tylink720

I only put in a 255. Yeah I thought it was strange too. I had seen lots of posts on here saying the stock reg was good for mild pump upgrades. Possibly the oem fpr was clapped the entire time and I only checked fuel pressure after installing a new pump

When I did my walbro swap, my base fuel pressure increased by about 10psi, which could affect fueling a bit. I had to get an aftermarket fpr bring it back to normal pressures

Lol I hope to take it out this weekend and rip it around. I’m curious to see how far off my fuel map is now that I’m running 10psi less base pressure. I do need to get a pressure sensor next season to keep an eye on it.

FIXED I installed the new fpr and turned it down to 43 psi. Idles nicely at 38ish psi now with the vacuum line attached. thanks for the help!

Stock rail but 1000cc Bosch injectors. Is there a reason for Tomei being junk? Seems like the easiest option since it has fittings and a mount already included

Any current recs for a good budget reg? I don’t want to buy some cheap eBay stuff, but also don’t want to drop $500 on just a regulator. I’ve seen some for about $140-$170 like Tomei, P2M, NRG, AEM, ect

Yep lol, half the fun is working on these piles. My brother has a newer BMW and it’s super quick and reliable

Alright, I've started looking for an aftermarket reg. This cars been a bottomless pit so far, and I haven't even started the proper power mods yet lol. thanks

Yep stock reg. Ill look into a new reg, just seems strange that it drops the pressure fine when I remove the return line. Also seen posts on here saying the stock reg is good for mild pump upgrades. It is 25 years old I guess

I don’t think it’s the FPR as I’ve run a short hose into a bottle straight off the reg, and the pressure drops down. Maybe a new reg is a good idea anyway though. I will try doing what you said and test down the line. Although the only spot I can measure is between the hard line and tank, but it’s cramped as in there. I’ll have to lower the tank to get in there. Yep I bypassed the dampener on the fuel return line too but didn’t help. I still have the dampener on the feed. Maybe I’ll test bypassing that one too as I put the gauge before it.

I've drilled out the siphon pump to a little larger than stock, I think I used a 5/16 bit. Put it back together and still had the 50psi fuel pressure. Took it apart again and ended up breaking one of the fittings on my fuel hat which sucked, but luckily I was able to get a new one within a week. Fit the new hat, and tested the pressure with the siphon pump removed so it just pumps straight back into the tank, still 50psi. I have to assume now it's my return line that's the restriction. I was hoping it would be easy to replace the rear fuel lines that connect to the tank, but it looks like I'd have to lower or drop the tank which looks like a crap job. I will try using an air compressor first to blast out the return line and see if it does anything

Sounds good, I’ll give this a try. Thanks for the help

Makes sense, I was thinking it had to be that thing. I will try modifying it first and see if I can get it to work. Is it drilling out the fittings on the hat, or drilling out the actual siphon pump?

Hey, is there a known restriction in the R34 GTT fuel return? I tested my fuel pressure with a Walbro 255, and have 52 psi at idle, with the regulator vacuum line on and off. The only time I get 43 psi is if I fully disconnect the return line off the regulator and let it flow out into a bottle, so it seems to be something after the reg causing it. I've disconnected both ends of the return line and I can blow through it. I went under the car and don't see any dents or kinks in the hard lines. I blew air into the return port of the fuel hat and it's harder to blow through, but I'm guessing that's because of that tank transfer valve attached to it. I’ve replaced the return lines from the reg to the hard lines as well Any ideas? Thanks

Just finished doing this on with my GTT with a Haltech, I ran a new shielded wire to Signal Ground, and used the oem wire for the other side of the plug