Carb'd lt4
GM did actually make one for a while. I have one at home. I am working in Vermont this week, but will get you the part number when I get home later this week.
I am fairly sure GMPP sells a LT4 carbed dual plane intake just like they do the LT1 one.
Thing is at least with the injected manifolds GM did not bother to redesign the actual ports in the intake, they just added material above them to seal to the taller port in the heads. If they did not bother to make the actual production car intake right I highly doubt when they had Edelbrock make the carbed one they would have paid extra to update the manifold ports.
The LT4 might be an actual good choice if going to say 7500rpms but the available dual plane carbed intakes to fit the LT1/LT4 heads are not going to support the rpms necessary to make the LT4 heads actually work well.
Point being skip the LT4 heads and if you really want to carb a LT1 either keep the rpms down where the dual plane GMPP will work or convert something.


