Thank you matthewq4b! This is exactly the information I needed!

FuzzFace2, eventually my brother may follow your recommendations of freeing up the exhaust and other bits. Thank you for your input as well.

Quick question, will any regular adapter plate from say Summit Racing or Jegs be sufficient to adapt the 2100 to a stock intake manifold?

 

I don't know if there is one made to do that but again I have not gone looking for one.
As I said I cant see putting a bigger opening carb on a small opening of the intake.


Now with that said I know they make an adaptor to go from the MC 2100/2150/Holley 2300 v2 bolt pattern to the after market v4 intake manifolds that are out there.


I did find this for a 1v intake to a 2v carb but it is for a chevy carb so don't know if it would work on a ford.
https://www.summitracing.com/parts/trd-2041/overview/
Dave ----

 

You want Trans Dapt Pt #2044

https://www.summitracing.com/int/par...2044/overview/

Or Pt #2025 (universal)

https://www.summitracing.com/int/par...2025/overview/

 

They tested at the same HG as Holley, it is industry standard. 1BBL's and 2 BBLs are measured at 3.0HG vacuum. 4BBL's are measured at 1.5HG Vacuum

To find the 1BBL & 2BBL CFM in the same HG (1.5) as the 4BBL's
divide the 1bbl or 2bbl's CFM by 1.414

To find a 4bbl's CFM in the same HG (3.0) as the 1bbl or 2bbl
multiply the 4bbl's by 1.414

The reason for the difference is due to the presumed theoretical maximum attainable vacuum at under load at WOT. And that is what the CFM rating on a carb is the maximum theoretical flow at under load at WOT.


Theoretically an engine with a 1bbl or 2bbl would not see a manifold vacuum of more than 3.0 HG under load at WOT.
Alternatively theoretically an engine with a 4bbl would not see a manifold vacuum of more than 1.5HG under load at WOT.

So since the maximum theoretical vacuum under load at WOT is different between 1bbl's/2bbl's and 4bbl's the HG the maximum flow is measured at, is different also.

Yes of course this changes with engine displacement but I believe when these rules where made it was done with a fixed engine displacement. But they needed a standard to use a as guide and this is what was done.

As an FYI Holley engineers did the design of the 2100 and 4300 Autolite.
That is why there is so much commonality between them and Holley's.

 

Good link Gary did not see that post till after I made mine DOH

 

If it's possible Treacy, ride this thread out to gain as much info as possible.
The members who have responded are very knowledgable and their insight is priceless when it comes to our trucks.

 

You're definitely right about that WhatsAChevy!

Last night my brother ordered the 2100. The hard part was finding it with a 1.08 Venturi. Just typing in 2100 would bring up a bunch of them and usually they didn't have the Venturi size. So I figured out that 70s mustangs, torinos, and f100s with 302s had the 2100 with the 1.08 Venturi. So he ordered one and an adapter plate. He can't wait to get it in.

Before rebuild the his 300i had a blow/cracked piston #4, two cracks in cylinder wall #3, and camshaft lobe for #1 was worn round. The truck still drove if you could stand the screaming banshee metal on metal screeching noise from the engine + a terrible tap noise. The engine and trans leaked fluids like crazy.

We we are slowly getting back together. The flare side bed needs work too.

So I'll definitely be back for more wisdom!

 

Did you rebuild the engine stock or go with a different cam?

 

As another 'wisdom seeker', I also will be eagerly following this thread, planning to do my DSII conversion with my rebuilt Motorcraft 2100 / 1.08 in the Spring.

Thank you Matthew, for the lead regarding the adapter plate, although I was able to source same item with a more reasonable shipping rate to Canada. TD Carburetor Adapter 2V Carburetor to 1V Base | Northern Auto Parts

There may yet come the day when I will be in a position to share my own wisdom with others in this forum,
but for now I'm much grateful to the contributing members for their help any time that I have asked.

 

Just a stock rebuild. It's going to be my brother's DD. I also wasn't aware of any performance parts until now. I have a 302 EFI in my f150 and I know there is tons of performance parts for it.

 

Well welcome! Glad to see some other people on the same track as me.

My Ford wisdom is with suspension and body fabrication. Plus a ton of other odds and ends repairs. My YouTube channel The Minute Masters has all of my DIYs.

 

That wasn't a normal rebuild was it? With cracks in the cylinder you had to get another block correct?

 

Just a normal everyday rebuild. I had the build done by an engine machine shop. They bored out that cylinder and sleeved it. So it's the original block.

 

I am surprised they did that. It's usually very expensive to machine it and install a sleeve. It's usually cheaper to look around for another block that is not cracked.

 

Actually the cost to have the engine rebuild was very reasonable. $1600 start to finish. This included parts, labor, the sleeve job ($260), assembly, and the guy painted the block and oil pan Ford blue.