Tony1

iTrader: (1)

Ted, where does your information come from?

These EV14 injectors are rated to 8 bar by Bosch. That's not 8 bar on a sunny day in a drag car for 8 seconds. That's 8 bar in the real world for 200k miles in any condition.

BMW runs these on many of the new models at 90psi.

There really is no downside to running these at 100psi except that your fuel pump/pumps have to be up to par.

Ted B

iTrader: (6)

I was never referring to how much FP these injectors can take before they cease to function or rupture. My point was rhetorical - having the correct size injector is a better proposition than increasing the base FP to compensate for an incorrectly sized injector.

In the case of this injector, which is published as a '1000cc', but apparently flows more like 800cc injectors, there is no alternative except to raise FP. And if one elects to go that route, yes, reconfiguring the fuel system is absolutely a necessity.

less10

iTrader: (17)

What I was refering too with the base fuel pressure of these injectors is because of the atomization that a saturated injector creates. A saturated injector will make fuel way smaller in size than a peak and hold injector. The reason for the high fuel pressure is becaue these injectors will handle that pressure and the higher the pressure is for better atomization. What I mentioned has nothing to do with the extremely high power and "lack of injector" for 900whp you mention above. If I recall correctly he is running 8 of these injectors on his car.

Ted B

iTrader: (6)

?

I'm not doubting anything about these injectors specifically, but . . .

Please explain in detail how the electrical impedance of the actuating coil influences the atomization quality of the liquid itself.

Tony1

iTrader: (1)

It doesn't, he's mistaken.

Increased fuel pressure does however improve fuel atomization with no downside.

We made 701whp on an S2000 with 4 of these injectors and dual walbro pumps, un modified, which top out at 75psi. This is on an engine reving to 9k and running Q16 fuel, which is oxygenated. The car was running 27psi boost, so we couldn't have had the pressure turned way up. Don't act like these injectors won't support any power at 3 bar. They flow 880cc/min give or take on mineral spirits. If you start running your car on mineral spirits, then that number is relevant. If you run in on gas like the rest of us, then they flow 1000cc/min for your application.

Having the 'correct' injector size means having an injector that puts the right amount of fuel in the motor. You can get there with size or with pressure, or with both. Tell the F1 guys that they're doing it all wrong with fuel pressure, they should run a big POS injector that doesn't atomize fuel instead.

Ted B

iTrader: (6)

Increasing fuel pressure does not always improve atomization. It depends on the type of injector. In fact, I seem to recall that increasing FP only improves atomization with a single pintle type. IIRC, at least some Bosch injectors are/were SP, but I don't know about the new style, so I have no further comment.

I have my own idea as to how injectors should be rated, but if I want to compare the flow rates of two different injectors, it serves me better if they are rated via the same method, whatever it is. The same can be said for comparing two cars on the same brand of dyno, even if the dyno is considered to be less-than-optimum. Why? Because it's all relative.

I'm not in a position to tell the F1 guys anything. AFAIK, no one here is running normally aspirated engines that depend upon turning 19k rpm to make power, so again, no comment.

Again for probably the 10th time, I'm not saying anything specific to the injectors you are selling. I am accepting everything you say about them at face value. The cautions I make are specifically for the benefit of those who find this discussion via search, and get it in their mind they should just take their off-the-shelf dual in-tank fuel system and crank the base FP way up.

twkdcd595

Sorry this may come off rude but why do you continue to post up repeating the same rhetoric over and over then in light of your statement I highlighted. I know, I know... we get it, in an application with pumps and injectors not capable of operating or taking advantage of higher fuel pressure, it is a bad idea. Thing is it could have been said that simply for reference if someone was thinking you could do it with just any injectors instead of these Bosch units which are designed to operate at high pressures.

This is about the Bosch 1000cc saturated injectors. So now that you have taken 2 pages of back/ forth to explain you are not contibuting anything about these injectors specifically and reiterated your "cautions" about a half dozen times... can we get back to the topic?

Just to add on topic a bit more agian, I just bypassed my resistor box setup in my application (piece of cake) and ordered these injectors, 2nd 044 pump, Weldon regulator, etc. The more I read and see proof of these injectors performance being shared all over the forums with dyno sheets and rave reviews from highly respected tuners (including Tony), in various applications... I decided I wanted to make the switch from my p&h 1000's. Cant wait to see how they perform in comparison.

Tony1

iTrader: (1)

This is what started the conversation. It's just completely wrong in every aspect.

