Carb Question
 

Hi guys,

I'm new to the RX7 scene and bought a good condition '85 GS roller, and my cousin donated a 13B 6 port engine from an '85 GSL-SE. I also have access to either a Holley 600 (which I see a lot of hesitation about) or a stock Nikki carb from a 12B.

If I go with the Holley, it looks like I'd need to get the intake Manifold from RB for $300.
If I go with the Nikki, what intake manifold would I need to get? I haven't been able to find one online yet.

One other factor, if I went with the Holley, I know a guy on our racing team that is a genius at carbs and would be able to fine-tune the Holley to work wonderfully. On the other hand, I know the Nikki is excellent on rotaries so it would make more sense to lean that direction.

Which would you choose, and what intake would I need to get a carb on a 13B hooked up?

Thanks!

The nikki is not really an option as, if memory serves, there are no readily available intakes to mate it to the six port motor, even if there were the nikki would not have enough cfm for the 13B.

You are left with two options, the holley will be best suited, IMO if your intended use for the car is on the street, its shortcoming is with hard cornering,(fuel starvation), so if you intend to autocross or do track days then the best setup would be the weber 48 IDA, a little less streetable, especially if you live where it is cold,( it has no choke) but it handles the curves much better. Racing Beat offers the manifold for either the Holley or the Weber, but not the nikki.

Thanks! A third option has popped up for me. I have access to an OER 45, which will suffice for now. I really like cornering fast so the Holley concerns me. Plus the intake is more expressive, so I think the side draft will work nicely. Eventually I can upgrade to a full weber, as finances allow. This car will be a good weather only, fun street car with limited track day outings.

That 45 will be hard to tune for the 13B, it barely has enough cfm for a 12A. But for starters it will get you
going.

The nikki could work but it will need to be hogged out so that it flows more fuel/air. Its a pretty fun
project but not recommended for a novice. A 12A intake can be made to work with the 13B by using
an 13B intake blank and creating a 12A to 13B converter plate. Seen it done before on a 4 port. Not sure
how to deal with 5/6 ports though.

Qingdao has done it, for a Nikki on a 6 port.