Do this if you want a slightly richer AFR for cheap!

[CustomMSP]

Install a fuel pressure regulator from a 2002 CA-spec'd emissions (might be the same as the federal spec'd or other years 626s) 626 FSDE, This brought my AFR down from ~12.3 to ~11.9 at redline on an otherwise stock tune and fuel injection system.

 

[Geezer000]

nice find.

 

[BOOSTR]

Did you put a brand new genuine Mazda FPR on?

 

[CustomMSP]

Did you put a brand new genuine Mazda FPR on?

Very good question. Both units are in perfect working order. I've done this twice with two completely different regulator sets.

 

[joka1]

I love simple/ cheap improvements............This may help out alot of members w/o fuel management!!

Rob

 

[Speed3.5]

Glad to read your still improving your MSP, Toly.

MSP goes richer than 11.9afr tho .... lol

 

[CustomMSP]

Glad to read your still improving your MSP, Toly.

MSP goes richer than 11.9afr tho .... lol

More like trying to not blow it up lol. They normally do, but not on my particular setup.

 

[CustomMSP]

I love simple/ cheap improvements............This may help out alot of members w/o fuel management!!

Rob

It's kind weird that a 626 would need a higher pressure regulator. But yea, I was glad to have discovered this a while back.

 

[grant_jr]

was it this?

go to onlinemazdaparts.com

02 mazda 626

Fuel system - Fuel induction - Fuel injection - Fuel pressure regulator

??

 

[CustomMSP]

I can try to get the part number tomorrow off of mine, but I got it off of a complete 2002 626 California spec intake manifold. It's much cheaper to get a used unit on ebay or other sources.

 

[grant_jr]

yea the ones on that site are $120

 

[HKPRO5]

sub.

 

[CustomMSP]

This is what I've discovered;

P/N: UC-PB1A FS05 (Mitsubishi)
Applications;

Mazda 626 GE 92-97 1.8 16V FP GE
Mazda 626 2.0
Mazda 626 96 2.0 4L
Mazda MX6 93-97
Ford Probe 2.0 93-97
MAZDA 93 MX6 fuel injector #INP-480
MAZDA 626 / MX-6 / PROBE 2.0 4L NIPPONDENSO ...
MAZDA 2.0 16V - RECON INJECTORS - 626 MX-6 - FORD PROBE
Mazda 626 1.8 16V 95 INP-480
Mazda 626 2.0 4 cil. <

According to this page: http://www.eter-mot.info/?1955,regu...ubishi-uc-pb1a-uc-pb1a-uc-pb1-a-br-denso-fs05

 

[Sport23]

subbin

 

[KrayzieFox]

I thought most of us were going for leaner AFRs.. how is this beneficial?

 

[destineal]

I was thinking the same thing.

 

[Carlinator]

I think he was running lean on his setup. He found a quick fix, so he posted it for others who might be in a similar situation. From stock, though, you're right, you wanna lean out.

 

[tweety2300]

12.3 is way too lean I had the same issue on my 323 and it was a vaccume leak fixed it and now it's at 11.3-11.6.

 

[Booski]

Quick question. What exactly is the stock AFR's? I was told it was really lean till like 4k, then after 4k it just dumps fuel like almost 9.5 to 1.
Is that correct?

 

[tweety2300]

Iirc 10.0-10.5

Ms3 runs in the 9s stock but it's direct injection so it's a bit different