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Just wrapping up an LS3 swap into a '94 TransAm. Got it started and running fine, even drove it around the block. One of the few remaining issues is my fuel pressure is at 70 psi. My fuel system looks like this:
stock tank and sending unit
Walbro 255 pump with Racetronix pump harness and upgraded bulkhead harness
stock lines including return line from engine bay
stock fuel filter delete
MasterPro (O'Reilly's brand) Corvette fuel filter/ regulator mounted in engine bay
Stock LS3 fuel rail
The fuel pressure gauge is an Auto Meter digital gauge I've had for years.
The car is running fine but on my logs it's clearly pulling fuel to compensate for the higher pressure. Not sure what I can do other than try a different FPR/filter. There aren't any constrictions that I can see.
Here is the stock filter delete and my FPR/ filter set up under the hood. These are the only places I messed with anything.
Just did a search and all of a sudden these filters are just gone?? I bought this one for like $30 and there were plenty more to choose from but now all the auto parts stores are out. What the heck happened in the last month??
From: Halfway back on the Highway to Hell...again!
The filter should be as close to the tank as possible. Not sure if that's the reasoning of the high pressure. But still needs be be near tank.
You may just have a defective filter/regulator
It looks like Speedway Motors has them under their brand. Don't know who supply them to Speedway. A Wix or Delco is going to be closer to $100.
Maybe Rock Auto?
I managed to get an ACDelco GF822 from O'Reilly's for $117. Couldn't find a Wix anywhere. Looks like there might be a few different ACDelco filters: ADO-GF822, ACF-GF822, and ACD-GF822. Don't know what the difference is.
When I buy a Wix or a Delco I just tell the parts person I need a FFR for a 2003 Corvette.
Just note. I looked at the first pic above of the fuel line connection using the plastic retaining clip. I would safety wire it so if the plastic clip fails the fitting can't come off the connector.
I'm not a big fan of the FFR with the -6 fittings. The reason being is if it fails you can't just go down the local parts store and get another.
Just one more thought. You said you have a fuel pressure gauge but just to confirm fuel pressure I would check it at the fuel rail with a pressure checker. Oreilly's has them as a loan out tool as do other parts store.
The filter should be as close to the tank as possible. Not sure if that's the reasoning of the high pressure. But still needs be be near tank.
You may just have a defective filter/regulator
Swapped in the ACDelco FFR and no change, still 70 psi. Why mount as close to the tank as possible? My old LT1 had the FPR mounted to the intake manifold. I'll try running a 2ft long return into a jug. If that works then I'll have to rethink my whole fuel system...
Why would that work? What's different about this FFR vs my LT1's FPR?
In the mean time I'm going to change the flow rate vs kpa table to adjust for the extra pressure.
When I went to take the return off the FFR this is what I found.
Not sure how or why those got there but even with them removed my fuel pressure is still 70 psi with a line going into a jug. And remember this is my 2nd FFR so I'm extra confused as to how they got there.
That's not the return line.
Did you use the AN fitting repair disc?
That metal looks like it could be one of them.
We use red and black fittings to differentiate the flow paths.
The middle is 5/16 and the outer is 3/8. I did not use an AN repair disc, there are no AN fittings in my fuel system. It's all quick disconnect and nylon lines.
how many adapters/compression fittings do you have in the return line. If the return line isn't big enough, the pressure will be high. If you look at the internal diameter of the those types of compression fittings/union, they are really small compared to the internal diameter of the actual hose.
Every FPR like that, stock or aftermarket I've seen, says to mount it as close to the tank as possible. I know Holley mentions it in their instructions.
Without checking the fuel pressure on the return side, there's no way to know for sure if that's the issue.
how many adapters/compression fittings do you have in the return line. If the return line isn't big enough, the pressure will be high. If you look at the internal diameter of the those types of compression fittings/union, they are really small compared to the internal diameter of the actual hose.
Every FPR like that, stock or aftermarket I've seen, says to mount it as close to the tank as possible. I know Holley mentions it in their instructions.
Without checking the fuel pressure on the return side, there's no way to know for sure if that's the issue.
Return line currently just has one nylon line union in place. When I was running the LT1 I had two unions, some extra line and a fluid cooler in the return loop. No fuel pressure issues. I think I'm going to use my air compressor to blow out the lines in case any debris is wedged in there. Then I'll have to brainstorm a way to check pressure in the return line if that doesn't clear anything out.
As far as mounting as close to the tank as possible, the stock Corvette mounting location is on the frame way up next to the bell housing.
I had the same problem with my Corvette filter/regulator install. The fuel pump would override the FPR. It was a Racetronix 340 LPH pump though. Tried several Corvette FPR´s
Ended up installing an aftermarket FPR on the fuel rail end.
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Fuel Pressure at 70psi 
Someone is 
