do you need to run premium gas with super charger or not?

wait what? I never heard this before?

its hot as hell here all the time but not dry, its always super humid instead.

are you saying people in states where it gets really hot shouldn't use SC?

 

The urd 7th not only gives you hp...but it also helps you boost safely...I run a 190 walbro pump and a urd 7th injector kit

 

Not at all, you've got humidity , your good

 

Installing forced induction, and running regular gasoline is like training for a marathon and shooting yourself in the foot.

 

this is like speaking Chinese to me, please explain what these things are and why you do them

are you saying the 7th injector is so it doesn't run lean?

and is the 190 walbro pump a brand of high pressure fuel pump?

also what does the urd pulley do? does it turn the fins faster for more pressure or slower for less pressure and presumably not running as lean

 

Urd 7th adds more fuel at low and high boost to prevent running lean...the fuel pump just pumps more fuel faster so it can keep up with the boost...the pulley spins faster therefore more boost

 

so if I follow you correctly, all of these things are designed for it to function safer for the engine to not run lean under any conditions and it also makes it work better and be more efficient, rather then being used just trying to squeeze out more power? so while you don't "have to have" any of that, you really should install all of that if you are going to install the SC.

does that about sum it up?

 

Exactly!

 

All of the URD stuff is meant so you can boost safely and not risk damaging your engine. There are 2 ways the TRD supercharger can harm your engine if you do not have any fueling upgrades.

1. High RPM lean out: Boosting at high RPMs requires more fuel than the stock fuel system can handle, which makes sense because the stock system was designed for a naturally aspirated engine.

2. High gear/low rpm ping (pre ignition): The ECU uses many inputs to decide how it should adjust the ignition timing. Higher intake temps and large engine loads will cause the ECU to retard to timing (ignite the air fuel mixture later) to avoiding maximum cylinder pressure before the piston reaches top dead center. Once again, this system was designed for a naturally aspirated engine. Stuff 6psi into the cylinder and the ECU can only do so much to retard the timing enough. Not to mention the air is actually heated as it is compressed through the S/C (and picks up heat from the S/C which gets extremely hot) which makes it more prone to pre ignition. Also, the ECU actually has no idea of the boost because the MAF monitors before the air is compressed in the S/C.

The URD 7th injector kit comes with the AIC (additional injector controller). This controller is a piggyback ECU that controls the additional injector as well as alters the stock ECU's ignition timing abilities. Its called a piggyback ECU because it taps into the stock ECU through a few of the wires in the ECU harness and alters their inputs.

1. To address the lean out issue, the kit includes a larger fuel pump (walbro 190) which helps flow more fuel as well as a 7th injector which helps add more fuel under boost at high RPMs. The amount of fuel added can be adjusted using the AIC. There are also some bonus features of the 7th injector which help add some hp. The 7th injector mounts on the supercharger itself and shoots the extra fuel into the SC. This helps seal the rotors to the SC housing which makes the SC more efficient as well as possibly put out a hair more boost. Also, the fuel being injected helps remove some of the heat I mentioned earlier that is picked up by the air (similar to what meth injection does).

2. The pre ignition issue can be fixed as well with the URD 7th injector kit. The AIC taps into the crank and camshaft sensor wires to alter the signal which will allow the ECU to retard the timing beyond its stock limits. The amount of timing that is being retarded can be adjusted as well using the software provided.

Adjusting when/how much fuel is injected by the 7th injector and when/how much timing is retarded is how you tune to have your engine run safely and perform to its maximum capability with the TRD supercharger.

Therefore in my eyes, these upgrades are something you "have to have".

The only thing that you don't "have to have" from URD is the pulley. This just spins the SC faster to create more boost/hp. But if you have the 7th injector kit, you may as well get the smaller pulley since you can tune for the extra boost.

To answer some of your other questions, larger injectors are not needed. The 7th injector paired with the stock injectors gets the job done. Larger primary injectors are also harder to tune.

I haven't noticed any real difference in MPG's from before and after the SC.

 

thanks, this is the most comprehensive real world info I have seen and with what you have said, I agree these "upgrades" are not something you can do without unless you want to gamble on damaging your engine so the comment that you can simply bolt on a SC and don't "need" to do anything else. while technically accurate, is not really true.

I now truly understand what is involved in adding a SC to the truck and while you didn't address this part, I would assume a less restrictive exhaust system just makes common sense to go along with a SC install so all that added flow into the engine has no trouble efficiently being able to leave the engine.

I see now why someone said a SC will cost you over $4k even though the SC only costs $3k

 

An engine is simply an air pump. The more air you can stuff in, the more fuel you can add, creating more power. You don't need huge exhausts on supercharged engines because the positive displacement blower does a good job of pushing exhaust gasses out. Too large of an exhaust can also slow down exhaust gas velocity, resulting in worse bottom end torque.

Like said above, super chargers create a lot of heat. One way to eliminate that is an intercooler. Another way is with nitrous. Doubt you want to really mess with either of those at this Point.

