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Vapor Lock - 1971 Satellite 318 Looking to install a Fuel Vapor Separator, Need some Direction

I've been thinking about getting the stock vapor separator (with correct orifice) and put in a new line and fuel sender. But I'm wondering if I need to then add the 440 fuel pump vs the 383 one that I have now. The 440 fuel pump has a 3/8 nipple from the fuel line and the 383 fuel pump has a 5/16 nipple. When I got the car it had the 440 fuel pump and the fuel pressure was too high to the carb. When I switched to the 383 fuel pump, psi is at about 5 or so and car is very happy. I think I'm right in that the 440/Hemi had the 3/8 fuel line and sender from the tank and the 383 had the 5/16 fuel line and nipple on the fuel sender and fuel pump.
Basically wondering if the addition of the return line with stock vapor separator warrants a higher output fuel pump. Hmm...
 
Thing is when running the vapor separator you eliminate the fuel filter so the only filter is the screen in the carb inlet....

The Wix filter is a filter with a 5/16 inlet & outlet plus the 1/4" return... It's cheap so you don't mind replacing it where as the vapor separator is pricy and doesn't filter the fuel.... Unless you are trying to impress an OE judge I would have a hard time running one...
 
Thing is when running the vapor separator you eliminate the fuel filter so the only filter is the screen in the carb inlet....

The Wix filter is a filter with a return, and a 5/16 inlet & outlet plus the 1/4" return... It's cheap so you don't mind replacing it where as the vapor separator is pricy and doesn't filter the fuel.... Unless you are trying to impress an OE judge I would have a hard time running one...
I have two vapor separators that are correct repros. I'm kind of committed but you make a very good point! :)
 
I have two vapor separators that are correct repros. I'm kind of committed but you make a very good point! :)
I have a correct repo too, and a car that originally came with a vapor separator.... Still don't know if I will use it when the car gets back on the road....
 
I have a correct repo too, and a car that originally came with a vapor separator.... Still don't know if I will use it when the car gets back on the road....
IMO, the WIX filter with the 1/4" return sends too much fuel back to the tank starving the Carburetor. Some of those repo separators have the 1/4" return also but the correct ones have a smaller orifice regulating the fuel that it sends back to the tank. Mopar fixed the vapor lock problem for us back in 68 when they developed the separator and return line feature. Yeah, they cost more but how much grief do you want to put up with? Seems like everyone with vapor lock problems want to deal with it by trying every trick in the book except the one that designers gave us for free. I learned of the problem back in 68 when my Charger R/T never vapor locked while my Brother's 383 car did. When we did our research we realized the problem and found a wrecked Hemi Charger in a junk yard. Swapped in the 3/8 sender, lines and separator and the problem never arose again. We decided the fuel was boiling in the fuel pump from the engine heat and reasoned that was why the factory gurus mounted the separator at that location.
 
IMO, the WIX filter with the 1/4" return sends too much fuel back to the tank starving the Carburetor. Some of those repo separators have the 1/4" return also but the correct ones have a smaller orifice regulating the fuel that it sends back to the tank. Mopar fixed the vapor lock problem for us back in 68 when they developed the separator and return line feature. Yeah, they cost more but how much grief do you want to put up with? Seems like everyone with vapor lock problems want to deal with it by trying every trick in the book except the one that designers gave us for free. I learned of the problem back in 68 when my Charger R/T never vapor locked while my Brother's 383 car did. When we did our research we realized the problem and found a wrecked Hemi Charger in a junk yard. Swapped in the 3/8 sender, lines and separator and the problem never arose again. We decided the fuel was boiling in the fuel pump from the engine heat and reasoned that was why the factory gurus mounted the separator at that location.
The Wix filter has a .060 orifice in the return nipple... The early repo vapor separators did not & that's the ones known to cause a lean condition....

Add a #60 Holley main jet in the return hose & problem solved....
 
The Wix filter has a .060 orifice in the return nipple... The early repo vapor separators did not & that's the ones known to cause a lean condition....

Add a #60 Holley main jet in the return hose & problem solved....
Good info. If the ones I put in dad's truck gives me any trouble at least I know what to try.
 
The Wix filter has a .060 orifice in the return nipple... The early repo vapor separators did not & that's the ones known to cause a lean condition....

Add a #60 Holley main jet in the return hose & problem solved....
Would you happen to know what the WIX number is with the orifice in it? My 68 R/T 440 is having these issues and would like to be able to drive it in the summer.
 
WIX 33054
I looked up the filter and Amazon said it fits a 1980 dodge aspen. Of course now I need to research the aspen fuel system since I love this stuff!
 
I looked up the filter and Amazon said it fits a 1980 dodge aspen. Of course now I need to research the aspen fuel system since I love this stuff!
It was OE on most Mopar V8's from around 1978 till EFI came around... They saw the positive value in eliminating Vapor Lock which was getting to be more of an issue with stuffing more stuff under the hood & running hotter to reduce emissions...

The filter has a 5/16" inlet & outlet plus a 1/4" return line to the fuel tank...

A 68 440 R/T should have a 5/16" fuel supply line, In 69 I've seen 5/16" and 3/8" by 70 3/8" is standard with a 440... But whether the supply like is 5/16" or 3/8" after the fuel pump they all including 70 & up use 5/16" so the new filter works & solves vapor lock issues...
 
