n/a-luvr

Ok guys, my orginal post created a war zone when I felt the car was running lean and asked for advice on putting 550cc injectors in the primaries... There ended up being 2 sides:

1. "RX7's run rich already - leave well enough alone"
2. "The car is running lean - go for it"

Come to find out both sides were right, sorta - while I had the UIM off to fix the leaky PD, I found why I was running lean: Bad injector boss seals, bleed socket seals, a cracked bleed socket face and RTV'd intake gasket.

Can you say vacuum leaks?! Since replacing, I'm now running richer and have actually lost acceleration plus my exhaust is no longer loud as F***. On a positive note the car idles better... Step 2 is to replace my secondary injector seals and bleed sockets which were found to be a solid mass of carbon! My long-term plans are still to run the 550's as primaries but only after I buy a stand alone to reduce their output. ~rich

Syonyk

And I believe a number of posts were, "If you're running lean, you have serious problems. Fix them." I'm glad you found out what was causing the trouble. Now the 460s should run you wonderfully, if still a bit rich.

A standalone is a good option, but I still don't understand why you want to put the 550s in the primary position. The smaller the primary injector, the more precise the fuel control at low flow rates, which is where it matters. By the time the secondary injectors come online, there's so much air/fuel flow that the lack of precision doesn't matter.

And, yes, FCs tend to idle happier with a bit of fuel added. The only place in my SAFC-II map I add fuel is at idle. Though, honestly, it seems to be happy idling somewhat leaner as well, as long as it's warmed up.

-=Russ=-

n/a-luvr

Well, I'm kind of waffling over what to do. The more time I spend on the car, the less satisfied I become with the intake design and the more motivated I become to make a custom setup.

If I remember correctly, the low-impedance injectors have a faster response time than the high-impedance. Orginally, I was experiencing a lean condition before the 3.8k secondary kick-in point and didn't know if it was cause of the mods done to my engine....I know better now...But at the time was hoping the 550's would correct it.

However, I'm missing the oompf from running lean but don't have the cash for goodies right now - mebbe I'll adjust the secondaries somehow to allow more air in? Dunno - lemme think about it. Right now the 550's are sitting brand new in the box. ~rich

Syonyk

Have you considered a SAFC-II or such device? You can probably get a used one for around $150, and it'll let you lean things out up high. My entire map (with the exception of idle) is pulling out fuel, and above 5000 RPM I'm pulling out a LOT of fuel.

-=Russ=-