Heat in an engine can cause pre-ignition, or detonation. Essentially the fuel ignites before the spark plug actually is energized. This is the fastest way to destroy a gasoline internal combustion engine.

It's not a function of the fuel not burning fast enough, but of it flashing too early.

Higher octane fuels are refined with certain additives to resist detonation. A higher resistance to detonation allows you to advance the timing. Advanced timing allows you to safely ignite the gasoline/air mixture further ahead of TDC. This means the explosion occurs before the cylinder reaches max compression. This results in a more powerful engine.

If you run a supercharger, and use regular gasoline, you're defeating the purpose. You're opening yourself up to engine damage if the computer can't pull enough timing, and you're robbing yourself of petential power, defeating the goal of supercharging in the first place.

 

Your premium vs. regular cost formula will change. Your performance and efficiency with regular will stay about the same if you stay out of boost. But if you manage to get into boost at all, the performance will suffer badly. Stick with premium, just better all around for most reasons.

Your fuel mileage should improve. By adding forced induction, you're increasing the efficiency of your engine. It is able to make substantially more power without much more throttle input. Which means you accelerate more easily while using only a small amount more fuel. It's like trying to breathe through a straw, or with a fan blowing in front of your face. Takes less energy to accomplish a similar task.

I had a 2.0L 4cyl with a 1.3L supercharger on it. If I was in full boost, it literally got about 3mpg. If I stayed out of boost, and kept it at a constant speed, it would get close to 45mpg, vs, 38 max with the stock supercharger.

 

Sorry for the multiple posts, but I'm kinda adding details as I read back through and notice more things in the posts.

Again, engines are an air pump. Forced induction increases their efficiency. Boost in a boots blower setup is really just a measure of resistance.

As an example, a turbo or centrifugal supercharger compress air in the turbine itself. A roots blower just packs air in, like your suitcase when you're coming home from a vacation, and you can't figure out how it all fit in on the way there lol.

The boost gauge is simply measuring resistance to flow. My cobalt stock made 12lbs of boost. When I removed the factory cast exhaust manifold and installed a long tube header, that dropped to 10lbs. However, even with less boost, I was making approx 20 more hp.

Don't know if that helps at all, but just some general info. I would recommend getting a wide and o2 sensor and gauge.

 

thanks, just trying to wrap my head over the "whole package" that you truly need to run a SC vs the minimum you can get away with or just "make do" with using.

I don't believe in half measures or doing things "just good enough" so I prefer to do it the right way or don't do it at all. I think that's the only way things should be done and planned for doing.

if I get a SC I need to plan to purchase the entire equipt package and in my case I dont have the budget so unless I can buy a supercharged Tacoma, strip the SC and everything else and swap parts with mine then resell that other truck, I don't forsee ever having the money to do this, although it sounds like a very attractive mod.

 

I am the same way and did it right the first time around. I did months of research to become familiar with what I would need, how to install it, and how to tune it. It was work, but it was a fun learning process. In all honesty, the TRD supercharger is fun, but does not by any means make the truck fast. Especially if you have larger tires, armor, lift, etc...

 

Once the rest of my truck is done, I'll be grabbing the LCE kit for the 2.7. Will be nice to keep my mpg's and bump up to the power of the v6

 

You should be getting lower gas mileage on higher octane fuels. The octane rating is a measure of how much of an additive is in the normal fuel so you actually have less usable "fuel" per volume. A misconception about high octane is it makes your motor run better. The only function of octane is to resist pre-detonation. A forced induction engine is going to have higher cylinder compression and consequently a greater risk of pre-detonation so the answer to your original question is yes, 91 octane at the least is mandatory. I think the FSM calls for 87 with a completely stock engine. I'm not sure where the confusion comes from.

The URD 7th is packaged as a kit, all of the components are designed to work together. Any of those items added by themselves with not make a difference. I wouldn't say this kit is necessary but I would say it will make a large difference. The s/c alone runs at about 50% of it's potential. The URD kit brings it to about 90%. It will produce more power at a safer capacity.

Gas mileage from stock to s/c is around 1 less mpg (average), and from s/c to 7th another 1 less. Under normal driving conditions mind you, a s/c can easily devour your tank in under 100 miles.

If you're going to s/c you might as well dish an extra k for the 7th IMO.

 

Not to burst your bubble but power output and fuel consumption are proportional.

 

well that's why im going to replace my 265/70/16 tires at 10.4" wide and 30.6" tall with some 215/60/16 tires at 8.46" wide and 26.2" tall to drop the truck a full 2" and at the same time, im hoping and expect it will be like regearing it so it should give the truck better mpg without having to do anything else to it (change speedo gear of course) and im also hoping it will reduce the way the CC keeps downshifting so much. I think this would be the biggest cost per difference in mpg and performance that I can make on a very limited budget, plus these tires cost $85 each instead of $150 each I paid for the stock size.

im just wondering, since the SC plus everything else needed, it might be cheaper to just drop in a 4.0 engine instead of going with the SC, or is it too big and not just going to drop in and fit?

 

Smaller tires = worse mpg. I'm not sure what's involved with the motor swap but I'd guess around $15k in parts and labor.