Flow Force Question
 

I put in my FF injectors.

Are these, or not, the bow-tie spray pattern? If so, how do I keep them aligned properly? Mine seem quite free to rotate. I did use the extra spacers.

@nigelt

DNM

Interesting, I didn't think orientation mattered on these. Curious to find out if it does.

I oriented mine so the plug is facing up. I read something back then, when I did it, that made me come to that decision, but forgot what that was. I know you can run the OEM part number and get the data on the spray pattern.

This is interesting. Would this apply to all EV14 injectors such as the ID1000's

No. The GT500 injectors happen to be dual spray pattern. These were what FF used to use, not sure it is still the case. These need to be oriented with the plug facing upwards to be in the"correct" position in a Miata AFAIK. Not all EV14s are dual spray pattern though; and even those they are, the "clocking" of the pattern wrt. the plug may differ. I remember posting some info here https://www.miataturbo.net/engine-pe...ny-good-94531/

Wow. I've been running these injectors for quite some time, and this was never on my radar. I just have them clocked whichever way the harness wanted to seat. This is the old thread I found discussing the topic:

https://www.miataturbo.net/engine-pe...-75499/page10/

I wonder if Miater has any more insight.

i just stuck mine in the way the wires wanted to fit. no issues yet.

Ive fitted heaps now, jam em in and go pass emissions.

Easy.

Dann

What is the P/N? Do you have any not installed that you can check?

http://www.usrallyteam.com/content/products/injector/Bosch_Injector_data.xls

USRT put this together from the bosch pdf, that I cant easily locate atm. This is easier to use anyhow.

Waiting for Nigel, or until I pull my injectors back out and get P/N.

As Pointed out here FF were at least originally touted as utilizing the bowtie pattern to inject right at each valve.

Is that real important? IDK. Should we ignore that feature if it is available? I Think Not. Could combustion change if the injector rotated after tuning? Likely. Could it be enough to matter? IDK.

Seems to me that if these are bowtie, then they should be properly oriented. Otherwise, they should be conical spray pattern.

Hey guys, sorry for the slow uptake on catching this thread.

FF640 injectors have a dual cone spray pattern with a 15 degree offset. When the plugs are facing straight up, they perfectly fire a squirt into each valve hole. If it's possible to do so, you can try orienting it that way for OCD satisfaction, however that won't be possible on some cars such as NAs with stock intake manifolds AFAIK. There is tons of heat and turbulent air on the intake and compression strokes and the 6 hole disc creates excellent atomization. Even if you were somehow able to get the entire pulse squirting into one valve hole you will still get a homogenous mixture by the time the spark fires.

As noted, this doesn't apply to IDs which have a single stream gush. I would argue (with a nod to my extreme bias) that the atomization is more important than the direction since it will result in the gas becoming vapor faster. As a vapor it won't hit the cylinder walls and will more quickly become a homogenous mixture.

Nigel, That is 15* Alpha and 0* Gamma, correct? If so, then either straight up or straight down would be ideal.

OR, is that 15* Gamma, in which case only straight up is ideal?

While I'm being aanal, I may as well go all the way.

For Reference

Here's a nice visual. I'm not sure what you'd call that, but connectors up would give you the most direct spray into the intake ports.

Bosch part number is 0280158298

The googles say:
spray angle (alpha) 15*- 85*
Bent angle (gamma) 0*- 15*
http://www.bosch-motorsport.com/media/catalog_resources/Injection_Valve_EV_14_Datasheet_51_en_2775993867pd f.pdf

I can't find any more useful info than this. May be up to eyeballing the above video to estimate gamma.

Best I could do eyeballing that video with a plastic protractor. ~12.5* gamma.
https://cimg5.ibsrv.net/gimg/www.mia...b8113c3e35.png

Yep. Now we all have the answer to the original question. EDIT: We answered part of it. Ideally they should be oriented a certain way, but we don't know yet how best to keep them that way. The originals had a tab that interfaced with the rail to orient (on my NB1).

Let me close by saying that when I had the yellow tops, idling at 14.7 and 800 RPM, I would occasionally get a slight irregularity / roughness. Not enough to show on RPM log or gauge, but could be felt. ECU could detect it as the Spark Advance would move to correct.

With the FF, it is Rolls Royce smooth. Makes me want to try 750 RPM.

That was with connectors down. Today I'm going to eliminate the Denso connectors and aim USCAR connectors up for the ideal everything. EDIT: When I determine how I will keep them that way, I will post back.

Thanks Nigel.

Might be ghetto, but I feel like a simple zip tie under the connector and over the rail would work pretty well.

Looking forward to this :likecat: