Author Topic: Cross Boss carburetors  (Read 594 times)

Side-Oilers

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Re: Cross Boss carburetors
« Reply #15 on: June 15, 2022, 02:04:03 PM »
In my dreams I have a cross boss setup.  Perhaps a dual quad might be an interesting way to go on the Hertz.  I still find the Webers to be an attractive nuisance to me though I haven't a clue how to set it up or tune them.  So I stick with the single Holley 650 at present.
[/quote]


Richard, we all like to dream, but IMO having dual fours on a street-driven engine of your size and build is way overkill. It'd probably just use a ton more gas, and may be slower too. 

I've owned three cars with dual-fours ('57 T-Bird E-model, '60 Corvette, '66 Riviera GS)  and yes they do look ultra-bitchin. 
« Last Edit: June 15, 2022, 05:05:36 PM by Side-Oilers »
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TA Coupe

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Re: Cross Boss carburetors
« Reply #16 on: June 15, 2022, 04:54:49 PM »
To engage in some confirmation bias here, I saw that the early cross boss was actually an offset dual quad setup according to this YouTube with supporting photo of the early setup. 
https://www.youtube.com/watch?v=sD5FQCBfGEo
Therefore, I don't have to amend my story and it can stand as is (I got lucky).  Thankfully I did not mention the Autolite inline carburetor which would have thrown the proverbial monkey wrench back into the equation.  Whew!
[/quote

This page has pictures of and history about the prototype crossboss that my friend Gus Tarrrab bought from Smokey Yunick when we were there in 1988 for his first auction during Daytona speed week the same time that Tom McIntyre bought the "Mystery Motor "

https://www.inlinecarb.com/historical-info.html

        Roy

deathsled

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Re: Cross Boss carburetors
« Reply #17 on: June 15, 2022, 09:34:54 PM »
In my dreams I have a cross boss setup.  Perhaps a dual quad might be an interesting way to go on the Hertz.  I still find the Webers to be an attractive nuisance to me though I haven't a clue how to set it up or tune them.  So I stick with the single Holley 650 at present.
[/i]

Richard, we all like to dream, but IMO having dual fours on a street-driven engine of your size and build is way overkill. It'd probably just use a ton more gas, and may be slower too. 

I've owned three cars with dual-fours ('57 T-Bird E-model, '60 Corvette, '66 Riviera GS)  and yes they do look ultra-bitchin.
[/quote]
Thanks for your input, Van.  I will leave well enough alone.  I don't drive the car like a maniac.  Perhaps some day it will have a Weber setup but not today.  And not tomorrow.  I hope you are well.

Richard E.
"Low she sits on five spoke wheels
Small block eight so live she feels
There she's parked beside the curb
Engine revving to disturb
She's the princess from his past
Red paint gold stripes damned she's fast"

deathsled

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Re: Cross Boss carburetors
« Reply #18 on: June 15, 2022, 09:42:48 PM »
To engage in some confirmation bias here, I saw that the early cross boss was actually an offset dual quad setup according to this YouTube with supporting photo of the early setup. 
https://www.youtube.com/watch?v=sD5FQCBfGEo
Therefore, I don't have to amend my story and it can stand as is (I got lucky).  Thankfully I did not mention the Autolite inline carburetor which would have thrown the proverbial monkey wrench back into the equation.  Whew!
[/quote

This page has pictures of and history about the prototype crossboss that my friend Gus Tarrrab bought from Smokey Yunick when we were there in 1988 for his first auction during Daytona speed week the same time that Tom McIntyre bought the "Mystery Motor "

https://www.inlinecarb.com/historical-info.html

        Roy
Great photos and thank you for directing me there, Roy.  In theory, the character in my story could have the two carburetor setup on the Cross Boss.  The reality is that I erroneously had in mind the inline Autolite thinking it was two instead conjoined carburetors instead of one.  If I rerecord my story on my channel I lose all the hits I have so far the Road Closed horror story so I am leaving as is because technically, the character could have the rare and exotic manifold on his 69 Boss as apparently a few examples were made before switching to the inline configuration.  Besides it's all fiction in my story anyway, but I don't want to fall into the pitfalls of Hollywood that mislabels everything where technical matters are concerned.  I like to be more precise.
Regards,

