Flame Thrower

i have been researching injectors for the 5VZ engine and i am getting mixed signals and some numbers that just don't add up.

i know that the supercharged engines need larger injectors, i am already working on that. but will the stock engine get into a lean condition at peak power/high rpm on the stock injectors?

thanks

FT

vital22re

iTrader: (2)

They are just enough when running NA. However, just throwing larger injectors into these will not fix anything as you need to have a way as to control them. At idle they flow too much and generally more than "OE" so the ecu will forever be fighting them to lean them out.

Flame Thrower

ok. thanks.

Texas_Ace

DON'T install larger injectors. Just more hassle then it is worth unless you take the time to get something like an AEM FIC working.

The much better option is a 7th injector kit.

dsmjrv

even better than that and cheaper too is to just go meth/water injection

Texas_Ace

Well, meth injection. Water injection won't help the lean out issue, it will just stop the engine from melting.

Meth injection works GREAT but you need to know what you are doing and have access to 100% methanol in bulk to do it.

vasinvictor

iTrader: (3)

^ Meth works great- 24gph and I need more.

Texas_Ace

Yep, I was running 14gph and needed more with the supercharger. Not surprised at all that you need more with a turbo.

If your AFR's are in the high 11's with that much meth then you can rest pretty secure that you are making a fair amount over 300whp.

Jomoka

Preface this with some disclaimers: this hack is from the Volvo world, where it can work well on mildly boosted '+t' setups using stock injection systems, but I didn't do this on my car, I just went to a standalone replacement (Megasquirt, an MS1 box back in 2006, then an upgrade to MS3X a couple of years ago).

But a decent hack, if properly done, is to alter the MAF/AMM sensor in conjunction with increasing the size of the injectors. The MAF reads a percentage of the air that goes through the whole sensor tube, the small amount going through the sensor area is then interpolated back to assume a stock sized MAF housing. If you find or fabricate a larger diameter tube for the MAF sensor to sit in, this will retain the same/similar air flow readings at the sensor, all while MORE air goes into the engine.

Then you do some maths and determine how much more air is going through the larger MAF body, and you upsize the injectors by the same percentage. The stock ECU is still largely in the dark, it doesn't know the MAF is letting in more air at a given reading, and it doesn't know the injectors are sending in more fuel at a given opening time. But if you get the increased ratios fairly close, it will still use the O2 sensor readings to steer it into a nice clean tight stochio mixture.

That still leaves the issue of ignition retard under boost, but you're not really talking high boost with a supercharger anyhow.

Flame Thrower

i'm bringing some 254cc injectors to market. 1.6% more flow than stock injectors with an improved spray pattern.

it should be fun.

Texas_Ace

The issue with doing this is among other things that when you trick the ECU into running a lower duty it will also run more timing, making it even more knock prone.

Also this effects the whole tune for the engine, so everything it does will have to be adjusted and this is where people run into lots of quirks in daily driving, bad gas mileage ect.

The only way to properly use larger injectors is with some kind of ECU that takes full control over them, be it a standalone or a piggyback like the FIC. Otherwise you are asking for problems.

The spray pattern is nice but honestly see above, if the injectors are larger then stock you just run into issues. If it is such a small increase that it doesn't effect things (such as 1.6% larger) then it is also not going to help the lean out issue enough to matter.

Flame Thrower

i cannot fix the problem toyota created with poor ECU mapping. nobody can.

i asked a question for clarification because i was getting conflicting information. i was 98% sure, but i don't like that 2%.

toyota has always made world-class engines, but they used to use the cheapest fuel injectors that they can get away with. but i don't mind. as far as i can tell, i have sold nearly a thousand sets of upgrade injectors for toyota trucks.

i understand what you are saying, but you seem to believe that you know more about this than i do. just curious, do you have any data or research of your own? because it sure sounds like you are just repeating what others have to say.

Texas_Ace

Plenty of personal experience on various cars. Everytime I tried larger injectors without some form of proper management it was more hassle then it was worth.

But then I build my cars right, I don't accept a 5mpg drop that doesn't have to be there. I also don't tolerate anything but a safe tune on my cars.

Better fuel injectors are great, but the issue is that you spend all that money to end up with what tangible benefit on a stock engine?

Sure it might give a slight bump in MPG but that will take years to offset the cost. It might make a tad more power but is 1-2hp worth the cost?

You are welcome to sell the injectors, not saying they are bad, just saying I don't see the point. They have no benefits when cost is taken into account from my point of view.

