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Hi,

As topic suggests I need the 13b turbo 460cc spray pattern changed to the same pattern as what the rb20det 270cc injectors spray at.

Does anybody know where i can get this done, or if i can get this done. Any one with experience with injectors or have had it done before. Also is it cost effective. i got the 13bt injectors for free..

Thank you in advance..

Daniel

bhadve,

reason to change pattern is because they were one direct squirt and were not atomising properly causing all little problems like not idling correctly..

They were in a rb20 with 242rwkw which has a few issues, changed injectors and problems went away..reason why i acquired them...

Thanks for the response, i might do what you suggest though i will look at other alternatives such as changing the pattern first..my plan is about 250rwkw out of an rb20 so I dont want issues straight away..

Cheers Daniel

I dont know was not on my engine...

I know it was tuned to the best it could be at the time. It was determined that certain issues were occuring due to the injectors having the wrong/ or a diferent spray pattern. This is as much i know of. I may be able to get a dyo chart for th specific run...

Daniel...

Thanx for the replys, though I am still curious to see if any one knows if it is possible to get the spray pattern changed???

I will give a few workshops a call during the week, just wanted to see ig anyone had feedback first...

Cheers

Advantage: They're cheap. Just make sure they are high impedence.

I'm not sure how you'd go about trying to change the spray pattern.

I found the s4 550's took a fair bit of tuning around idle and light throttle to get it smooth on my old rb20 but other than that they worked fine. I had them cleaned and a couple of pintle caps swapped as some were cracked when i bought them. As long as you don't expect to just chuck them in, adjust the injector correction value, and drive away they are fine.

The s6 ones in my rb25 were just chucked in, correction set and then a bit of light tuning in the idle region with an O2 sensor jammed in the exhaust and driven for a few weeks before getting the proper tune done.

A mate also installed a set of NA s5 injectors on his CA. Again, no problems. I'm pretty sure they were low impedence though, which is why you should check.

as far as i know you can't change spray pattern, unless of course they are dirty and can be cleaned to rectify the spray pattern fault. otherwise your stuck with what the injectors spray from factory/design.

some injectors spray better with more or less fuel pressure, you need to experiment on the bench to know what works best.

spray pattern should only make a difference on idle if you run full sequential injection timed to inlet cam opening duration, if you had an ecu that uses non sequential it will make two tenths of stuff all difference becauses its sprayed onto the back on the inlet valve and the hot valve helps it atomoize anyway.

The spray pattern of the rx7 550cc (Part # 195500-2020) is rather crap compared to the stock injectors.

When I watched them being cleaned and tested I noticed that they were more of a squirt than a spray.

Up side they are cheep and high impedance.

Down side is my idle is a little erratic.

When I watched them being cleaned and tested I noticed that they were more of a squirt than a spray.

Did the "squirt" fan out about 5mm when it just came out of the tip of the injector, then go into a solid stream? If so, they are meant to do that. When I got my injectors cleaned (RB30), they did the same thing. The guy cleaning said that is normal. When they are operating in an engine they are only on for a short amount of time, so the fuel doesn't get a chance to turn into a stream. Also, the air stream going past the injectors doesn't allow the fuel to get past the fan shaped spray.

GTR injectors FTW...

the spray pattern is perfect and they are easier to tune with due to the idle issues with the 550's and you can pickup a set for around $250

Yeah I tuned my brothers R32 with R34 GTR injectors and it idle better than it did with the stock injectors.

So yeah I am chasing a set atm.

Did the "squirt" fan out about 5mm when it just came out of the tip of the injector, then go into a solid stream? If so, they are meant to do that. When I got my injectors cleaned (RB30), they did the same thing. The guy cleaning said that is normal. When they are operating in an engine they are only on for a short amount of time, so the fuel doesn't get a chance to turn into a stream. Also, the air stream going past the injectors doesn't allow the fuel to get past the fan shaped spray.

Nah they were spraying lots of huge droplets everywhere rather than a fine mist.

Sorry I was being a little vague with calling it a squirt. :P .

mztrbo, why would you put in a set of injectors that had problems in a friends car? get them cleaned and tested etc.. if they are fine after that then put them in, from what ive heard many times again the "jet" at the base of the injector is different on the rotary injector due to the fact then when it sprays fuel into a rotary it has a shorter time to put in the right amount of fuel.. hence they squirt rather then atomise properly.

dead32,

first reason I got them for free?

Second reason, the car is not going to be a daily driver so ive already accepted the fact that it will idle like crap, the car it was in was tuned to idle higher then normal about 300-400rpm higher from memory and still use to hunt.

Thank for all th replys guys it has helped substantially..i think im not going to worry about changing spray patter, I have not even called an injector mob yet so that shows the lack of inititive...

Ive actually just purchased an rb25, so no more rb20...

Daniel

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