carbs for a Ford medium riser 2x4 intake

[jholmes217]

Picked up a 2x4 Fomoco 2x4 medium riser intake.  I can get a pair Holley 1850-2 600 cfm carbs for a good price.  What would be required to get these to work with this intake manifold?

[e philpott]

I have the 1850's on mine ..... secondary carb needs stud mounted in a lower hole for the progressive linkage to work and needs the base plate clearenced for the throttle linkage to bolt up ......

Both carbs need a vaccum balance fitting to connect both carbs so the secondary's open together ..... that's pretty much it

heres a link that gets more detailed
http://www.ford-trucks.com/forums/1004931-how-i-modded-regular-holleys-for-2x4-use.html

[jholmes217]

Thanks.  Reproduction BJ/BK carbs are out of my price range.  Holley 1850s are a dime a dozen on Craigsist.

[jholmes217]

What size jets did you use?

[e philpott]

I started with stock size 66's and ended up 68's on my 416

[jholmes217]

I started with stock size 66's and ended up 68's on my 416

Thanks.  My car is a 428, so I'll try starting with 68's.  Do your carbs have the stock metering plates in the secondaries, and did you go with light springs? 

[e philpott]

stock blocks and plates .... I went with the light spring in both

[jholmes217]

stock blocks and plates .... I went with the light spring in both

Thanks so much for the information.  There is a guy that has a pair of Holley 1850-2 carbs local for $100.  Sounds like I should jump on that, and do the modifications. 

The benefit of my 1969 Mach 1 being a Q code 428 Cobra Jet car is I don't have to worry about manifolds and carbs working with a shaker hood scoop.  A previous owner of my car also evidently switched hood scoop emblems when he went looking for a street race.  I found 351 emblems in the glove box!

[shady]

sneaky...I ran a boss 302 in a comet that I had put some 260 tags on it from a fairlane.

[Drew Pojedinec]

I haven't run them yet, but apparently this is what QF thinks:

[jholmes217]

I haven't run them yet, but apparently this is what QF thinks:

Good info Drew!  Thanks for posting!

[427LX]

I setup a pair of 1850's on my 427W recently and if you are working with used carbs make sure you check the primary and secondary carb body sealing areas for being flat. Most will have a sunken area in the middle and this can cause gasket sealing problems that can affect performance.
On my engine which is in the 550HP area,I ended up with 67 Primary jet and 68 jets in a jet plate setup.
Also don't be afraid to try a 8.5 PV during your tuning as this helped bring the extra fuel in a bit earlier during heavy accel without secondary opening.

[jholmes217]

If running a distributor with vacuum advance, should I put a cap on it, run it to the front carb, or run it to the back carb (closest to firewall)?

[e philpott]

front carb if your using progressive linkage