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1969 Mustang Summit M2008 Series Carburetor Install ...

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I had started a thread asking about repro O.E. ford 4BBL Throttle Cable Brackets, which started to morph into a thread about modding one to mount on one of these Summit carbs.   Instead of continuing with that thread, I figured it would be best to start clean with a NEW thread on all that needs to be done to install this series of carburetors on a 1969 or 1970 Mustang / Cougar.

I'm installing the 600 CFM Vacuum Secondary version (M08600VS) on my 1969 mustang with 351W and Offenhauser 360Deg Equa-Flow Dual Plane Intake.   I'd guess the installation would be very similar on any 1969-70 Ford V8 that uses a square hole throttle cable & bracket that mounts to the rear carb studs.

FIRST STEP ... Modding an O.E. Ford or reproduction 4BBL Throttle Cable Bracket to fit the back end of this carb.   

In my case, I bought the Clear Zinc Plated '69-70 Boss 302 bracket from NPD (9741-6A).   The  '69-70 302,351 & 390 with 4BBL (NPD 9741-5A) could also be used, but I bought the Boss one because they sell for the same price and it was plated and the other one appears to be bare steel, plus I was hoping maybe it had a little more "drop" in the section that goes under the rear of the carb.

Well, the Boss 302 bracket only has 1/4" of drop to it and the Summit carb needs at least 11/16" so it needed to be modded to fit.

The 12/26/20 post in the original thread has pics of how I planned to mod the bracket: '69-70 O.E. 4BBL Carb Accelerator Cable Brackets ... - 1969-70 Technical Forum - 69stang.com and 1969stang.com The 1969 and 1970 Mustang Supersite


I cut a 0.83" wide strip of steel out of a RACO 2-Gang Electrical Switch Cover using a 6" Drill Master Cut-Off Saw I bought from Harbor Freight.   Had to put the back stop at the further back position and remove the clamp assembly as the cover was maybe an 1/8" too wide and just held it down by hand.   Had to flip over to finish the cut, as it only went about 80-90% thru.   A larger abrasive chop saw would be able to do in one cut or could also use a band saw.   

I used an old Holley carb base I had in my carb parts box as a "weld fixture", used a Ryobi 18V 3" cut-Off Saw to cut away the center section after welding the outside welds, then welded the inners after the piece was removed.   A little grinding to clean up my welds then removed from fixture.   

Cleaned it up with Lacquer Thinner then Wax & Grease Remover and then masked off the ends and painted the center section with cold galvanize paint.

Mod is pretty much unseen as mounted in the last pic.

I'll post other steps for this carb installation as new posts.     











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On 12/31/2020 at 10:45 AM, Mach1 Driver said:

I like you're use of the electrical box cover ;)

Gotta use what you've got laying around ... it being the perfect width and depth needed plus as a bonus already galvanized !!   

Was a little concerned that it was thinner steel than the bracket was made out of (0.068" vs 0.101"), plus the section of the bracket that I removed was ribbed but once finished it is stiff enough for the purpose.   Where the stiffness of the thicker steel and ribbed areas matter in this throttle cable bracket is at the cable mount & the tab that the spring attaches to, which my mod does not have any effect on.

Another thing is the new RACO brand box covers are formed differently than the old ones ... there is now a bit of a lip around the outside edge where the old one was straight.   The new style cover is made out of the same steel thickness and definitely makes for a nicer looking electrical box cover ... the lip that this new style cover would leave on each end of the steel strip could easily be flattened out before welding.   Just thought this fact should be mentioned if anyone is planning on duplicating this mod, see comparison pic below.




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The chrome fuel line that came with the Summit Carb has too long of drops at the carb inlets so it would be up against the stock heater hose routing to the intake fitting (as you can see in the 2ND PIC).   Also read a few reviews on the Summit site stating this tube was pretty cheaply made, so I did not want to try and modify it to better fit and have it end up leaking.   That and I always try for a mostly stock look, so I avoid CHROME as much as I can.

So I bought ...

(2) 20" lengths of 3/8" Ni-Copp Copper-Nickel tubing ** 

(1) Edelmann 130666, 3/8" Inverted Flare 5/8-18 Brass Tee 

(2) Edelmann 121006, 3/8" 5/8-18 Steel Tube Nuts (ended up with 1 spare)

(1) WIX 33032, 5/16" 20 Micron Inline Fuel Filter

These last 4 items are for pressure testing tube assy with air pressure in a bucket of water prior to final installation:

(2) Edelmann 123600, 3/8" 5/8-18 Brass Unions

(2) Edelman 120600, 3/8" 5/8-18 Inverted Flare Plug

** Really only needed ONE length of tubing, but my my 1st attempt did not go the way I wanted it to go, so once the smoke cleared I had a 12" piece of tubing and one tube nut left over.   So if you get only ONE length of tubing, you will need 3 extra nuts (121006 or equiv.).

I had ordered Edelmann Hose Barb to Male Inverted Flare Swivel Inlet Elbows 822550 (5/16-5/16") & 822660 (3/8-3/8") as well as a reducer for the 5/16" size (258560) in case I could not get the 5/16" fuel line to sneak over the 3/8" hose stem.   

