How will 120 horse injectors compare to my box?

[RT66DOC]

OK you guys - I'm not as dumb as I look.

 

[truckstom]

Originally posted by CORed

Question... if you just get bigger injectors... no box, you will get increased power, but your EGT's will be higher since the boost will still stop at the stock 20 +/- lbs, right?????



Also, another related question. If a guy gets the injectors and a boost fooler w/ elbow, would it make HP and Torque numbers higher than with the injectors alone?

When I went from stock to DD2's, I didn't notice any real increase in EGT's... . this is unloaded toolin' around town... this is with a non-wastegated turbo also...



a related answer... HP may be a little higher, but I wouldn't think by much... a rule of thumb some guys go by is, 10 hp for each 1 pound of boost... just an estimation of course...

 

[Hohn]

The 10hp/psi of boost is NOT even CLOSE to being a good approximation.



If you port your head, you'll see LESS boost, but lower EGT.



Also, altitude screws with it too. NOtice that the new 04. 5 engines make 320 hp but don't have any more boost than past years (20-21psi)?



I also dynoed 382rwhp with only 30psi of boost.



There's just too many variables for the 10psi rule of thumb to work.



It was closer to accurate with the old 6bt5. 9 engines.



Justin

 

[CORed]

So... still not sure if there is a clear answer here or not?? I appreciate your personal experience truckstom... maybe someone can tell me... will injectors alone, on a stock engine (no computer mods) provide the advertised HP / Torque numbers?? Would it do so, but also increase EGTs - maybe just when towing??



And secondly, what benefit would adding a boost fooler w/ elbow provide? Would it possibly lower EGT's AND allow the injectors to reach their full potential??



Steve

 

[Bob Wagner]

adding injectors only will gain you the advertised hp gain and it will do it better than an electronic box.



Yes adding fuel does increase Egts



EDM's smoke less than extrude hone injectors hp to hp



Add a 60 - 80 hp injector and you will be happy





Yes, I boost fooler will let you exceed stock boost levels and lower egts.

 

[Hohn]

Originally posted by Bob Wagner

adding injectors only will gain you the advertised hp gain and it will do it better than an electronic box.



Yes adding fuel does increase Egts



EDM's smoke less than extrude hone injectors hp to hp



Add a 60 - 80 hp injector and you will be happy





Yes, I boost fooler will let you exceed stock boost levels and lower egts.

Adding larger injectors with NO OTHER electronics will only increase power to the extent you have the air to burn it. That's why you need a boost fooler or other box to increase boost. It's also why you don't need a boost fooler with very mild injectors like the RV275s.



Adding fuel does increase EGT-- unless a proportionate amount of air is added. This means either more boost, less intake restriction (cam, ported head, etc) or both.



I am not certain one can make the statement that injectors or a box is "better" in all cases. When you increase fueling rate, you change not only the QUANTITY of fuel delivered, but also the QUALITY of fuel delivery!!! This has HUGE implications. WHEN the fuel is delivered and how much is delivered changes the the level of strain on the engine.



If you don't load the engine a lot (tow heavy), then you can certainly get away with a shorter, higher quantity fuel injection event. This tends to produce a lot of torque but also creates a large spike in peak cylinder pressure.



A fueling box will spread out the fueling discharge. This lengthens the injection event but also tends to increase EGT since the fuel has less time to completely burn (time from injection end to opening of exhaust valve is less).



So you can see that there are two components of over fueling: injector rate-of-dicharge (flow rate) and solenoid duty cycle.



For you math guys, think of this formula:

FUELING= duty cycle*injector flow rate



Obviously, the more you have of one, the less of the other it takes to reach an overall fueling level.



So how do you determine how to set up your fueling??



Start with the duty cycle you are comfortable with. Is 65% fine with you? Then run the killer TST wide open. If you're only comfortable with 40%, then maybe you should buy a COMP, and NEVER turn it up over 3x5.



Once you've determined you max duty cycle, determine how big an injector you need for your fueling needs. If you want the power of a TST competition box, but can't tolerate the duty cycle, you're going to need a step or two bigger injectors.



Again, it's all in the balance between duty cycle and injector flow.





