I have recently replaced my primary fuel injectors (old ones 550cc, new ones 550cc) and now I am seeing that my A/F ratios (LM-1) are about .3 to .5 richer all the way across the map, sometimes a touch more.

I think it could be due to the old injectors were starting to get clogged up, not good spray pattern, and just plain old.

Opinions and thoughts please.

 

That's very possible. Spray pattern is a BIG deal with injectors - the better the pattern, the better atomization you get of the fuel and more efficiently they work.

Did you get them new from Mazda?

Dale

 

New from the Rx7Store.

 

On the subject of injectors, are there newer injectors available for our cars that might have better flow patterns? I'm sure that things have progressed in the past 10 years. I wonder if the injectors from the '02 RX-7s use the same exact injectors as ours...

I've searched briefly for info on the RX-8 injectors flow rates, but couldn't find anything. I'd also be somewhat surprised if they were a simple plug-and-play swap.

Has anyone got alternative injector ideas?

-s-

 

Did it improve light throttle response and cruising smoothness at all?

 

The RX-8 injectors are bigtime not a swap-in. Not only are they smaller, they're a very different design. I think they're top feed as well.

That's a really good question as to newer-design side feed injectors. I had a set of Delphi injectors in my old '88 TII that used the ball/disc type tip - supposed to give really good atomization and good injector control.

Heck, I'd like to know if there's a good source for "plain" 550cc side feeds that are reasonably priced! You can clean injectors, but in many cases there's nothing like a brand-new injector. Not to mention many have had trouble with cleaned injectors locking up and whatnot - don't have a lot of personal experience there, though.

Dale

 

Just found -

http://www.nolimitmotorsport.com/prod/BZ-31229

Blitz makes side feed 550cc and 850cc injectors. I'm sure they're just grabbing Nippondenso parts. But, $133 for a new injector is pretty damn reasonable.

You'd have to ask if they fit the FD fuel rail properly, though. I know SR20DET's use side feed injectors VERY similar to the FD's. They may be listing them for that application, hard to say.

Dale

 

with the blitz units they come with a new clip for the injector also. which is nice especially if the injector is leaking and the plastic suks on the harness. they are just rebadged nipp parts. but you cant beat the price. i liked mine

 

Cool, so they ARE drop in replacements for the stock injectors? Both 550's and 850's?

If so, that's a VERY good thing to know. Mazda wants a pretty penny for the injectors! Nothing wrong with getting the EXACT same injector that's brand new!

Dale

 

cant speak for the 850 but the primaries def. blitz is not making anything but they take a smaller margin than the dealer

 

Sorry busy weekend guys.

No it made it worse. I never had light/cruise throttle problems. I now have a stumble at cruise and I know that is because my A/F ratios are too rich. I have been slowly backing them down in those areas. It is helping. Idle is also still too rich.


The Blitz injectors had the exact same number on it as my old ones. They fit like a glove in the rail (just add a touch of vaseline). I would think the 850s would be the same way, but I only bought the 550s.


Thanks

 

Ok, thanks for the follow up. I was more curious about cleaned injectors running on the stock ECU.

<hey, I hear you giggling, it's not funny>

Dave

 

At some point, the JDM RX-7s went to 850cc primaries.