repuguru

I just don't think my"fantasy 20B" will be pushed to 650hp.

How do you think 2 Yaw Nikkis would look on a custom high riser? LOL!!!!!!

Well, I agree with Evil A. After looking at the facts it seems I can accomplish what I want by stripping the Jap spec turbo block rather than building one out of 13b parts+ that shaft from NZ. The compression difference is not large between the stock 20B rotors 9:0:1. Compared to the 74-78 13B 9:2:1.
I think I am going to start combing the adds looking for options for ignitions for a 20B.
Hey Jeff20b you think your ignition would work with this if I got the right parts from Racing Beat to convert the 81-85 ignition? It should work.
Does anyone know where you would want to combine the exhaust pulses from each exhaust port.

Jeff20B

iTrader: (13)

About the ignition, mine only works on a 2 rotor engine because both rotors fire at the same time and are phased 180º apart. A 20B's rotors are phased 120º apart so I'd recomend RB's 20B dizzy kit ($550 last time I checked) as a beginner's 20B ignition system. It's probably what I'm going to use; at least at first.

I'd imagine the exhaust pulses may need to be combined slightly differently than the rule of thumb for a 2 rotor engine. This means the short and long primary rules no longer apply. This is due to the 120º rotor phasing. The scavenging effect will most likely be different as you can imagine with pulses occuring every 120º instead of every 180º. I'm not sure if even Paul Yaw himself has done any of this sort of testing yet (are you familier with his 12A headers? Anyway...). Mazdatrix's 20B powered drag racer has 3 seperate pipes which snake out of the engine bay, but that is as much as I remember off the top of my head (I'm not sure about the mufflers and stuff). That is to say, I'm not sure where the pipes combind, if at all. Imagine that: three tail pipes under your REPU bumper LOL!!!!

I would imagine two Nikkis on a custom manifold would work well enough, if they've been jetted for a streetported engine (the 20B has quite large ports which mimic the size of a streetport). The only prob would be port velocity and the really sharp curve the AF mixture must flow through as it transistions from manifold to engine. You might also want to make half of one Nikki redundant or something (heh, a 6 barrel carb) but I don't know how it would run on only one primary and secondary. Or you could perform a work of art and somehow manage to run all 8 barrels into all 6 ports. Hmm, that would require a manifold that gets away from the standard seperate runner design that the Nikki was specificly set up from the factory to run. Probably not a good idea because it kills low end power. Just ask peejay.

repuguru

I'd do a plenum if I were to try to mix the two carbs together. Provided I went that route at all. After all was said and done Injection would be the best way to do this.
3 pipes would look funny coming out from under the bumper.