Topic: HPFP or in tank pump... whats the real limiting fuel factor?

[SKY888]

Carbeurators and Throttle Body Injection work perfectly fine under this same principle, so I don't think anyone should be concerned.

Pls tell me how you can assure equal fuel distribution on each cylinder with the 5th injector kit.  If you can tell me how..........then I'll change my mind.   

but if you cant....then I'll stick with what I said.

[Critterman]

The fifth injector would have to fire a split second before each of the other injectors fired.  Could be done I guess.

[SKY888]

Huh? Ethanol energy from burning is LESS than the one from gas, that's why you have to pour 30% more when running on E85 to match the power obtained from gas. Has nothing to do with LNF in particular 

yes, Ethanol provides 30% less energy compared to regular fuel.    That's why we add 30% more volume when using E85.

But I'm not comparing E85 vs 93 octane.   I'm comparing E85 vs higher octane race gas.

The higher octane Race Gas fuels burn slower than 93 octane   


Ethanol burning "colder" means less energy so no gains from here 

E85 ends up running cooler cylinder temps then the 100 octane gas, which allows more timing, more boost and less detonation.   That's why you get your gains.


Q: how many of you will drive the car daily with over 450whp? (joshmass has a pretty good point imho)
You afford many thousands in engine mods and you don't want to spend 100$/race on race fuel?


Even FWD cobalts have been DDing their 450++ cars.   
A couple of them are 500whp right now.   And one guy is building a 700whp set-up, that he claims that he'll dd.

What more with our RWD kappas?     Once finished, I'll dd my car during summer (but no longer winter)

If I can save with Ethanol buying less than $4/gal......compared to a race gas $15/gal............and have similar whp/tq.....I will get Ethanol.

I dont like burning my money, you know?

I'll spend it on mods.....but not waste money on race gas

   

[SKY888]

550-600whp and boost at high rpms on our cars = un-streetable 100%

you don't have to WOT when driving on the streets, and be driving stupid and can kill somebody.

Drive like a normal person....and your 500whp car will be fine.

Right foot has the control 

[snaponbob]

Kenny, the BIGGEST problem with tuning for maximum power in ANY general distribution system (anything that is not a 1:1 TIMED fuel system (one carb per cylinder or one sequential injector per cylinder) is even distribution of fuel and air. A single injector or carb will have lean and rich mixes depending on the furthest or nearest cylinder to the fuel source. THIS is the advantage of individual timed fuel sources for each cylinder. A single 4 bbl on a V8 WILL have lean and rich cylinders. Same with a throttle body injection systems. And the higher the specific horsepower needs the greater the problem becomes. That is why direct injection is such a great advance in power and economy - VERY precise metering. Otherwise, we would have carbs on the LNF !!!!!!!!!!!!!!!!!!

[Sol Asylum]

Carbeurators and Throttle Body Injection work perfectly fine under this same principle, so I don't think anyone should be concerned.

Actually on a carbed engine with EGT probes on each cylinder's exhaust stack will show that some cylinders will be running rich and some lean.  So to be safe you adjust the mixture using the leanest running cylinder which can mean the others are running richer then ideal.

[SKY888]

Actually on a carbed engine with EGT probes on each cylinder's exhaust stack will show that some cylinders will be running rich and some lean.  So to be safe you adjust the mixture using the leanest running cylinder which can mean the others are running richer then ideal.

Kenny, the BIGGEST problem with tuning for maximum power in ANY general distribution system (anything that is not a 1:1 TIMED fuel system (one carb per cylinder or one sequential injector per cylinder) is even distribution of fuel and air. A single injector or carb will have lean and rich mixes depending on the furthest or nearest cylinder to the fuel source. THIS is the advantage of individual timed fuel sources for each cylinder. A single 4 bbl on a V8 WILL have lean and rich cylinders. Same with a throttle body injection systems. And the higher the specific horsepower needs the greater the problem becomes. That is why direct injection is such a great advance in power and economy - VERY precise metering. Otherwise, we would have carbs on the LNF !!!!!!!!!!!!!!!!!!

^^^^
these!

[kennysabarese]

The fifth injector would have to fire a split second before each of the other injectors fired.  Could be done I guess.

From my research the 5th injector is open all the time. Like nitrous.