Why in the hell would you base your high performance engine around the fuel pressure that the manufacturer specified? The manufacturer specifies flow at 3 bar, everybody does. They also specify the max recommended operating pressure for those looking to either get more out of their injector or maximize fuel pressure.

There is not a high performance race car out there who doesn't understand the benefits of running higher fuel pressure. Some of the big power n/a guys are running over 120psi fuel pressure. Why? Because it makes more power and you can get more fuel out of a smaller injector which generally further improves atomization.

It's really very simple.

Ted B

iTrader: (6)

Injector manufacturers specify max pressure for the same reasons that tire makers do. Exceeding pressure limitations can physically damage the injector.

It should not be assumed that increasing FP improves atomization or otherwise alters the flow pattern. Many injectors do a good job of retaining their designed flow characteristics amidst pressure changes. They're designed that way.

Contrary to what one may assume, improving atomization is not always advantageous to a performance engine.


I'm not telling you these things because I made them up. Conduct more research and you will find that each of them is factual and correct.

Tony1

iTrader: (1)

I'm not making things up, we didn't flip a coin to decide if these atomize better at higher pressures, we've tested them.

Show me one situation where better fuel atomization is not advantageous and i'll show you 20 situations where it is. You obviously know more than I do and I love to learn new things, i'm all ears.

Also, have you heard of 'factor of safety'? Bosch isn't going to send out recommended pressures that are on edge of causing damage. These injectors test fine on the bench to over 120psi, but we limit the data at 100psi.

Seriously, does BMW using these things at 90psi on stock BMW's not say anything at all?

Ted B

iTrader: (6)

Tony, what type of injectors are these? All this chatter, and no one has revealed this important piece of information.

I don't know first hand about Bosch's max pressure rating or their safety buffer, so I won't make guesswork. They engineered the part, so I'll give them the benefit of the doubt.

I won't make assumptions about BMW's reasoning if they now use a 6 bar FP regulator. An acquaintance of mine is a BMW engineer in Germany, and I'm happy to ask him. As I indicated previously, assuming that better atomization has anything to do with it, that would be for two possible reasons (a) this particular type of injector increases atomization at higher pressure, and (b) increasing atomization is always helpful to fuel economy and emissions (a top priority), but isn't always helpful to power. There exists a point beyond which greater atomization is not better where this is concerned.


Well, the info I've stated isn't new, and it isn't a secret. I haven't recorded references for every time I've encountered it over the years, but I'm happy to take 5-10 min and see if I can find a credible source.

Ted B

iTrader: (6)

Here you go:

Injector Tech Notes

The atomization and pattern width will increase on single discharge pintle type injectors at, higher pressures. The Lucas Disc type does not deviate as severely. Dual discharge, diffuser type, pintle injectors don't change atomization quality at higher pressures, like the single pintle discharge injectors.

Indy car injectors are very precisely targeted and timed to provide a solid stream of fuel with non-existent atomization, LBDS, "Laser Beam Delivery System".

A wide, finely atomized pattern is wonderful for emissions and economy but can cause problems in higher performance engines. At low RPMs, with a low air flow rate, the slow moving finely atomized fuel has enough time to get past the valve and create a close to stoichiometric mixture. (Air/Fuel mixture of 14.70 - Chemically ideal) As RPMs increase this mass can't keep up, with valve open time, and many of the fuel droplets impinge the port wall and condense. Atomized fuel can only travel at port "air speed" and in large quantities it can actually displace air in the port. With a highly atomized mix in the port, at intake valve opening, the lighter droplets of fuel will be partly blown back up the port. This is caused by the residual exhaust pressure still resident in the combustion chamber.

It's a known fact that you can't burn fuel until it's atomized. It's also known that you can't burn fuel without air. The most important, of all known facts is that you can't burn anything, if it's not in the combustion chamber. The secret is to provide adequately atomized fuel with as much air as possible. ... What all this means is, different engine designs require a different type of injector to operate efficiently and that 100% atomization is not always required or desired.


These sections are supported by published SAE testing, so consider that FWIW. I hope this helps.

less10

iTrader: (17)

Thats good info. In the statement about high pressure and fuel atomization in high performance engines it says it can cause a problem...not that it will cause a problem.

Maybe you should tell tony to turn his FP down?

GST Motorsports

iTrader: (8)

I'll have to agree with you on this one. To that point, the new BlueMax run way way way way better.

Ted B

iTrader: (6)

That is correct. Increasing atomization beyond a certain point can cause issues at high power levels, but not every injector's atomization and flow pattern is significantly altered by increased FP.




If additional pressure is required to get sufficient flow rates, there's no other alternative except to use 2 injectors per cylinder.