No, I have a return system. If you bolt the 90-97 NA FPR to the 99 fuel rail (bolt-on) it becomes a return fuel rail. I only run the 99 fuel rail because I have a 99 head - there is nothing special about the 99 fuel rail.

There are 2 NB fuel rails, I'm assuming this is the one with the pulsation damper on the FRONT of the rail, right by the throttle body?

yes.
didn't know there are 2 different NB fuel rails.

Interesting.. It looks like the 99 pump is a total POS.

On a side note, in regards to the 90-97 cars.. "Other than that, you don't need one. If you have an aftermarket ECU, the stock pump more than enough to support 300rwhp with the stock regulator"

That being said, I agree with the others that OP needs a new pump. All this talk about pumps has got me looking at a walbro255 upgrade for my new 1.8 build as well.

Yeah, I believe they are referred to as "early" and "late" though there is no change in the part number or documentation that I've seen from Mazda. Anecdotal evidence says the changed happened sometime in the 2000 model year production cycle. The NB rails "should" be interchangeable from 99-05, but its only the earlier ones that you can replace the damper with a 90-97 FPR. There are pics here on MT, I just can't remember where exactly I saw them.

IIRC that's more a function of the vac/boost reference 90-97 factory 1:1 FPR than the quality of the 90-97 factory pump. Remember 99-05 is non-return and non-vac/boost referenced so in an NB, 5psi in the manifold means you have 5 LESS psi fuel pressure. Push that up to 10 or 15 psi of boost and your 650cc injectors are now magically 563cc. That surprise @ 15psi is no bueno.

So if i get you guys, i'm better off with a return system?

Return is better but its not required at <300whp. If your waiting until next winter before you build your engine then it wouldn't hurt to wait but if you have time to kill just go with it. I'm running a 255 with a returnless system on my 99 and even though i'm only pushing 250whp, I've never had any problems with it. Btw I love the way your build is going and it looks great!

fromwith the NA.

The time i don't have it, i have to make it :bang:

Deatschwerks 700cc or RX-8 450cc

i'm affraid the 700cc could be too much for my setup?

There is no such thing as too much. Get the 700's!

Even knowing that i'll keep stock 60psi fuel pressure?

Buy once and get the biggest fucking injectors possible.

Also get a bigass fuel pump. I thoroughly recommend nothing less than two Bosch 044 pumps in tank each feeding their own A1000 pump. Each pump should go to each end of the fuel rail.

This should be enough fuel for 300hp.

i'm affraid that the 700cc will be hard to tune idle/cruise.
because i don't plan more than 10-12psi for this summer even next summer.
The walbro 255 is on the list.
Because keeping the 60psi stock pressure, the 450cc would be about 525cc, wich would be enough for my setup. the 700cc@60psi would be almost at 800cc wich would be way overkill.
i get the buy it once/buy it big, but i don't want to have problem tuning fuel next summer, i already had problem last summer with idle drop, lean and rich spot(voodoo box)

You should have no issues with a 1000cc injector IF:

• You have an ECU with high enough resolution (IE:MS2x or better)
• You are using a quality low latency injector (FIC or ID EV14 style injectors or GTFO)
• You are using proper ECU settings for above injectors (latency/deadtime/voltage correction/etc)
• You have sequential injection (with an NB you should already have this)

Having said that, I'll be running FIC 650cc EV14 injectors on my car, because:

plus I got a hook-up deal through a vendor here on MT for my FICs. :giggle: @ 50psi (assuming stock 60psi non-referenced regulator and 10psi of boost) my 650's are closer to 700's and should be good for something silly like 450hp. If I make 1/2 of that I'll be happy, but its good to know I've got the headroom. I also expect to NEVER have idle issues once I get the proper settings into my megasquirt.

Notice: EV14 1150cc, Megasquirt MS2, idling



:2cents: There are very few people I will blindly take advice from on this forum. Reverant is one of them as is Savington (Trackspeed Engineering) and Emilio700 (949Racing). Rev builds ECUs and Sav & Emilio race the shit out of these cars pretty much for a living. Do a couple of searches and see what they (and everyone else) recommend and then spend your dollars accordingly.

Wow! thanks man!
Cause i'm searching for power, but mostly to have a stable, good running car.
Budget is one thing, but i'm ready to pay more for the good stuff!

By low latency you mean low resistance/low Impedance ?

lower deadtimes = low latency = faster responding injectors = more precise control. This is what makes the EV14 so desirable.

Speculation:
High impedance / low impedance shouldn't matter, provided your ECU can properly drive them. The Miata uses high impedance/resistance (saturated) injectors, so that's what I purchased.

That is not what i call much more expensive, a few bucks more than the 450cc rx-8 denso injectors, and about the same as the deatchwerks.

I started to gather some parts
All still in Order/shipping.
-Reverant MS3
-FIC 650cc Injectors
-Walbro 255
-Turbosmart Boost controller
-STRI DSD-SLM Fuel pressure gauge

I still hesitate for fuel rails, FM kit or M-Tuned.
Both cost around the same if i go with braided fuel lines for the M-tuned.

I also have to make a pod to fit the FP Gauge, wich i think is going to go under the radio.

Why fuel rail?