Miata fuel system parts. Which fuel pump?

[Pyr0monk3y]

Hey fellas, I'm battling a hesitation and power loss issue on the track rat. I have gone through the usual suspects like plug wires, o2 sensors etc. I've diagnosed the problem as a bad fuel pump.

The car is at 203,XXX right now so I would like to have my injectors rebuilt and flow balanced at the same time.

Does anyone have a suggestion for a quality replacement fuel pump for a stock power 1991? I have no plans of boosting the car, if I apply any engine mods they will be spec miata legal. I found this kit from 949: http://949racing.com/Walbro-190LPH-HP-Fuel-Pump.aspx

I trust 949 and I have a principal of buying quality parts. I'm confident in the completeness of this kit and the quality of the parts, but I have a feeling it's overkill for a stock miata.

If anyone has experience having injectors worked, I would love some insight on where to send mine.

Thank you for your help.

[kung fu jesus]

There is a Walbro 190HP in my NA. I don't recall why I went that route, but I seem to recall it was made reputably versus the 255 and better suited my needs. At any rate, I replaced the sock at the bottom, too. Fairly simple, but I bought a separate, working assembly so I could get all the new parts on that and just drop it in the tank to minimize the fumes and exposure. Because of the facilities you have, I think you should drain the tank, flush it out, replace the pump and sock.

I have used a number of injector shops, RC Engineering, Witchhunter, Marren, and one that was in New England. I am sure there HAS to be one in NC/SC.

[kung fu jesus]

Quick, tertiary search...I never used them, but they have the same machinery every other place I've used has.

http://www.racecityinjector.com/

Idea: call for prices, see if they can do same-day. Drive down there (it's Mooresville!), drop them off, go to Simpson World, CV products, try on some suits and stuff for a frame of reference. Two birds, one stone.

[Agent☣Orange]

The 255 is overkill IMO plus it's loud but I suppose that wouldn't matter for a track rat.

[Hyper]

I drive an Aeromotive a1000 with injector dynamics 1000cc injectors. The trick to a reliable car with a big fuel pump is to rewire the fuel pump so that you get a constant 12 volt all the time instead of relying on the factory wiring to regulate the voltage at the pump. If you measure the length of the 16gauge wire that "possibly" begins from the battery to the fuse box, alternator, the PCM, to the ECU relays and sensors back to the fuel pump is a very long wire. You have to understand how voltage drops based on wire length and thickness. Adding a bigger fuel pump such as the 255hp complicates things more, depending on the size of the pump your factory fuel pressure regulator may not be able to handle the additional pressure, in the NB there are fuel dampers in the feed line for a reason plus the fuel pressure regulator is located inside the fuel tank. Just do your research and learn what needs to be done before you proceed. Good luck.

[Pyr0monk3y]

I pulled the trigger on a Denso kit. From my research I understand that Denso made the oem fuel pump and it's a quality part. The kit includes the pump, the strainer, some bits of wiring and other random shit.

KFJ, would you place any extra value on a service that's miata specific? For example, I talked to a place that claims that they rebuild and flow test your injectors, but the injectors you get back wont necessarily be yours. They have an inventory of injectors and they send you 4 that have nearly identical flow.

[Demon I Am]

Most injector shops run like that, from my research.

[kung fu jesus]

Technically, no I don't. You could buy the pintles and o-rings and do them yourself with some sort of rig.

If getting yours back matters that much, drop off and pick the same day.

[JLBMX5]

Ive had a hesitation that i get somewhere between 3 and 4 thousand rpm when in acceleration. Its not all the time . Well the other day when it was 9 degrees out at 6am my battery died. I knew it was going south because every morning the car was hard to start. Also with my alarm when doors are open it makes turn signals blink and when that happenend the interior lights would dim. Well after new battery no more dimming light. No more hesitation and i seem to be bouncing off the rev limmiter alot sooner i must of had low voltage for awhile and did not know it.