98 Fueling question with evap as the return
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From: Summerville, SC
98 Fueling question with evap as the return Does anyone have the fuel routing from the tank? The 98 has 4 ports coming off of the tank, feed, return, and i guess two evap lines. Anyone know for sure which one does what and where it goes?
The reason I ask is because I did a rail mounted boost referenced regulator and don't have any fuel pressure. I used the stock feed and used the evap as a return. We came to the conclusion that it is just bleeding off since I haven't touched the stock routing. So I have to cap the T and re arrange those lines, but I'm not sure which way to do it. Also for those of you that used the evap, did you keep the canister or remove it?
The reason I ask is because I did a rail mounted boost referenced regulator and don't have any fuel pressure. I used the stock feed and used the evap as a return. We came to the conclusion that it is just bleeding off since I haven't touched the stock routing. So I have to cap the T and re arrange those lines, but I'm not sure which way to do it. Also for those of you that used the evap, did you keep the canister or remove it?
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From: Dallas (Richardson), TX, USA
So, just to clarify, you didn't change anything but adding the FPR and using the evap line as a return? The stock pump is still in there with stock wiring, and you haven't disconnected/reconnected any of the lines going to the tank?
Also, what FPR did you use? I see that a lot of them have two feed ports. If you mistook a feed port for the return port on the FPR, then I would imagine it would just flow right through the FRP back to the tank without any resistance.
Also, what FPR did you use? I see that a lot of them have two feed ports. If you mistook a feed port for the return port on the FPR, then I would imagine it would just flow right through the FRP back to the tank without any resistance.
I may be wrong but if the factory reg. is in the tank and there is only two lines coming back from the motor ( 1 feed 1 evap) then the feed has to split some where near the tank to go to the factor reg. The pump is seeing resistance at the front and just feeding back in the tank. You need to find that (T) and block it or plug it in the tank where the factory reg. was.
This was posted on our other thread:
In order to bypass the stock return setup, you just remove that line coming from the T fitting going back to the tank and plug the T. It's an NPT fitting of some sort, but I don't know the size for sure. A quick search will probably reveal that answer.
In order to bypass the stock return setup, you just remove that line coming from the T fitting going back to the tank and plug the T. It's an NPT fitting of some sort, but I don't know the size for sure. A quick search will probably reveal that answer.
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From: Summerville, SC
walbro 255 pump
fuel rails
boost referenced regulator
I removed the stock fpr, took the extra hose off from the feed and evap ran the feed to the passenger side, crossovers in the rear, regulator is mounted on the rail. The boost is referenced from the housing on the turbo. The bottom port goes to the evap line. I changed the IFR and offsets to reflect the boost ref reg.
fuel rails
boost referenced regulator
I removed the stock fpr, took the extra hose off from the feed and evap ran the feed to the passenger side, crossovers in the rear, regulator is mounted on the rail. The boost is referenced from the housing on the turbo. The bottom port goes to the evap line. I changed the IFR and offsets to reflect the boost ref reg.
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From: Summerville, SC
The reason it is happening is because the lines have to be exchanged and the T has to be blocked. Steve (MeentSS02) helped me figure that out, I'm more so looking to find the path of fuel flow with those 4 ports on the tank.
He's got his lines routed correctly up front, and he knows he needs to cap off the T-fitting. What he's asking is what the 4 lines on the top of the tank are for (which is the feed, which is the return, which are for the EVAP system). I know what they are for a '99-'02 car, but I didn't know what to tell him for a '98 since they used a different tank.
My Helms manual is for a 2002, so it wasn't much help, and I tried searching. Someone has to know around here...
My Helms manual is for a 2002, so it wasn't much help, and I tried searching. Someone has to know around here...
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From: Summerville, SC
He's got his lines routed correctly up front, and he knows he needs to cap off the T-fitting. What he's asking is what the 4 lines on the top of the tank are for (which is the feed, which is the return, which are for the EVAP system). I know what they are for a '99-'02 car, but I didn't know what to tell him for a '98 since they used a different tank.
My Helms manual is for a 2002, so it wasn't much help, and I tried searching. Someone has to know around here...
My Helms manual is for a 2002, so it wasn't much help, and I tried searching. Someone has to know around here...
I pretty sure one of those lines for the evap isn't supposed to be removed and one of them is ok to remove to allow for venting. Just don't know which one
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From: Summerville, SC
I got it running and set the fuel pressure. Just so everyone knows, its a 1/4" NPT fitting to block off the T. I had to use alot of thread tape so it wouldn't leak.
I took out the pump to look inside and see what was what. Feed and return are obvious, then there are two ports for the evap. I capped the one with some cylinder underneath it and ran a hose down with a breather on it for the vented one. Now I have more fuel at idle since I have a steady 58psi. Rich as hell at idle now, 11.0-11.4
It's raining here so no logging for me. I'll have to wait until tomorrow I guess.
I took out the pump to look inside and see what was what. Feed and return are obvious, then there are two ports for the evap. I capped the one with some cylinder underneath it and ran a hose down with a breather on it for the vented one. Now I have more fuel at idle since I have a steady 58psi. Rich as hell at idle now, 11.0-11.4
It's raining here so no logging for me. I'll have to wait until tomorrow I guess.
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From: Summerville, SC
Teching In
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From: TN
Would this setup work for a carburated engine? I have a 2002 camaro,v6 car that i'm putting a smallblock in.I would like to keep the factory fuel tank and keep the fuel sending unit so the gauge would work.What regulator would you recommend?
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From: Summerville, SC
I'm not sure, you would have to get a regulator that can go low enough for the carbed fuel pressure. For using the evap as a return, I wouldn't see why not as long as you can find a regulator.
Teching In
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From: TN
thanks.I removed the tank and lines last weekend to try and figure out how to do this.I want to run the lines on the passenger side of the car up to the regulator and a return back to the tank if i can figure out where to hook it up.
sorry to dig but i to have a 98 ls1 f-body. would like to know how exactly you converted your EVAP line into a fuel return? if you could post some pics that would be great. tyring to visualize how to do this and just can get a clear picture.
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From: Summerville, SC
I don't believe I have any of the pictures any longer. I haven't had that fueling setup in probably 2 years.