[kennysabarese]

Kenny, the BIGGEST problem with tuning for maximum power in ANY general distribution system (anything that is not a 1:1 TIMED fuel system (one carb per cylinder or one sequential injector per cylinder) is even distribution of fuel and air. A single injector or carb will have lean and rich mixes depending on the furthest or nearest cylinder to the fuel source. THIS is the advantage of individual timed fuel sources for each cylinder. A single 4 bbl on a V8 WILL have lean and rich cylinders. Same with a throttle body injection systems. And the higher the specific horsepower needs the greater the problem becomes. That is why direct injection is such a great advance in power and economy - VERY precise metering. Otherwise, we would have carbs on the LNF !!!!!!!!!!!!!!!!!!

Yes, I am aware of the advantages of modern fuel injection and DI and no where did I state that these older technologies perform equally to today's systems. Multiple injectors is definitely better than one injector.

All I said was that a 5th injector doesn't mean your engine will blow up.

[SKY888]

Carbeurators and Throttle Body Injection work perfectly fine under this same principle, so I don't think anyone should be concerned.

thats what you mentioned.


Like what SOB mentioned, pushing the engine to its max .......a lil issue, becomes exponentially a big issue.   

If you run a 600whp LNF engine....using 5th injector kit....you have no way to equalize fuel distribution to each runner....to each cylinder. And you mentioned that anybody should not be concerned about it?
If I spent tons of money and research on a 600whp engine, I need to be concerned about it.   Yeah, it might not blow right away......but with more abuse, and push it even more........then you tell me, if its not a concern.

Adding manifold port injection on an LNF .....is different.  You'll be able to at least equalize fuel distribution on each cylinder.   

[kennysabarese]

I'm sorry that my first statement regarding this was not clear, that was my mistake.

Unequal fuel to all cylinders will result in less power because you have to run rich in order to be safe. It can be done safely. My references to carbs is just to let people know that this method of injection can be done safely, even if it's not the best way. More precise injection with multiple injectors is better, and I would go this route if I was doing it myself.

[SKY888]

theres actually a  big chaos at the other forum about that 5th injector kit.
that vendor is really pushing that the 5th injector kit is "safe" and can do the same thing as PI.

the knowldegeable tuners out there don't agree. James in particular.

According to the vendor.........it is affordable and can provide the benefits of PI.     And PI will be too costly.

I rather pay more, and do it right.    Than be cheap......and pay more in the long run.

A very knowldgeable LNF tuner that I know actually built the exact "5th injector kit".....that that vendor was selling....from the same size injector to controller.......to test it himself.

The injector being put in that hole has about a 1/16 of an inch or MAYBE 1/4 of an inch before it sprays directly onto a wall. The fuel will then turn back into liquid form and run down the passageway, to pour into the manifold on the side of the throttle body opening. Who here thinks that's a good idea?

Spraying an atomized mixture into a hole like this WILL turn it back into a liquid and it will pour out the passageway








but I guess it might still be "safe" since the speed of air flowing during high boost is soooo fast and strong that the fuel will probably be atomized anyways.

but my only concern still is the equal distribution to each cylinder......especially if you're relying on enough fuel during high power situation. And most importantly a good AFR.

[kennysabarese]

that vendor is really pushing that the 5th injector kit is "safe" and can do the same thing as PI.

This vendor is totally wrong. It cannot do the same things as PI.

According to the vendor.........it is affordable and can provide the benefits of PI.     And PI will be too costly.

It is more affordable. But it will not equal PI. What is affordable varies per person.

A very knowldgeable LNF tuner that I know actually built the exact "5th injector kit".....that that vendor was selling....from the same size injector to controller.......to test it himself.

The injector being put in that hole has about a 1/16 of an inch or MAYBE 1/4 of an inch before it sprays directly onto a wall. The fuel will then turn back into liquid form and run down the passageway, to pour into the manifold on the side of the throttle body opening. Who here thinks that's a good idea?

I don't think it's a good idea, I would not spray a 5th injector in that location. Maybe there is a better place.


Maybe the design of the LNF makes it impossible to do a 5th injector correctly. If that is the I case would certainly not recommend it to anyone on an LNF. And I would never recommend the kit you are referring to, because it seems to be poorly designed.

[SKY888]

it might work fine kenny....since 2-3 cars are running it. 

But I am not a fan at all.

I know that they did a PI set-up last year......and I was very interested to get one from them.....but didnt sell that kit to the public.   So I'm building my own PI system.    I'm guessing the cost will be too much for the cobalt crowd.     So they revised it down to a "5th injector kit"  so it is more affordable to the cobalt crowd.

[kennysabarese]

Yeah we'll see, if they can prove it's reliable that's great, but I wouldn't touch it if they are really spraying gas into a wall. That's just scary.

There's plenty of other cars that do this, or other methods of single point of injection successfully. Maybe it's just not right for the LNF.

