Hi guys, looking for a carb to suit my rx4 13b extended port, found a cheap modified nikki that was on a bridgeport, with the following information:

Both Primary and Secondary chokes have been enlarged
Primary and Secondary Jets have also been enlarged to suit.
Primaries 110 Secondaries 200
Mechanical Secondaries

Common sense tells me that it'd probably be too much carb for my streetport, but I was wondering if we're in "it could be a little bit better" or "it'll be completely undriveable" territory here. The jets have been drilled, but I have some spare nikki jets I could drill to a size smaller and drop in.... thoughts?

 

I dont see why you couldnt jet it down a bit for your application. A streetport motor would need at least a 600cfm carb (at least according to racing beat) I doubt even a modded nikki flows more than that...

 

I guess I'm worried that the larger barrels will make it too sluggish without the higher CFM of a bridgeport, more than anything. I don't think the venturis are easily swapped in and out either

 

It will work, but if you keep a carb on the small size, you will have more low-end torque

Carb size depends on what you want to achieve power-wise. Rotaries require 1.92 CFM (cubic feet per minute) to make one rear wheel hp
So a 600cfm carb will flow enough air to support 300hp

In my upcoming RX4 halfbridge setup, I have set the goal for 200rwhp. I am using dual DCD carbs (building my own version of the "rotary engineering" setup) that will flow 225CFM each, so 450 in total.
This means it supports up to 230rwhp.

Enough for my goals, and perfect for some good low end torque, especially with near original primaries

 

I think it can be made to work well. I'd try it as she is. Then maybe change jets. It won't be too much flow.