Convert progressive 2x4 linkage to one to one.

[HTM101]

Doug & Stangman,
The splined shaft came from Good Vibrations Motorsports.  The shaft coupler with 2 set screws, is a McMaster-Carr item. 

The black plastic piece on the front carb is a throttle position sensor.  I used it with an Innovate Motorsports 2-channel wide band O2 system for tuning.  Got some very good data from the system which helped me dial-in the pair of QFT's. 

David

[My427stang]

A couple of comments late in the game

1 - I agree completely with the "no carb is too big" rule as said earlier and referenced to Vizard.  If you can transition from idle to main circuit, often a bigger carb is easier as is less likely to go fast on top from too much signal.  The engine only pulls what it pulls and if there is airflow over the booster adequate to keep a good fuel curve, too much isn't bad

2 - I cannot imagine any reason that 1:1 wouldn't behave.  Of course if you have a trigger-quick throttle, or you are designing a car that grandma might put to the boards entering traffic, it could have a bit more response than desired, but tunnel rams and cross rams do it all the time and I haven't seen them do that.  I have zero experience in the development of 1960s Fords, I was born in the late 60s, but I could see the benefit of not having to precisely tune a progressive system.  As long as the primaries are in the ballpark at idle compared to each other, the only real synchronization is the balance tube to the vacuum secondaries.  That makes it a lot easier on the line or in small-town Ford garages

[Falcon67]

For those with interest - Spline shaft, et al - E-55-101, E-55-107
http://www.goodvibesracing.com/Enderle_Linkage_Kits.htm#COMPONENTS

I'll have to grab a set of those, I can make a tie bushing.

I look at 2x4s like this - with vacuum secondaries, the back half of the carbs will only come in when there is sufficient air flow.  They don't count for anything until well up in RPM.  On a dual plane intake, the engine sees half the current venturi area.  A tunnel ram with two 600s on it can also be looked at as two 4 cylinder engines each with a 4 bbl carb.  Only half of that carb is in use most of the time.  Would you put a 300 CFM 2bbl on a 4 cylinder?  No problem with that.  Also, even on my 302 I've run a 600 DP as a street/strip carb.  So at worst, slamming the throttle open on two 4s is about the same as a 600 DP.  If you can tune a 600 DP to leave on cue, then you're good.  One of the reason's the Eds work a little better out of the box than maybe the 1850s is that the primary boosters are more efficient and the front venturis are smaller.  Maybe more like a "500 DP".  I would think a pair of the Thunder AVS units with tuneable secondary air vane tip-in would work pretty well.

[Tobbemek]

Prosev-----porgesiv----- progg--? how do you spell that???

[Falcon67]

LOL