If I towed, I would tend to favor duty cycle (both on ETH and ETC engines) in the balance. With adequate fuel supply, the VP can handle it and be reliable. This give you more adjustability and EGT control (assuming wire tap box). It will also be easier on the engine at high loads (less peak cylinder pressure).



With no or light towing, then you can favor the injectors.



BTW-- The ETH engines run a higher duty cycle out of the box than the ETC engines do. That's why they make more power in stock form, even though they have SMALLER injectors. It also explains why the ETH engines respond so well to larger injectors as well as why they ETH engines don't get as much power from a wire-tap box. Since they're already using more duty cycle, the ETH engines leave the fueling boxes with less to play with (less headroom).



Hope this makes sense. Any questions, feel free to post or PM (PM is preferred).



Justin

 

[PRout]

Well said.

 

[CORed]

Wow... Hohn... and Bob... I very much appreciate your feedback and information. I feel truly educated even after being a TDR member for over a year. This question has been formulating in my head for quite sometime as I learned more and more.



Thanks, Hohn, for taking the time to give me the details. And Bob, I have definitely heard and read about the benefits of the EDM injectors and they are high on my list of desireables.



I will take what all has been said here and determine my approximate duty cycle... (probably relatively conservative) and keep saving my pennies.



What I am thinking at this point is EDM 1. 5 (ish) and stop there for the time being. (Maybe HOPEFULLY, during another group buy sometime down the road. ) Need time to save up for a clutch and don't need to rush a hit to my wallet. If I added a boost fooler, I should be able to keep my EGT's manageable for the type of driving I do and not spend too much.



Again, thanks all.

 

[jrandol]

Originally posted by CORed

Wow... Hohn... and Bob... I very much appreciate your feedback and information. I feel truly educated even after being a TDR member for over a year. This question has been formulating in my head for quite sometime as I learned more and more.



Thanks, Hohn, for taking the time to give me the details. And Bob, I have definitely heard and read about the benefits of the EDM injectors and they are high on my list of desireables.



I will take what all has been said here and determine my approximate duty cycle... (probably relatively conservative) and keep saving my pennies.



What I am thinking at this point is EDM 1. 5 (ish) and stop there for the time being. (Maybe HOPEFULLY, during another group buy sometime down the road. ) Need time to save up for a clutch and don't need to rush a hit to my wallet. If I added a boost fooler, I should be able to keep my EGT's manageable for the type of driving I do and not spend too much.



Again, thanks all.

You might think about just waiting and doing it right the 1st time, from experience I can tell you it costs a lot more in the long run taking steps up in HP than it would be just to set your rig up for the HP level you want to end at. My wallet wishes I would have!!

 

[Hohn]

Agreed. Knowing what I know NOW, I would have done this differently:



I would have bought the TST comp box right off the bat. Now I'm stuck with an EZ and would lose money upgrading.



I would have gone EDM instead of honed with injectors. Even a small EDM would be good. A 60hp Mach1 EDM *feels* like my 75hp DD2s. They throttle response is awesome and the smoke is almost nil. NOt to mention that the mach 1s are a mere $500. I paid more for my DD2s!



Justin

 

[Mad Bomber]

Originally posted by Hohn

I would have gone EDM instead of honed with injectors. Even a small EDM would be good. A 60hp Mach1 EDM *feels* like my 75hp DD2s. They throttle response is awesome and the smoke is almost nil. NOt to mention that the mach 1s are a mere $500. I paid more for my DD2s!



Justin

I agree EDM's are the way to go

 

[csevers]

Building it "right" the first time is a great slogan but when people upgrade they don't know how much the difference is going to be, it is hard to shoot for the moon, when you don't know what the moon feels like so to speak. I have taken "baby" steps in my quest for power. I have spent some money but like the steps I have taken. 120 ish hp injectors are nice and I can easily drive/tow on the injectors and a bigger turbo alone and not need the box, except if I need some insanity. I also was worried about not being able to "turn" off the injectors in bad weather but it has not been a problem, althou the throttle is very sensitive it is still very streetable.

It depends on how much smoke you want to or not to make while driving/towing. I would vote for useable power on injectors and play power on a wire tap box. This is just what I like with my truck.



Craig