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Joined
Feb 20, 2020
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Location
North Georgia
My Car
1972 Mach 1 dark green
Is there any way to determine exactly which engine I have besides pulling the starter to see the casting numbers there?  My vin is for a H code 351C but I have an M code 4v intake dated '71 and 4* heads with larger ports dated late '70 so they would have been for a '71 as well.  I orrdered a fuel line, pump to carb for my H code but it does not match at all what is there now.  I do have a Holley 750 carb so the fuel line may gave been changed.  I need to figure this out before I order any more incorrect parts.

 
The number over the starter will not tell you the block you have. Both 2 bolt and 4 bolt blocks have the same number and yes there are other numbers for some special editions. Date code will be next to the part number on the block above starter. Here is a good link to understand the casting and part numbers. http://www.mustangtek.com/block/Block.html

 
Because "M" codes originally came with a Ford carburetor and you now have a Holley carburetor you likely won't find a good match, depending on which model of Holley you have it may be close or not. Some have the fuel inlet on the left (driver's side) and some are on the right, and there are different configurations on the fuel inlet lines and fittings. The Ford carburetor inlet was on the front, on both 2 barrel and 4 barrel carburetors. Your other choice would be the fuel line for a 351C 4V engine, it may come closer to fitting, as it won't be quite as long. With either one, though, you'll likely have to modify it, or just make your own.

The external block configurations are the same for "H" and "M" codes, the carburetors are pretty much centered on each engine, just the 4 barrel carburetor is a little longer and the fuel lines are shaped a little differently.

 
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I hate it when "someone" has messed with things and now you don't know exactly what's what. If it were me, I'd go back and fully ID and understand exactly what I have. You seem to have identified that you at least have the top end for an M code, heads and intake, but have you checked for the VIN on the back of the block, driver's side below the head (usually) to know if you have a complete engine or the original block, upgraded? 

As for fuel lines to carb, make your own if needed. You need either 5/16" or 3/8" (probably only 3/8th available) from your local auto parts store. A good bender and some patience. Here is a pic or two of what I did for my M code with a 670 Holley, connected by a dual feed chrome fitting. On mine, I used 3/8" copper lined steel tube about 3 feet long, with 3/8 NPT fittings if I remember. On the pump end, I had to make an adaptor fitting as the pump is made for a 5/16' factory line. I used a short piece of ethanol resistant (fuel injector) line as a vibration damper and easy connector with PROPPER FULE LINE CLAMPS!! Now, it may take you a couple of tries to get it right, so be prepared. You will also need to remove the PS pump as the line will go below it. Also you need at LEAST 1" gap between the block and the line. Hope this helps.

fuel line 2.JPG

fuel line1.JPG

fule line 4.JPG

fule line 5.JPG

bending tool.JPG

 
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I only ordered the new fuel line for a cleaner line, old one is fine and will just clean that up the best I can.  I am changing a few things but with others I am taking the  "if it ain't broke don't fix it" train of thought.  The old fuel line is just fine......

will try to find the vin on the block

s

 
I only ordered the new fuel line for a cleaner line, old one is fine and will just clean that up the best I can.  I am changing a few things but with others I am taking the  "if it ain't broke don't fix it" train of thought.  The old fuel line is just fine......

will try to find the vin on the block

s
Ok so what you're saying is a stock H code line doesn't fit to the Holley. Before I did the job properly on my car (when the original carb was replace with a Holley) a PO had just cut the steel line at the carb end, re-bent it and then used a piece rubber hose to a brass fitting on the Holley. NOT the way it should be done, but will get you by for now. If you go this route, please use correct clamps. I can't stress that enough. **Please note; this pic was taken shortly after I bought the car and before changes were made, but may help you for now**.

IMG_2845.JPG

 
Mine also has a piece of fuel hose connecting the hard line to the carb feed.   The bends on the fuel line currently in place are no where near the replacement I got from NPD (assuming they sent me the right one).   I just had to start to wonder being I have a different intake, different heads what engine I really do have if not the H code it came with.  This picture is also before, looks much cleaner now (I have been working on the engine bay for the past 2 weeks).

fuel line at carb.jpg

 
Yeah, that looks home made. While I could be wrong, I am pretty sure the fuel lines for a 2V or 4V  with factory carb are at least very similar. The basic lay-out will be the same, but the carb position for the 2V may be slightly different to the 4 V. Unfortunately, I don't know anyone with an H code I could look at and confirm that. However, here is a pic of a friends 4V M code factory fuel line to factory carb. May not be too much help other than this typical bend shape. On mine as stated (second pic), it was cut and bent to connect a rubber hose to the Holley.

Just trying to understand what you have and how to deal with it.

DSC00012.1.JPG

IMG_2874.1.JPG

 
Geoff

The two fuel lines are different as the fuel filter at the carburetors are located different. The 2V fuel line ends between the distributor and the carb when the 4V line is much more on the driver side. The original fuel filter of the 2V (Autolite 2100) carb is oriented straight forward while the 4V fuel filter (Autolite 4300) is 90 degree to the left and 45 degrees down.

At the end, the original routed 2V fuel line will fit better for the Holley fuel line.

Cheers Frank 

 
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Geoff

The two fuel lines are different as the fuel filter at the carburetors are located different. The 2V fuel line ends between the distributor and the carb when the 4V line is much more on the driver side. The original fuel filter of the 2V (Autolite 2100) carb is oriented straight forward while the 4V fuel filter (Autolite 4300) is 90 degree to the left and 45 degrees down.

At the end, the original routed 2V fuel line will fit better for the Holley fuel line.

Cheers Frank 
Thanks for clarifying that Frank. I was wrong then in my thinking. 

When I did own an H code, I didn't take any notice of the fuel line or take any pictures, but that was waaay back in 1981 and I don't know anyone with an H code around here.

Geoff.

 
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