

Did you install the Tundra intake on a non-VVTi model, and if so, did you remember to use a wire or something to tie the ACIS butterflies shut?

 

[sailor95]

Very interested in how this turns out

 

[dirtydeeds]

Did you install the Tundra intake on a non-VVTi model, and if so, did you remember to use a wire or something to tie the ACIS butterflies shut?

Actually what I did was bypass the factory vacuum switch and plumbed the diaphragm straight to its vacuum source.

I drove around with the intake on my passenger seat testing for an hour or so with vacuum reference hooked up.

What I discovered is that less than 4” of cacuum causes the butterflies to open causing short runner operation. And all the vacuum switch did was make em shorter sooner.

So I figured short runner under load was a given. Without the switch hooked up I’m in short runner mode pretty much anytime here is he need to accelerate. Long runner mode is purely just for light throttle cruising.

The intake makes a huge difference all the way around. The injectors make a difference on everything but top end.

 

[Eicca]

Actually what I did was bypass the factory vacuum switch and plumbed the diaphragm straight to its vacuum source.

I drove around with the intake on my passenger seat testing for an hour or so with vacuum reference hooked up.

What I discovered is that less than 4” of cacuum causes the butterflies to open causing short runner operation. And all the vacuum switch did was make em shorter sooner.

So I figured short runner under load was a given. Without the switch hooked up I’m in short runner mode pretty much anytime here is he need to accelerate. Long runner mode is purely just for light throttle cruising.

The intake makes a huge difference all the way around. The injectors make a difference on everything but top end.

You are well informed and set to go then. Nice work.

 

[suprarx7nut]

Thanks for the mentions guys.

I highly recommend guys research converting from 4 hole to 12 hole injectors. It’s a huge difference in driveability!!

Doing just the injectors has little to no gains up top. It’s all about throttle response. Low end power. Tip in. And part throttle acceleration. None of which may he measured on a dyno.

Installing the composite 05-06 Tundra intake on my turbo truck caused me to need an extra 50hp worth of fuel (when the truck ran on gas). That’s where the power is!!

The injectors are still well worth it though. The driveability alone makes the truck feel like you’ve installed a tuner. And we all know how much a tuner cost

Low end power difference would still show up on a dyno, though. Part throttle acceleration can still be mapped if you log throttle percent during the run and go up and down the rev range a few times under partial throttle. If 30% throttle before and after shows a difference, I'll bite and call it an upgrade. I suspect that wouldn't be the case though. You can also map "tip in" by plotting the profiles of power if you apply throttle suddenly mid-run. You'd just need a shop willing to export some raw data.

Dyno charts are commonly just full throttle pulls, but they don't need to be.

You could lighten the throttle body cable or tweak the profile to be eccentric to make the motor "seem" more lively, but it's all a false sensation.

Call me a cynic, but I need dyno data to grasp the claimed benefit here. If it causes benefits you can't see on a dyno I have a real hard time believing you're not feeling the placebo effect.

 

[Eicca]

If nothing else, it’s way easier to lift that plastic manifold off when doing a starter...