Flame Thrower

ok. so the answer to my question is, no. no research. no, no actual data. you have little to offer but 'but then i build my cars right' and 'they have no benefits when cost is taken into account'.

i can accept your anecdotal evidence as factual. i do believe you had problems with other cars and other injectors. you made some poor choices, it happens.

but now you are once again making assertions with no data other than anecdotal evidence based on 'Everytime I tried larger injectors'. your decisions do not factor into my decisions, and you should leave them out of it.

i'm not going to be selling larger injectors. you said i was. why? i'm staying within the parameters of the statistical variance that denso allows within its own products, and that toyota was willing to accept when they did the original fuel mapping.

i'm not offering anything other than a slight improvement in performance in the low-rpm range (where it is most needed) and a slight improvement in mileage in the same range (where you spend almost all of your time). and if i can come in at the right price point, i should be able to sell a few sets.

Texas_Ace

Talk about the pot calling the kettle black.

Yes, I have seen hard data and research to support what I said but I am not going to waste my time to go find it. Exactly what point is in debate anyways?

You have not provided even a remote theory on why these injectors would be an upgrade considering the cost.

I on the other hand have laid out a well thought out and logic based argument on why they are a waste of money.

Fact, a slightly improved spray pattern at the very best, on a good day is good for a ~1mpg increase in MPG with our trucks (although most liekly far less).

Fact, At best a better spray pattern is good for a 1-2hp increase in power on our trucks, heck they fire in batch mode on the stock ECU IIRC, so spray pattern is going to have virtually zero effect on anything for that matter.

So do tell, what is the benefit of them consider you will not reap a cost savings from them for a VERY VERY long time and the cost per HP is outrages?

Provide actual logic for your point of view, not just "your wrong, I am right, I can't think of anything better to support my argument" please.

EDIT: Your a vendor here and I should just keep my mouth shut past this. I like supporting vendors of sites which is why I have been as nice as I have up to now. Plus I do think that injector upgrades have their place but only with the proper supporting mods.

Flame Thrower

wow. OK. where to start... let's try

"Fact, At best a better spray pattern is good for a 1-2hp increase in power on our trucks"

"Fact, a slightly improved spray pattern at the very best, on a good day is good for a ~1mpg increase in MPG with our trucks "

"you will not reap a cost savings from them for a VERY VERY long time and the cost per HP is outrages?"

so, since you don't know how much they are going to cost, nor do you know what the performance will be, what do you base your assertions on?

nothing? i (and the folks who have PMed me) are pretty sure its nothing.

my level of education generally keeps me from making baseless accusations. especially against somebody with more experience who has the ability to generate their own data when i do not.

http://science.howstuffworks.com/inn...ic-method6.htm

rworegon

TA and FT, keep it civil guys...........you both are stepping into the personal attack zone.

Texas_Ace

You still have yet to give a SINGLE counter argument of ANY kind.

Or even have an argument of your own.

AKA, you can't find fault with what I am saying.

Far as price, unless they are $50 (Which I am darn sure they won't be), you are not getting a worthwhile bang for your buck IMO.

You still have yet to give a single benefit that you should get from better injectors.

Either form a counter argument (or really an argument of any kind) or stop wasting my time. I can't stand internet people that follow the "can't argue with their logic, lets make it personal" form of debating.

Flame Thrower

ok. i don't have to have an argument. i have the science of combustion physics.

speaking of science, why don't you start researching the physics of gasoline combustion? it's amazing stuff. if you were to spend even an hour doing that, you would know 100x more than you know now.

then start working with the current generation of fuel injectors. i work with them on occasion. if you were to see what the state of the art in non DI (direct injection) injectors were, how modern spray patterns work, and what there is to be gained, i am confident that even you could see what you would want to move towards in the injection system in your own vehicle. what works for one will work for all (mostly). that's the beauty of science.

i could go down the rabbit hole talking about things like the bernoulli effect, evaporation and burn rates for various types of oxygenated and non-oxygenated fuels, the actual components in what is called 'gasoline', flame front propagation, peak thermal efficiency, stratified charge burn rates, and pressure rates vs piston movement.

but why bother with that? you just want to cause problems and say that i'm a crook.

Jomoka

It's not so much a trick as it is a rescaling. Keeping a boosted engines air and fuel volumes in ranges the stock ECU understands and expects.

But yeah, it's a hack, I never bothered with it. Even though Volvo has turbo versions of everything floating around in junkyards all over, even that only works as long as you stay close to stock boost levels. I went straight to yanking the Bosch computers out and installing the MS when I started tweaking it.