or you can just tap the stock rail to 1/4"npt then run line to a aftermarket fpr. heres my setup on my old sr.

 

I dont have crazy plans for power, just a mild build to around 250whp...nothing ridiculious. Boosted to around 10lbs. I figure stock SR injectors could handle the load (chime in if you feel other wise). I'll be searching on the topic to see what rail would be best to run. I like the idea of overkill on your part Empire. No harm in over building to make sure it lasts. Miataspeed...very nice set-up you had.

-Royce

 

Walbro 255 + stock fpr = fine 370cc injectors should be fine for a t25 on 10 psi. I'd put it up to 12, but that's just me.

 

+1 Aeromotive

 

I ran stock FPRs on all of my cars. I even had a Defi fuel pressure gauge on the fast car to keep an eye on it and it never had an issue.
- S13 with big Tomei pump and 740's
- S13 with Walbro and 370-480-550's
- S14 with Walbro and 550's
- S14 with TT Supra pump and 550's
All on stock regulator with no problems for over 7 years now.

That's a great tip, Miataspeed! I tapped the stock rail an inch back from there 1/8"NPT for the fuel pressure sender. Never had an issue and the rail was plenty thick right there.

 

Here is what I did...I picked up a stock FPR on the cheap @ Advance and installed it over the weekend. With the feed back I received here (thanks to all that contributed their advise), I decided to try replacing my FPR with a stock replacement. I didn't feel like waiting for more parts and was feed up with the car running terrible.

Once I installed the FPR (which is an annoying process on a KA by the way... replace the screws with 8mm bolts) and started the car the first thing I notice was that the car idled smoother. The second was the rich smelling exhaust had gone bye-bye. The third, acceleration is improved as well...no more bogging.

I hope this does last, at least until I start my engine rebuild. My valve seals are toasted as the car puffs a little smoke every once in a while when leaving from a stop light, or anytime I sit @ idle for any length of time. I'll be asking for input in that too. I just want a build that will handle boost in the 10psi range and be durable. I don't plan on doing anything other than an occassional twisty track day...the car is not a beater.

I'll keep you posted on how well the FPR holds up too.

Thanks,
-Royce