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Fuel injector spray

2.7K views 14 replies 5 participants last post by  NeedForSwede  
#1 ·
Gentlemen,

Been looking at fuel injectors, and their differences.

Am I right in thinking that seimen deka 630's deliver a "pencil" spray (straight).
And Bosch "green giants" deliver an "cone" spray. (wide)

Do I have any idea what I'm talking about?

Cheers
 
#3 ·
Didn't know if you knew this, but you MUST index the Dekkas. Meaning, line up the banks of "holes" with where intake ports are in each cylinder. Otherwise starting and transition maps are going to be a bitch to get *right*
-Cm
 
#4 ·
I've had deka's sitting here in my garage for a while, Waiting.

The tune I'm getting is set up perfectly(air,fuel) for green giants.

I could have run with the deka's but the mix would not be perfect. Had I lived a bit closer to the tuner(in the same country even :))he could have worked it out and made adjustments.
.I could data log stuff but...... I got other shit to do.


I got green giants for 200 bucks, delivered. I thought that was alright


P.s anyboby need some 630 deka's
 
#9 ·
Thanks anyway Cm,
I've already bought all this stuff, So I'm going to give the green giants a go.

I'll let you per-fect your tune for 12 months, I'll keep my dekka's just in case.

An injector made by a company like "bosch" can't be that bad,(can it)?.
I looked around on the web last night, Trying to dig up some dirt on green giants and from what I could find these green giants seem to be a popular injector.
These injectors are oem on volvo turbo's.
Maybe I was looking in the wrong places, but I could only find good info about these injectors.

I'm not saying that you guy's are wrong either.
 
#10 ·
You can say all this and that about the design and this one is better and this one should run this way or that way, but I have tuned a ton of cars with the green giants and they run awesome, no bad running issues as suggested, they run so well, you would not even know it has different injectors in the car, you definetely cannot say that about the 60# injectors. They work ok, but the warm up stuff is not perfect and I have retuned cars from all the major tuners and some work better than others, but they all some issues with cold start and warm up.

The green giants work very well for the 19T or T28 application and I will continue to stick with it, in my experience, they run just about like the stock ones and get better mileage than the 60# and have enough fuel for the 19T turbos. You want to go E85 or Gt30, then its time for the 60# and they do just fine for that set-up, but not really needed for the stg 5 tune in my opinion,

John
 
#12 ·
Can't vouch for that. You also have vastly more experience and in that capacity I bow out. However, while my car still does not run right with lambda enabled (can't seem to get help on that one:icon_frown: ) it drives exactly like a stock car when lambda is off in firmware-seriously. This I ascribe in part to the indexing of the injectors, which is a known issue with the Dekka's. Running purely in open loop I am now getting better MPG than I did before and the car behaves stock in every capacity. The only concession is that when cold it doesn't catch instantly, but then again, it never did.
JZW, you are actually one of the few who espouse the greens. Most here and elsewhere complain...YMMV
-Cm
 
#11 ·
Phew, That makes me feel better. ^

Look, I know nothing,
But I can't see how a company like "Bosch" would make a shitty fuel injector.

I'm looking forward to getting these in
I'm sure these things are going to run sweet.

Time will tell
 
#13 ·
Ok I have never found an answer to this question: How do tuned Saabs run near 100% duty cycles on the injectors and still run well? I mean I've only used online calculators, but I feel like for the first step upgrade, you would need at least a 550cc injector (i know the green giants flow at a lower rate). Turbo honda's start off at 450cc for a basic turbo application...Different cars, but duty cycles are duty cycles.
 
#14 · (Edited)
There's a big difference in how idc's are calculated across logging programs. For instance, evoscan is known to be 10-15% higher reading than actual idc due to the way it calculates off ipw. Either way I like to keep setups below 85ish%

Also comes down to injector type, impedance, and inner workings such as spring/tip/plunger that will determine recovery time after each pulse and how well they can maintain a useable spray pattern