Z_WAAAAAZ

So a little while ago, I found myself troubleshooting an issue in my fuel system while laying the framework for my turbo NA8 build. I grabbed a DW200 fuel pump for my car, did the usual wiring/relay upgrade to run a higher flow pump, installed the pump and measured 145PSI on the feed line at idle. DAMN! I did a full diag of the return system and found the FPR restricting return flow. Installed a new FPR with the stock pump and got 35psi at idle with the vacuum line connected, 45psi without. Installed the DW200 after and got ~58psi with no change whether vacuum was connected or not. Confirmed that the vacuum line was sucking and not broken. Looks like the DW200 overpowers my stock FPR. Sweet...

While I was figuring out what to do about the fuel pump, my focus shifted to a different part of the build. I came across an MS3x for sale on the classifieds here and decided I'd take the opportunity while it was up for grabs. I dropped the OEM pump back in the tank and bought and set up the MS3x in my car. I've been getting familiar with Tunerstudio and playing with my fuel map for the last few weeks. Currently the car is hitting the AFRs I want to see and is driving quirk-free. Obviously, I now want to throw in bigger injectors! Based on my budget and power goals, I'm leaning towards FF640s.

Here's the crossroads I'm at: Based on the previous diag I did, it seems like the OEM FPR is overwhelmed by the DW200 pump at idle. After digging through numerous threads, I've put together two possible avenues for myself.

1. Drop the DW200 back in the tank. Install a Radium fuel rail and pressure regulator along with the injectors.
2. The stock fuel pump is enough for my power goals. Keep stock fuel pump installed. Install bigger injectors. Leave fuel rail and FPR alone. Spend the money I saved on other turbo project goodies.

What is everyone here running for fuel pumps/injectors/regulators on their 220-240whp NA8s?

SpartanSV

We can't know the answer to your question without knowing the fuel you intend to run.

curly

iTrader: (25)

At 220 I’m assuming pump gas and stock block. If I’m right, you’ll still want an upgraded pump. While stock pumps are supposedly fine, I’ve yet to see one keep up. I always monitor fuel pressure while dyno tuning, and although you can compensate with more duty cycle, I don’t like when my pressure drops.

you can put the dw200 in and tune around the high pressure at idle, it’s predictable. Or as you said, run a radium setup with remote regulator.

Z_WAAAAAZ

Damn and there I was thinking I had covered everything. Good point, I’m not planning on running e85, it’s almost impossible to find it in my area. Gonna be running 91 octane (yay, California).

Curly, thanks for the input. Yes, stock block for now. I hadn’t considered the possibility of simply tuning around the high pressure at idle. I’ll probably take a run at that and upgrade the fuel rail/regulator later down the road. Would rather keep fuel pressure consistent up top and eliminate another factor that needs compensating for.

Amped. Time to get me some injectors.

Z_WAAAAAZ

Update. Looking good.

I put the DW200 back in on my lunch break today. Started the car, 55psi on the feed line at idle. AFR in the ~11.5 range at idle after the car was fully warmed up. Went into the idle VE table and turned my idle numbers down until idle AFR was hovering around 14.0. Didn't touch anything else yet. Runs well, albeit AFRs run rich (~10-10.5) for a half second during throttle tip in from idle. Makes sense with the higher fuel pressure at minimal load. I'm sure I'll be able to tune that out over the weekend once I have time to do a little street tuning. Hopefully this thread helps anyone who has the same questions I did.

Anyways, one more piece of the puzzle in place! Injectors coming next. Or maybe new tires. New tires are probably more important before the car's next track day...