[Gentleman Jack]

Push push push -> Envelope

bigger pump, bigger fuel lines, bigger injectors, bigger boom. 

It's only money.

Curious comment about the Cobalt crowd.

[miller11386]

Antonio, I agree with you 100%.

Especially due to the fact if you actually NEED  the 5th injector kit, you could probably benefit from an better intake mani anyway. And we are talking ~1k in the price of a build for a full PI setup, most of that being a manifold.

If I go PI, I will definitely be putting 4 injectors on the mani. Not one.

[kennysabarese]

*sigh*

[joshmass]

I'm almost sorry I brought up the 5th injector option 

We should keep in mind though that the vendor in question has a reputation for pushing things to their limits and blowing up motors in the process. Seeing that long term testing has never been done with the setup, it's anyone's guess as to what the limitations or implications are.

On the flipside, if you're just looking to make more power than stock and aren't pushing it to the limits, I don't see why it couldn't hurt. As long as you're monitoring your A/F and tuning safely it's not much different than adding a water/meth kit. The only difference is the injection point really.

Now that I think of it, I wonder if you could use a water/meth kit but spray E85 instead? Has anyone tried that?

[SKY888]

I'm almost sorry I brought up the 5th injector option 

We should keep in mind though that the vendor in question has a reputation for pushing things to their limits and blowing up motors in the process. Seeing that long term testing has never been done with the setup, it's anyone's guess as to what the limitations or implications are.

On the flipside, if you're just looking to make more power than stock and aren't pushing it to the limits, I don't see why it couldn't hurt. As long as you're monitoring your A/F and tuning safely it's not much different than adding a water/meth kit. The only difference is the injection point really.

Now that I think of it, I wonder if you could use a water/meth kit but spray E85 instead? Has anyone tried that?

just get a bigger nozzle Josh.    I believe your system is E85 compatible anyways.  Ask Jeff Howerton, to double check.

The w/m nozzles are not as accurate compared to an injector though.


if you do this....just make sure you watch your EGT on each tube of your exhaust manifold.

[joshmass]

just get a bigger nozzle Josh.    I believe your system is E85 compatible anyways.  Ask Jeff Howerton, to double check.

The w/m nozzles are not as accurate compared to an injector though.


if you do this....just make sure you watch your EGT on each tube of your exhaust manifold.

I believe the system is compatible but I would definitely check with Jeff first. I just need to upgrade the injector seals. I've got a single EGT already plumbed into the manifold. Seeing that the system sprays into the cold side pipe, it should have enough time to evenly mix with the air before hitting the intake I would think. That's how it's supposed to work with the water/meth at least. Then again, I'm no engineer....

[SKY888]

plus if you're spraying using a large nozzle....and injecting more E85.............I suggest installing the nozzle in a 45 degree angle (facing towards the direction of the TB)....to prevent "pooling"

another guy told me an interesting idea.  He said that injecting 45 degree the opposited direction (direction towards the IC)........to make sure your fuel be more atomized ........since the incoming pressurized air will help the situation.   I never tried that way though.....so I can't guarantee

[joshmass]

plus if you're spraying using a large nozzle....and injecting more E85.............I suggest installing the nozzle in a 45 degree angle (facing towards the direction of the TB)....to prevent "pooling"

another guy told me an interesting idea.  He said that injecting 45 degree the opposited direction (direction towards the IC)........to make sure your fuel be more atomized ........since the incoming pressurized air will help the situation.   I never tried that way though.....so I can't guarantee

To be honest, we just installed it the way Jeff told us to. He's got the degree

[SKY888]

if Fred followed directions........lol

[rlhammon]

Now that I think of it, I wonder if you could use a water/meth kit but spray E85 instead? Has anyone tried that?

I've been looking into this over the winter.  I can't find a reason that it wouldn't work, except that I'd need to spend some considerable time on a dyno w/ data logging to see what is going on to tune the w/m system with the E85.  I don't have that kind of resources (time and/or money).

Bob and I are limited in modifications we can make (nothing internal to the engine, stock turbo), which limits what we can do.  As to the questions about ultimate goals... maximize hp and tq in the most useable fashion possible, or in other words, be faster than the EVO's!  What is that number??  We don't know, because we haven't gotten there yet.

We have both run 100+ octane and E85, and mixtures... but fueling issues come into play with E* and the power isn't there with 100+ octane fuel (I've run about 20 gallons of 104 in testing).  I get more power on a E* mixture than going over 100 octane, and I can get E* at multiple locations 24 hours a day.  Without a doubt it's the best route for Bob and I; however I think we are limited to an E47 setup currently.