It was OE on most Mopar V8's from around 1978 till EFI came around... They saw the positive value in eliminating Vapor Lock which was getting to be more of an issue with stuffing more stuff under the hood & running hotter to reduce emissions...

The filter has a 5/16" inlet & outlet plus a 1/4" return line to the fuel tank...

A 68 440 R/T should have a 5/16" fuel supply line, In 69 I've seen 5/16" and 3/8" by 70 3/8" is standard with a 440... But whether the supply like is 5/16" or 3/8" after the fuel pump they all including 70 & up use 5/16" so the new filter works & solves vapor lock issues...
Awesome! I’ve got a new sending unit with a return connection and 3/8 ready for my next empty tank.
 
IMO, the WIX filter with the 1/4" return sends too much fuel back to the tank starving the Carburetor. Some of those repo separators have the 1/4" return also but the correct ones have a smaller orifice regulating the fuel that it sends back to the tank. Mopar fixed the vapor lock problem for us back in 68 when they developed the separator and return line feature. Yeah, they cost more but how much grief do you want to put up with? Seems like everyone with vapor lock problems want to deal with it by trying every trick in the book except the one that designers gave us for free. I learned of the problem back in 68 when my Charger R/T never vapor locked while my Brother's 383 car did. When we did our research we realized the problem and found a wrecked Hemi Charger in a junk yard. Swapped in the 3/8 sender, lines and separator and the problem never arose again. We decided the fuel was boiling in the fuel pump from the engine heat and reasoned that was why the factory gurus mounted the
It was OE on most Mopar V8's from around 1978 till EFI came around... They saw the positive value in eliminating Vapor Lock which was getting to be more of an issue with stuffing more stuff under the hood & running hotter to reduce emissions...

The filter has a 5/16" inlet & outlet plus a 1/4" return line to the fuel tank...

A 68 440 R/T should have a 5/16" fuel supply line, In 69 I've seen 5/16" and 3/8" by 70 3/8" is standard with a 440... But whether the supply like is 5/16" or 3/8" after the fuel pump they all including 70 & up use 5/16" so the new filter works & solves vapor lock issues...
When I purchased this car it has a new looking fuel pump. With this fuel issue I have do I need to be looking at replacing the fuel pump also? I’m running an edlebrock 800cfm
carb and haven’t been able to drive this car in the heat sitting in traffic as it wants to stall or does stall. I don’t have this problem with my 70 300 very with 440+6 engine but there is a lot more room under the hood.
 
Considering most new parts are all made in China these days I tend to re-use as many old serviceable parts as I can....

That said new doesn't mean it's good... But then again lots of pumps get replaced when the true culprit is something else entirely.... If you decide to pull the pump put the pushrod too, it should be 3.22" long I've seen them less than 3"... But again the quality of new ones is poor at best so if it ain't broke don't fix it & if it is bad your best bet is to source an old original part that measures the proper number..

And realize and rubber hoses like the one at the sending unit should get replaced since this concoction they sell as modern fuel attacks old neoprene rubber hoses & if the hose isn't leaking that doesn't mean it's not sucking air....
 
Considering most new parts are all made in China these days I tend to re-use as many old serviceable parts as I can....

That said new doesn't mean it's good... But then again lots of pumps get replaced when the true culprit is something else entirely.... If you decide to pull the pump put the pushrod too, it should be 3.22" long I've seen them less than 3"... But again the quality of new ones is poor at best so if it ain't broke don't fix it & if it is bad your best bet is to source an old original part that measures the proper number..

And realize and rubber hoses like the one at the sending unit should get replaced since this concoction they sell as modern fuel attacks old neoprene rubber hoses & if the hose isn't leaking that doesn't mean it's not sucking air....
Thank you for the info. I ordered new fuel and vapor lines in stainless. Also purchased new hose. I think I may purchase Edelbrock wood spacer. I want to fix this problem and not worry about driving the car when it’s hot out.
 
I wanted to ask one quick question on the WIX filter, I actually looked at my two repro Vapor Separators I have saved for a rainy day any they both mount vertically on the block. So, if I just use the WIX 33040 instead of the OEM style, I still want to have it oriented vertically as well? The OEM repros seem to have something rattling inside of them -- not sure if that is correct or a bad thing so I figured I'd just try the WIX for now.
 
The Wix has the return line entering from the side, I try to get the side nipple higher that the nipple feeding the carb......
 
The Wix has the return line entering from the side, I try to get the side nipple higher that the nipple feeding the carb......
Thanks! In the pic here, it looks like it's going up, not on the side. Just wondering if I need to mount it vertically. Wrong image on AZ?
Amazon product ASIN B000C9UJAA
 
Looks like they changed the design... Which is actually a good thing... The key thing is having the return however it is designed internally to be the highest fitting so air always goes through that fitting... A few minutes of testing should make the design pretty apparent....
 
Looks like they changed the design... Which is actually a good thing... The key thing is having the return however it is designed internally to be the highest fitting so air always goes through that fitting... A few minutes of testing should make the design pretty apparent....
Check! Thanks! Got the return line recently. Fun project coming my way!
 
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