However, they had not arrived yet so being impatient I instead successfully made a 3/8" bent tube elbow (95-100 Deg bend) as you see in the pictures.   I really thought this would be too long of a 90Deg drop putting me into the side of the distributor and is why I ordered the 90Deg fittings.   But as you can see from the pics, not only was I able to sneak the 5/16" hose over my slight bubble flare on the end of my custom 3/8" tube elbow, it also made the WIX filter fit between the carb & distributor near perfect.

Oh and the Fuel Pump to Carb Fuel line is a stock replacement for 1969 351W 4BBL, tweaked just a bit on the end to point in front of the carb.










Edited by stangs-R-me
Added a few more details.

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Here is a pic of the original Holley 5/16" custom fuel line I made years ago and the 3/8" version for the Summit Carb that did not go too well, including a kink in the short line to the front fuel bowl.   I think my final version in the previous post is much simpler and cleaner looking.   I also wanted the spark plug wires routed ABOVE the fuel line which I achieved as well.

I did not have a fuel filter on the Holley Install because it had the nice porous bronze filters in the fuel inlets.   The Summit Carb just has wire mesh screens in the inlets and the installation guide recommends an external fuel filter, so I found the WIX on NPD's site and was really glad I was able to make it look like it actually belongs there.






Summit-Carb-Inlet Fuel-Screens.JPG

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Final pics with air cleaner installed ... now I just need to wait for Spring (or unseasonably warm weekend between now and then) to start it up and see how it runs.

I do have the Electric Choke hooked up to the alternator Stator terminal, just as I did with the Holley.   Summit states 12V is mandatory (as I believe the Holley Choke Kit literature stated as well), but the choke on the Holley worked just fine on stator voltage.   I then removed both choke caps to compare and they appear to be IDENTICAL including the thickness & width of the flat choke coil spring.







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The rest of the Edelmann brass fittings arrived today so I thought I should post a picture of the two elbow options I was going to use.   As they shipped a lone 130666 TEE that arrived on Saturday separate from the rest of the order that arrived today, I was impatient and made my own bent 3/8" tube elbow as shown in the 01/05 post.

The fittings below would also work with the chrome fuel line assembly included with the Summit carb if you don't have clearance issues like I did with the heater hose.





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Something I failed to detail was the PCV connection.   This carb has a recommended 3/8" barb connection in the right front corner for PCV, however this is not an ideal spot for a typical Ford with a rear PCV connection.   If you have a carb spacer with the PCV port in it (typical O.E.M.), you are all set.   If you need to tap into the carb like I did, there is a rear port option.

The supplied brass hose barb can be seen installed in the last two pictures in the first post.





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Guess I should post an UPDATE since I've been driving it since the end of April !!

As I stated in my Jan 5th post, I pressure tested my custom fuel inlet line in a bucket of water with compressed air and had no leaks.   Well, I ended up having a fuel leak between my custom tube and the brass primary fuel bowl inlet fitting.   Tightening it did not help, so I removed the tube assy. and put on temporary hose barbs / tee and cobbled it together with hose & clamps.   My flare on the tube was good at the leak point, however the cone in the brass adapter was distorted / damaged so I ordered a 2-pc set of them from Summit (surprised it actually sealed up to the temporary brass hose barb adapter).   There was the Summit brand, Holley, & Demon to chose from and I went with the Demon 142117 2-pc. set as it came with the washers & screens and was the best value (all 3 are likely made by the same mfr.).   Replaced it and reinstalled my tube assembly and the leak was gone.

I had read that you really should use a 4-hole carb spacer on a dual plane intake so I also ordered up a Canton 85-154 4-hole 1/4" thick phenolic spacer and a MR G # 55 4-hole gasket for between the carb & spacer to replace the thick open center gasket supplied with the Summit carb.   Since my Offy 360 dual plane is not a 4-hole style, I used an open center gasket between the spacer & intake.   With my custom Ram-Air set up, I can't have any thicker spacer than this.

I had also ordered up the MR G # 97 1/4" thick heat dissipator set (2 aluminum plates & 3 # 55 gaskets) and tried this first but it did not dissipate the heat enough in that I could hear fuel gurgling when I shut the engine off when hot.   Funny, the Holley never did this and all I used under it for 30+ years was a single MR G # 55 gasket !!

The electric choke hooked up to the alternator stator terminal (instead of 12V as stated in the Summit instructions) also seems to be acceptable as the choke fully opens like it should and when it should. 

I also installed a Holley 20-59 Quick Change Cover Kit on the Vac-Secondary spring chamber.   The secondaries did not seem to be opening, so I swapped out the stock 0.033" wire spring for a 0.029" and they now seem to be opening at the right time.

I also followed the instructions from this video prior to installation:


I did need to turn the curb idle speed screw in a bit to get it to idle at 700-750 RPM and the sweet spot on the idle mixture screws is at 2 full turns out.   

My vacuum is a little low at idle (only 11-12"), and I'm tempted to swap the Holley back on to see where it was at before. 

It starts & idles nicely and runs & drives great, so I'm not too concerned at the moment.




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