WHYDTYTT: What Have You Done To Your Truck Today?

[85lebaront2]

I've asked permission from the owner to cut open the plastic bag that the adapter is in, but to this point I don't have it. But, it looks like the VV I have will fit, and it does so will a 2150.

The owner said it will be okay!

Not only will the VV fit, but probably large base Carter BBD, Stromberg WWC and Rochester 2G series from looking at the inner set of threaded holes.

[Gary Lewis]

Not only will the VV fit, but probably large base Carter BBD, Stromberg WWC and Rochester 2G series from looking at the inner set of threaded holes.

Eureka!

Here's a bottom shot of the VV bolted to the adapter.

The only potential problem, and its a minor one, is possible underlap where the adapter fits the base of the carb. I traced it in pencil, which is hard to see in this pic, but I've pointed out two spots to look at closely. I think a gasket would still seal, but the line is actually outside of where they fit up, and you can see into the gap.

But, a thin aluminum plate would seal it up, with gaskets top and bottom - if there is a vacuum leak,

[ArdWrknTrk]

Eureka!Here's a bottom shot of the VV bolted to the adapter. The only potential problem, and its a minor one, is possible underlap where the adapter fits the base of the carb. I traced it in pencil, which is hard to see in this pic, but I've pointed out two spots to look at closely. I think a gasket would still seal, but the line is actually outside of where they fit up, and you can see into the gap.But, a thin aluminum plate would seal it up, with gaskets top and bottom - if there is a vacuum leak,

That's why I use black marker and a scribe

 

On Tue, Aug 20, 2019, 3:53 PM Gary Lewis [via Bullnose Enthusiasts] <redacted_email_address> wrote:

 

 

 

[Gary Lewis]

I could use the marker just on the carb and the scribe wouldn't do any real damage.

I'm sure at one point we'll want to do that. Good idea.

[85lebaront2]

Eureka!

Here's a bottom shot of the VV bolted to the adapter.

The only potential problem, and its a minor one, is possible underlap where the adapter fits the base of the carb. I traced it in pencil, which is hard to see in this pic, but I've pointed out two spots to look at closely. I think a gasket would still seal, but the line is actually outside of where they fit up, and you can see into the gap.

But, a thin aluminum plate would seal it up, with gaskets top and bottom - if there is a vacuum leak,

Unless the plan is to use two non-feedback VV carbs (which setup correctly would probably run very well) I don't think it would be a problem, unless the Autolite/Motorcraft 2100 has a bunch of reliefs underneath also.

Holleys shouldn't be a problem, nor would any of the large base Carter, Stromberg or Rochester ones. The VV works like a 2 barrel downdraught (to use the Queen's English) Zenith-Stromberg CD carburettor, or if you prefer a Skinner Union.

[Gary Lewis]

Unless the plan is to use two non-feedback VV carbs (which setup correctly would probably run very well) I don't think it would be a problem, unless the Autolite/Motorcraft 2100 has a bunch of reliefs underneath also.

Holleys shouldn't be a problem, nor would any of the large base Carter, Stromberg or Rochester ones. The VV works like a 2 barrel downdraught (to use the Queen's English) Zenith-Stromberg CD carburettor, or if you prefer a Skinner Union.

I doubt VV's are in the offing, to borrow Brit parlance. But, I don't know that there is a plan. Getting the intake was Step 1.

Do you have any recommendations, Bill? I know you'll ask what cam, compression, etc and that's all up in the air as well.

Anyway, something that would be small enough for two of them to feed 300 cubes at low RPM.

[ArdWrknTrk]

I've asked permission from the owner to cut open the plastic bag that the adapter is in, but to this point I don't have it. But, it looks like the VV I have will fit, and it does so will a 2150.

The owner said it will be okay!

Aren't you and Matthew the ones who said (paraphrasing) "don't touch anything before or during a road trip"???

Hmmmmm?

[85lebaront2]

I doubt VV's are in the offing, to borrow Brit parlance. But, I don't know that there is a plan. Getting the intake was Step 1.

Do you have any recommendations, Bill? I know you'll ask what cam, compression, etc and that's all up in the air as well.

Anyway, something that would be small enough for two of them to feed 300 cubes at low RPM.

If you could find a couple of the 2150 carbs used on the 2.8L engines, I believe they had a less than 1" venturii, .98 or maybe even smaller would be good. The thing to remember is if the carb flows 230 CFM for example, then two of them flow 460 CFM. The old formula for best guess on carburetion is Displacement in cubic inches X max RPM X Volumetric efficiency / 3456 = CFM needed using that, 4500 RPM and 75% VE I get 293 CFM. That being said, my Shelby using the 292 ci displacement, 7500 max RPM and 85% VE should have had 539 cfm. Shelby put a 715 CFM carb on, I had 930 CFM with dual Holleys. Multiple carbs will do better than one big carb for throttle response.

[ArdWrknTrk]

If you could find a couple of the 2150 carbs used on the 2.8L engines, I believe they had a less than 1" venturii, .98 or maybe even smaller would be good. The thing to remember is if the carb flows 230 CFM for example, then two of them flow 460 CFM. The old formula for best guess on carburetion is Displacement in cubic inches X max RPM X Volumetric efficiency / 3456 = CFM needed using that, 4500 RPM and 75% VE I get 293 CFM. That being said, my Shelby using the 292 ci displacement, 7500 max RPM and 85% VE should have had 539 cfm. Shelby put a 715 CFM carb on, I had 930 CFM with dual Holleys. Multiple carbs will do better than one big carb for throttle response.

This is why I gave away the rather rare *new* 4160 435 cfm carb I had to a member of the CT FTE club for his 300.

He sold it shortly thereafter, due to a growing family, but said it was close to ideal.

[Gary Lewis]

If you could find a couple of the 2150 carbs used on the 2.8L engines, I believe they had a less than 1" venturii, .98 or maybe even smaller would be good. The thing to remember is if the carb flows 230 CFM for example, then two of them flow 460 CFM. The old formula for best guess on carburetion is Displacement in cubic inches X max RPM X Volumetric efficiency / 3456 = CFM needed using that, 4500 RPM and 75% VE I get 293 CFM. That being said, my Shelby using the 292 ci displacement, 7500 max RPM and 85% VE should have had 539 cfm. Shelby put a 715 CFM carb on, I had 930 CFM with dual Holleys. Multiple carbs will do better than one big carb for throttle response.

Jim - We aren't planning on installing it at the show. Maybe powder coat it, but not install.

Bill - I know you know it, but for the others: 2bbl and 4bbl carbs are rated at different levels of vacuum for CFM. The 1 and 2bbl carbs were rated at 3.0", and 4bbl's are rated at 1.5" of vacuum. So, to convert a 4bbl rating to a 2bbl, or for that matter a 1bbl, you multiply by 1.414.

So, to use 2bbl carbs to replace the 715 CFM 4bbl on Bill's Shelby you'd need several 2bbl carbs rated at a total of 1011 CFM.

Wikipedia says the smallest 2150 had a 1.08" venturi and flowed 287 CFM. Two of them would be 574 CFM, but that's only 406 CFM if it were a 4bbl, and that's a very little 4bbl.

Compare that to what I've read is the Carter YF's rating of 196 CFM. So two 2150's would have the capacity of three YF's. Sounds about right.