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Correct fuel pump for ‘68 Coronet R/T?

piver

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Well, losing my mind on this one. Lol. Have a cheap electric fuel pump that came with my ‘68 Coronet R/T. Want to buy a mechanical to go back to original. Can’t find a correct one to buy - anyone know where to look? FSM calls for Carter MS-4434S, but the 4434 at Summit et al. have a 5/16” Inlet. I have 3/8” Fuel Lines. Should be 3/8” Inlet and a big enough Outlet, with 7 1/2 psi max. Help :)
 
I used the one specified by Oreillys with the 5/16" fuel inlet line on my '68 R/T, works great. Don't forget the Vapor separator and the 1/4" return line.
 
Be careful with the 7.5psi if you're using a Carter/Edelbrock carb. I think those require 4-5.5
 
i think rock auto has them. they're a higher pressure pump than the 383/lopo 440 pump and need the vapor separator. factory was a 5/16" inlet and outlet. a carter 6903 would probably solve your line size issues but won't like a vapor seperator without some mods to the pump or separator.
 
if I remember correctly, 68 440 cars came with a 5/16 inch fuel line.
I'm beginning to believe that...others say this, the correct pumps are 5/16", Mopar Parts Catalog suggests 5/16" etc. Thing is, my R/T has 3/8" installed already.
 
I used the one specified by Oreillys with the 5/16" fuel inlet line on my '68 R/T, works great. Don't forget the Vapor separator and the 1/4" return line.
Do '68 Coronet R/T (4BBL 440 HP) necessarily come with the Fuel Vapor Separator? Mine doesn't have one, unless it was taken off for some reason...which would be weird, as there's no Return Line etc.
 
i think rock auto has them. they're a higher pressure pump than the 383/lopo 440 pump and need the vapor separator. factory was a 5/16" inlet and outlet. a carter 6903 would probably solve your line size issues but won't like a vapor seperator without some mods to the pump or separator.
My R/T doesn't have a Fuel Vapor Separator on it. Weird if it taken off, as no Return Line either. Wonder if it's necessary. Hope my re-cored radiator and shroud make it uneeded.
 
Thanks all for your feedback on this. Super confusing to me. But, it seems everyone agrees I should have 5/16" Lines, but my car has 3/8". Maybe it was previously modified? Anyway, despite FSM calling for a Carter MS-4434S Fuel Pump (5/16"), I went with Carter M-4845 from Summit - 3/8" Outlet and 1/8" Inlet, 6.8-8psi. Arrives later this week, so will try it and hope it works. I don't see a Fuel Vapor Separator on the car now, so passing on getting that unless it vapor locks.
 
My 68 R/T doesn't have a return line, nor a vapor separator. It just has a normal filter on the output of the fuel pump. The majority of my cars are 66-68 and none were equipped with return lines. I can't speak about a 69 as I don't own one. 1970 has a return line and a vapor separator. The pump I listed in my previous post will work for you as you already have a 3/8" line.
 
My '68 R/T came with the return line. It is an early St. Louis car. This is before I changed the fuel pump, but it shows the vapor seperator and the return line. The chrome fuel pump didn't work for very long long. The last picture shows the Oreillys fuel pump that I put in recently. I was hung up on the 3/8" line, but 5/16" is adequate, obviously.

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Baby Blue, my unrestored '68 GTX, 440 automatic, came new with a vapor separator and return line. Car was a December Lynch Road build. My stock numbers matching Hemi GTX was restored with the return line, but no vapor separator, same with my fifth GTX, a '69 numbers matching 440, late build St. Louis car. Both the Hemi and the 440 car performed better after I installed a factory vapor separator.
 
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My 68 GTX was a early Dec. 67 build car. It didn't have the dash reverse light, was originally an inland shifter. It also had a 5/16" fuel line with the 1/4" return line. As has been mentioned above, if you already have a 3/8" line then just use the pump that will fit a 3/8" line.
 
My 68 Coronet R/T was built in Sept 67 in St Louis... Originally a 5/16 line and no return... Being restored with a 3/8 line and a return since someone bought them then threw in the towel on restoring a 70 Coronet R/T& I got them cheap...
 
My car has SPD of 9/29/67 St. Louis. 1Wild R/T, Sounds like our cars are "close brothers".
 
Thanks all for your feedback on this. Super confusing to me. But, it seems everyone agrees I should have 5/16" Lines, but my car has 3/8". Maybe it was previously modified? Anyway, despite FSM calling for a Carter MS-4434S Fuel Pump (5/16"), I went with Carter M-4845 from Summit - 3/8" Outlet and 1/8" Inlet, 6.8-8psi. Arrives later this week, so will try it and hope it works. I don't see a Fuel Vapor Separator on the car now, so passing on getting that unless it vapor locks.
My 1968 Charger R/T came from the factory with the 3/8" fuel line and 1/4" return. From what I remember, only the Hemi and 440 4 speed cars got the larger fuel line for what I believe was to control the vapor locking issue. 440 and 383 Automatics got the 5/16" line with no return. If your car has no return line, it came with the 5/16 line so someone must have upgraded it. Included with the 3/8 line upgrade, the send unit would have had a 3/8" outlet and 1/4" return nipple and the separator mounted on the fuel pump bolt. From what I recall, the separator had a 5/16" inlet and outlet along with the 1/4" restricted nipple for the return line. My 70 440 Six Pack engine got the same set-up. I don't have any pictures of my 68 set-up but here is a picture of my 70 Six Pack engine showing the fuel pump with 5/16" tube feeding the separator. That said, I suspect the fuel pump more than likely came with a 3/8 inlet provision and 5/16 outlet but I have no proof of it. Just speculation. I don't remember the Carter number on my 6 pack engine but it has the 3/8" inlet provision so you can use either the 3/8" or 5/16" adapter. Hope it helps.

440 Six pack-2.jpg
 
440 and 383 Automatics got the 5/16" line with no return
Not in all cases. My 4-23-68 SPD automatic R/T came with 5/16 fuel line, vapor return, and 3/8 sender w/return. The original lines still had the factory undercoating, but I replaced it with 3/8 to match the sender, which wasn't done originally.
 
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