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Mazda 13b/20b 550cc Injectors Into Rb25det

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Is anyone on here running these?

I'm currently looking at upgrading as per this post:

http://www.nissansilvia.co.nz/OldWebsite/t...0Binjectors.htm (site off line atm)

And they point out there are a couple of issues with the collers, which are easily overcome.

but just wondering who has used these, and what there thoughts and feelings are on them. Seems to be a good cheap upgrade. Any extra info would be appreciated aswell.

Cheers Guys!

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um i was going to do this the hardest thing was trying to find a good cheap set, you also need to change the injector plugs, and rx7 injectors dont have the best spray pattern they just dump fuel. But see how you go.

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In terms of fuel spray pattern, the rotory injectors essentially just squirt the fuel in a line.

Speak to red drifter after tuning issues associated with running 13b injectors.

There was a thread a while back about modifying the tip of the stock injectors - removing the tip (forgot the technical term - too tired). It will give you a similar outcome, without the troubles of chopping and changing plugs etc

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I run them, they work. Same as blitz 550 injectors if anyone is interested.

You need to trim a lip off the bottom screen and swap the plugs to a standard denso type. You need collars the same as sards. Because the bottom o ring sits low on the injector you need to be very careful installing them in the rail so that you dont pinch it (use petroleum jelly).

Otherwise, they are fine.

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Another option you could look at is getting high flows from deatschwerks. Last set of 13b injectors I saw were around $300 or so if I remember properly, whereas deatschwerks only charge around $600 (cant remember exactly how much I paid as it was quite some time ago) and then when you receive their injectors, you send your old stock ones back to them and they give you a rebate. Unless the 13b injectors have been ultrasonically cleaned and flow tested I would go the deatschwerks as the extra pieces + messing around involved in the 13bs, combined with the fact you are getting an old injector that you will have to get cleaned and tested (well not have to, but I would advise it) amounts to a higher cost, higher risk and more effort which IMO isn’t worth the $200 or so you will end up saving (depending on what must be done, purchase price etc). Some people don’t like high flows, but I’ve used them on 3 cars and they have all performed beautifully and drop straight in.

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i can get 3 20b injectors for 150, 6 for 300-350, so quite cheap but yes have to get collars and plugs need trim...

am now looking at different alternatives. 98 Legacy twin turbo injectors fit, just need to use an extra O-ring, think they are about 440cc, there is a guy over here using them and getting 300rwkw. I'm also trying to find S15 Spec R (manual) injectors which are 480cc and bolt straight in. but they are hard as crap to get!

Is there anyone else out there using anything interesting as a cheap upgrade? Share....

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They are Denso injectors. Spray pattern is actually very good when they are clean. I was previously running S5 550's in my 26/30. You can obtain the injector plugs off most toyota corolla's. As far as fitting in the rail goes, they do fit but the O rings are not interchangeable from your 20/26 injectors, the 20/26's run a slightly fatter O ring which will actually get the rx7 injector stuck in the rail if you use them despite that fact that you can get them on there.

There also hi imp so remove the resistor pack if going into a GTR, and lastly make sure you have them cleaned and flow tested before fitting. Its not uncommon to get maybe 2-3 in a complete set that are seized.

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