Richard E.
"Low she sits on five spoke wheels
Small block eight so live she feels
There she's parked beside the curb
Engine revving to disturb
She's the princess from his past
Red paint gold stripes damned she's fast"

98SVT - was 06GT

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Re: Cross Boss carburetors
« Reply #19 on: June 16, 2022, 04:51:49 PM »
I've been kicking around getting a Dual Quad R code 427 Galaxie. I was chasing a 66 with drag race history but could never get a straight answer out of the guy as to how much of the car had been replaced during the restoration. The firewall had been hacked up to move the engine back and at one time it had a straight front axle under it.
Now I'm not sure if I really want a car that is going to eat $1 worth of gas each mile.
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deathsled

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Re: Cross Boss carburetors
« Reply #20 on: June 16, 2022, 07:24:38 PM »
It all depends on how far you drive it.
"Low she sits on five spoke wheels
Small block eight so live she feels
There she's parked beside the curb
Engine revving to disturb
She's the princess from his past
Red paint gold stripes damned she's fast"

shelbydoug

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Re: Cross Boss carburetors
« Reply #21 on: June 20, 2022, 09:24:55 AM »
A 2x4 Holley set up is similar to a Holley single "double pumper" set up but with vacuum "afterburners.

The FORD 2x4 linkage makes the primaries on the carbs open progressively just like a double pumper does.

The secondaries start to open around 3,000 rpm but open twice as fast as the primaries do in order for them to catch up and be synchronized at wide open throttle.

The vacuum secondaries do not really start to open until a little over 75% or so of the primary throttles.

So even on a 289, IF you can run a 4778, aka a 600dp, then you can run two 1850's.


Now in fact, those two 4's are actually cleaner then the single 600 dp by a long shot. They run 54 main jets and 119 secondary plates where as the double pumper starts at 69's with 71's in the secondary and will smart your eyes at idle because of the "competition" heavy idle. Set up that way to take advantage of the scavaging of competition headers.

The AFB dual four set ups are what you want to stay away from. Those have different linkage set ups and you tend to be running on the two of them all the time instead of the Ford set up of a primary and secondary carb.


If anything, you will find that the 465 Holleys are really too small for the set up.

Additionally, you will most likely wind up with a "Blue Thunder" version of the Ford "high rise" manifold. That manifold has the ports closed down near the intersection to the cylinder heads.

If you run it that way you will find that it is restrictive and unimpressive performance wise. You really need to port match the manifold to the head gaskets. Then you will see significant differences.


The neatest thing that I find is when the secondaries open you will hear this "whomp" sound like the sails opening on a racing boat does. The response is anything but a bog. The thing pulls big time.

The C6OA T/A manifold is a little bit of a different animal all together. On a dyno you MAY show that you are loosing HP off of idle but gaining around another 20hp over the ported "high riser". (Randy calls that one the "turd").

However take seriously the SA advertising that the "high riser" is good for another 55hp over the original single 4. I think that is conservative these days because of not necessarily being limited to the original camshaft profile.

The original single 4 is only good for around 12mpg cruising. If you beat on it, forget about that. Probably around 8mpg.


If you want to play "trans am racer", you will get what you will expect mpg and power wise, but that's up to you.

The 2x4 Holley set up is very streetable although I'm not sure some drivers are and there are some that have money to do this but are not capable of handling the car at all afterwards because of the additional power.

They do not pull like a Weber set up does. The power comes on in sudden stages. The Webers are just smooth all the way through.


Your biggest problem, if you want to call it that, is whether to run the carbs facing forward or backwards like the FE's do. Backwards has it's advantages and disadvantages but was proven to be a streetable linkage.

Forward was intended to be used on the T/A race cars and my thought is that it is there to simplify the linkage and save wasted time needless spent on a racecar.

Your choice. There is no right and wrong. It will just move the front carb 1/2" closer to the distributor cap and almost touch it. You feel confident that you will never develop a crack in that cap and short to the carb right?  ;)
« Last Edit: June 20, 2022, 09:27:22 AM by shelbydoug »
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crossboss

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Re: Cross Boss carburetors
« Reply #22 on: June 21, 2022, 03:46:10 PM »
Guys,
FWIW, the Inline is the carb. The Cross-Boss is the intake. Not 'Cross-Boss carburetors". Just making a correction as not to be confusing when describing them.
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