the carb is a 4150 (I think 600CFM)it's a basic perormance replacement for a smallblock V8.
the biggest thing was to lock the secondaries to open
mechanically.But this made me really lean when I steped on it,so on went the 50cc(stock is 30cc)accelerator pump.This got me back to correct mix when I punched it;this is where all the poular 2 barrel carbs for
rotary's fall short...They can't supply the fuel when you stomp the gas at 1500 or 2000 rpm,a holley pumps fuel
(in my case 50cc's or a double pumper 60cc)as soon as you open the throttle.I'm not saying that they're superior because holley has the opposite drawback,
they could never flow as much as a down draft.Anyway
holleys can be worked with,it just takes patience and understanding of what each part does to
see what needs to be changed to make it run right.


Nick

 

Cool, but I'm not that impressed. IMSA cars back in 1980 ran bp 12As with the modded Nikkis to make just as much power, and with only a few changes to the carb. Racing Beat claimed 235hp SAE with just primary venturies bored to .980", 160 primary fuel jets, and 190 secondary fuel jets.

 

some people are never impressed unless you show them a 1000hp car with a naked chick inside. That and a Holley carb can be rebuilt and rejetted much faster than the Nikkis and parts are abundant, and cheap too.

 

The whole secret to running a Holley on a ported rotary is tuning the accel. pump squirter. The ones on the stock Holley's are huge, and if you try to tune the carb with the stock squirter in there it will never work right. Think VERY small when you start, and work up from there.

BTW, I had a half-bridge 12a in my 85 that pulled perfectly off the line, no stumbles, and would go around corners with ease.

 

funny you mention that my holley came with a 31 nozzle I changed it a few times I tried a 28, 25, and a 21. Yesterday I reviewed the holley performance manual this is what I learned: a smaller nozzle will give a smaller shot over a longer period of time a bigger nozzle gives a bigger initial shot but without the duration. Holley recomends using a bigger nozzle for cars with a good power to weight ratio(like our 7's) So this morning my crazy *** went outside and slapped a big 'ol 37 on that mojo and I seem to have better throttle response (no more stumble) but it still leans out at 6000rpm at WOT. Maybe a bigger accel pump? I'll try it later.

 

I have a holley 600 on my car... 74 4 port 13b with a street port... works fine on mine... I would go a bit smaller on a stock port motor... or even better yet bridge port it

 

nope samller nozzle is the way to go I changed the pump cam position to #1 and changed the accel pump I don't know what size but I think its bigger. Better but still cuts out at 6000rpm