1 day ago in News
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Fuel injectors evolved over time, and as you might suspect, their spray patterns and level of atomization have improved with each generation. Here's what I'm talking about: http://www.youtube.com/watch?v=oxImoYMRUCA&feature=related
Guys who have played around with Miata injectors already know this; '99+ Miatas have a different shape injector body, and many have done that upgrade.
Injectors also come in different flow rates.
I recently upgraded mine and my dad's Escort's injectors to a set of EV6 units as used on the Mustang V6 and Windstar from about a decade ago. Same 19-lb/hr flow rate, newer design. We measured with a scan tool and confirmed long-term about a 5% increase in fuel economy. The electrical connectors were more or less compatible -- we had to break some plastic tabs and zip-tie the connectors down so they wouldn't vibrate out, but it worked. Some BMW E30 and Mustang owners seem to do this upgrade as well.
I recently found a crack in one of my injectors, so I figured now's the time to upgrade. I've done a lot of poking around and searching; unfortunately, the cheap and easy to find Ford injectors may not work. Miata injectors use that plastic spacer to seal the injector agains the intake manifold. Most other injectors use an O-ring. Otherwise, I think the length is the same.
So! Mazda injector geniuses! I want EV6 or newer injectors that will fit my 1.6L Miata. But not just fit: I want the same flow rate, too. I'm looking for a drop-in, no-hassle swap. No AFM tweaking, no Megasquirt, no adjustable FPR. This means injectors from a '99+ Miata won't work.
Does anyone have ideas? I think I found Ford SUV injectors with the right flow rate, but again, that plastic-spacer-versus-O-ring thing leaves me uncertain.
IIRC, the stock f150 v6 injectors were 19 lb/hr, what rate are you looking for?
I've found varying reports on 1.6 flow rate, from 212 to 235 cc/min. That's 20-22 lb/hr. 21 lb/hr would probably do the job, but again, I don't know if the Ford injectors will seal correctly against the manifold.
230 cc at 43.5 psi is what my notes say. 1999-00 stock injectors are 238 cc at 43.5, so they should be a drop-in.
The 1999-00 runs at a higher fuel pressure, that's why most people are confused about the injector rating.
Keith, I've been killing myself trying to find this information for months now. Hot, steaming crap, that's awesome. You are truly a god among mere Miata enthusiasts. Thank you so much.
Now I just need to find a set of those for cheap.
How to Build a High Performance Mazda Miata, page 67
Glad I could help. We have some salvage 99 injectors here for $60/set if that's the price range you're looking for.
if you have the ability to tune the ecu/megasquirt then check out the acura RDX injectors. they have great atomization and can support quite a bit of power. a lot of the N/A and lower boost turbo honda guys are using them these days
Keith, that's exactly the price I was looking for. I just called up Bill and ordered 'em. :)
Cool. And thanks, Keith. (By the way, Alan, Keith's books should be in my office.)
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