Fuel Return Line and EVAP Strategy
Thread Starter
Teching In
Joined: Aug 2002
Posts: 47
Likes: 0
From: San Jose, Ca.
Fuel Return Line and EVAP Strategy OK, now I have a better understanding of the existing LS1 fuel system but I don't know what approach would be the best for adpating the LS1 requirements to my Chevelle. For example:
1) The LS1 uses a semi return system. So if I can see the exisiting feed line going to the fuel damper do I simply apply a feed line from the tank => primary filter => pump => secondary filter => regulator => fuel damper as before? And the "return line" attaches to the output side of the regulator? Can it be that simple?
2) Also is it worthwhile to use the EVAP valve assembly and the Chevelle's EVAP cannister? Or can I simply plug it off? Is there any danger in not using the EVAP system?
3) There are a number of pumps, filters and regulators available. Any recomendations by manufacturer and part number? I've used Aeromotive in the past as they're very reliable but not cheap.
1) The LS1 uses a semi return system. So if I can see the exisiting feed line going to the fuel damper do I simply apply a feed line from the tank => primary filter => pump => secondary filter => regulator => fuel damper as before? And the "return line" attaches to the output side of the regulator? Can it be that simple?
2) Also is it worthwhile to use the EVAP valve assembly and the Chevelle's EVAP cannister? Or can I simply plug it off? Is there any danger in not using the EVAP system?
3) There are a number of pumps, filters and regulators available. Any recomendations by manufacturer and part number? I've used Aeromotive in the past as they're very reliable but not cheap.
Staging Lane
Joined: Apr 2003
Posts: 62
Likes: 0
From: Jacksonville, FL
Re: Fuel Return Line and EVAP Strategy Here is a picture of the setup I'm going with. High pressure line from the in tank pump. Aeromotive fuel pressure regulator set to 58psi and a return line back to the fuel tank for the un-used fuel. Pretty standard setup and a duplicate of the fuel system in just about every modern EFI car.
Here is a pic:
http://www.irondonut.com/personal/be...22_medium.html
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fastlane68:
<strong> OK, now I have a better understanding of the existing LS1 fuel system but I don't know what approach would be the best for adpating the LS1 requirements to my Chevelle. For example:
1) The LS1 uses a semi return system. So if I can see the exisiting feed line going to the fuel damper do I simply apply a feed line from the tank => primary filter => pump => secondary filter => regulator => fuel damper as before? And the "return line" attaches to the output side of the regulator? Can it be that simple?
2) Also is it worthwhile to use the EVAP valve assembly and the Chevelle's EVAP cannister? Or can I simply plug it off? Is there any danger in not using the EVAP system?
3) There are a number of pumps, filters and regulators available. Any recomendations by manufacturer and part number? I've used Aeromotive in the past as they're very reliable but not cheap. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Here is a pic:
http://www.irondonut.com/personal/be...22_medium.html
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fastlane68:
<strong> OK, now I have a better understanding of the existing LS1 fuel system but I don't know what approach would be the best for adpating the LS1 requirements to my Chevelle. For example:
1) The LS1 uses a semi return system. So if I can see the exisiting feed line going to the fuel damper do I simply apply a feed line from the tank => primary filter => pump => secondary filter => regulator => fuel damper as before? And the "return line" attaches to the output side of the regulator? Can it be that simple?
2) Also is it worthwhile to use the EVAP valve assembly and the Chevelle's EVAP cannister? Or can I simply plug it off? Is there any danger in not using the EVAP system?
3) There are a number of pumps, filters and regulators available. Any recomendations by manufacturer and part number? I've used Aeromotive in the past as they're very reliable but not cheap. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Staging Lane
Joined: Apr 2003
Posts: 62
Likes: 0
From: Jacksonville, FL
Re: Fuel Return Line and EVAP Strategy I missed the last two questions.
#2) I don't know the answer to the evap system question. I'm blocking mine off for the first try.
#3) Nothing works like the factory gear. I'm going with a standard F-body fuel pump. If you want one I have an extra. Let me know.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fastlane68:
<strong> OK, now I have a better understanding of the existing LS1 fuel system but I don't know what approach would be the best for adpating the LS1 requirements to my Chevelle. For example:
1) The LS1 uses a semi return system. So if I can see the exisiting feed line going to the fuel damper do I simply apply a feed line from the tank => primary filter => pump => secondary filter => regulator => fuel damper as before? And the "return line" attaches to the output side of the regulator? Can it be that simple?
2) Also is it worthwhile to use the EVAP valve assembly and the Chevelle's EVAP cannister? Or can I simply plug it off? Is there any danger in not using the EVAP system?
3) There are a number of pumps, filters and regulators available. Any recomendations by manufacturer and part number? I've used Aeromotive in the past as they're very reliable but not cheap. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
#2) I don't know the answer to the evap system question. I'm blocking mine off for the first try.
#3) Nothing works like the factory gear. I'm going with a standard F-body fuel pump. If you want one I have an extra. Let me know.
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Fastlane68:
<strong> OK, now I have a better understanding of the existing LS1 fuel system but I don't know what approach would be the best for adpating the LS1 requirements to my Chevelle. For example:
1) The LS1 uses a semi return system. So if I can see the exisiting feed line going to the fuel damper do I simply apply a feed line from the tank => primary filter => pump => secondary filter => regulator => fuel damper as before? And the "return line" attaches to the output side of the regulator? Can it be that simple?
2) Also is it worthwhile to use the EVAP valve assembly and the Chevelle's EVAP cannister? Or can I simply plug it off? Is there any danger in not using the EVAP system?
3) There are a number of pumps, filters and regulators available. Any recomendations by manufacturer and part number? I've used Aeromotive in the past as they're very reliable but not cheap. </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">
Re: Fuel Return Line and EVAP Strategy I connected the EVAP on my car and it works fine. Won't cost you any HP so why not! Won't hurt to not use it but your fuel tank will see high pressures inside.
As for a fuel pump I use a Walbro 340 and it works great!
<small>[ April 20, 2003, 08:24 PM: Message edited by: John B ]</small>
As for a fuel pump I use a Walbro 340 and it works great!
<small>[ April 20, 2003, 08:24 PM: Message edited by: John B ]</small>
Teching In
Joined: May 2002
Posts: 25
Likes: 0
From: Kiel, WI
Re: Fuel Return Line and EVAP Strategy here is a pic of mine. its a fbody link so you have to copy and paste on your browser. http://www.fbody.com/members/LS1IROC...fuelrails1.jpg
I use the factory fuel supply line run up to the engine, Y off to each side of the new fuel rails, connect the returns of the fuel rails together in a Tee, then that line runs to a pressure regulator. The other side of the regulator is capped off, and the return line from the regulator is hooked to the return line to the tank.
I have my evap line from the fuel tank hooked up to the evap sol. on the engine.
there are lots of pics and explanations on my web site
I use the factory fuel supply line run up to the engine, Y off to each side of the new fuel rails, connect the returns of the fuel rails together in a Tee, then that line runs to a pressure regulator. The other side of the regulator is capped off, and the return line from the regulator is hooked to the return line to the tank.
I have my evap line from the fuel tank hooked up to the evap sol. on the engine.
there are lots of pics and explanations on my web site
