New injector review - 72lpm 5 hole VCO 155 angle

[RCCUMMINS89]

Put in new injectors




Stay tuned.

[ellis93]

Nice title

What size injectors

[RCCUMMINS89]

Ok these are 72lpm fllow honed 5 hole injectors (think flowed honed 370s, but they are different.)

155 Spray angle injectors.

No haze when warmed up, so they are a burn cleaning injector. Need to adjust my timing as they both dropped my rpm about 200 rpms at idle as well as my truck now sounds like a prius. Even at 20 (estimated) degrees of timing.

When I get on it with my wastegate off (remember it's on a toggle) it opens at 20 psi..... my old injectors would produce 30psi and well it was hot. With new injectors it only produces 26 psi and well, it's hotter.

When I turn my wastegate on (opens at 40) my old injectors would produce 45 psi and about 1400 degrees (on a day like today) these numbers are as the truck was tuned right now. With new injectors it pegs 1600 degrees in less than 2 seconds and produces 52 pounds of boost. But truck is slower.


This is why: simply too much fuel for the air coming in. Perfect example of why too big of an injector will produce less power. Too many people go way too big thinking more fuel equals more power..... guarantee my truck would dyno 75hp less EASY and probably more.

Reason I went with these before the compounds is to prove this point and also to show how more boost and hotter egts does not equal more power.

[4thesporty]

remind me, is your engine a 92 also?

or rather do you run ic or non ic pistons?

[RCCUMMINS89]

92 with i/c pistons

[turboram]

You sir need more timing, then watch the egts and boost go down and the hp go up.
The problem is your fuel is burning in the exhaust and not in the cylinders

[turboram]

I thought your vehicle was somewhat heavy and than means you need bigger injectors for more power

[RCCUMMINS89]

LOL.... this proves what I said in the other thread.

If what I was saying wasn't true, then I wouldn't of made more power with smaller injectors. Change this truck over to 3.07s and it would be faster. Hook my truck up to a sled and it would do better with these than my old injectors. (if my motor didn't melt).

But keep in mind that in "most" people's book these are tiny injectors

[RCCUMMINS89]

Let me show some examples.

my truck used to have traction issues in 2nd (obviously) and would bark the tires at 30-35mph when laying the hammer down in 3rd (keep in mind that RC's have a lot of rear end weight and large tires). My truck didn't have the power in 5th really up over 90mph.

Now my truck is slower in 2nd and 3rd, 4th is better, and 5th is my most powerful gear.

That is because the fuel is a slower burn and not a faster more explosive type of burn. This is why I was talking about in the other thread Nick. Also, we were talking about a 3000# car vs. our trucks.

I just sat here and typed out an explanation like 5 times and realized that it's pointless. I give up. I'm no longer going to try and explain how the dynamics of an explosion work because I'm simply going to go insane. I apparently am not a school teacher for a reason

[RCCUMMINS89]

I thought your vehicle was somewhat heavy and than means you need bigger injectors for more power

You've got me all flustered......

Where did I say that??? That's just the opposite of what I've ever said.

[oldestof11]

You went to a higher octane fuel rating. I get ya.

I wonder what would happen with higher pop pressures...

[RCCUMMINS89]

Jon.... yes that is a good way of putting it.

I chose to have them popped at 260 bar. Reason being, is we checked them at stock and kept going up to get the "best" looking spray. I chose this.

I just need more air..... yes obviously timing and tuning. But, I knew that going into this...... I wouldn't of gotten these sticks if I didn't ahve the low pressure turbo in the "stock" room

[turboram]

viewtopic.php?f=4&t=14325
Second post....

[RCCUMMINS89]

But when comparing our trucks to a car then yes, we require a different fueling. Doesn't say anything about my truck needing more fuel or larger injectors..... .

Let's put it this way.... would you set up your fueling the same for sled pulling as you would for drag racing... I sure wouldn't

[oldestof11]

Well Eric, i will disagree with you on the sled pull vs drag strip. Fact is most of the top racers use sled pulling tech to build their engines. In fact, Scheids and Hypermax's rails are both old sled pulling engines.