Reply to "4 x Weber 48 IDF (not IDA) conversion"

The carbs become restrictive, not necessarily the manifold.

48ida's are used because of the torque trade off.

427 Fords had a set of 58mm carbs made for them for racing.

Probably the solution (for me) is going to be to go to IR EFI on a Weber manifold with larger bores. 50mm minimum, 55mm possibley.

It would seem that the EFI, with the CPU of course, is more adaptable.

I shall find out.

Also, I personally never found the Webers feeling restrictive.

I ran them before on a big port/quench chamber 12.0:1 engine.
They were about as torqie as the 750dp Holley on an Edelbrock Torker. There are those who will argue that isn't saying much.
4,500rpm was the magic number for that engine set up to explode, power wise.

Power under that was ok. It just didn't pull like a 427 does. Actually I think a 428cj is the king down low anyway. I think it is noticably more powerful down low then the 7 is.

All that doesn't matter a hill of beans.
A freakin' diesel will out pull them all to that point, but who wants a diesel? Not me.

The Webers restricted or not are exceptional in the upper rpms.

I put 4 car lengths on a Paxton car at over 100mph. He was so small in my rearview mirror, I needed a telescope to see him.

I think everyone is too dyno crazzy. They can't explain why a car with an engine with 100hp less on the dyno kicks the crap out of the other car.

The answer is there is a lot more to it then just HP.
It's complicated.

Incidently. Why put a 427 small block in front of a ZF that has notariaty for not being able to handle a 427FE torque? Torque is torque.

If you use it you're going to break a very expensive item.

Sorry. Just my 2 cents worth. But you asked...well you sort of did anyway.