hi,

i want to know how compadible the internals of a 20b and a s5 n/a motor is? because my friend and i are eventualy going to build up his 86 base into a street monster. scoff all you want at base 4lugers but we dont care so nether should you. he is currently out of town and i was just brain storming about ideas to my self while doing the laundy. i was wondering if i could use 20b 3 rotor e-shaft, and engine dowls with 13b housings, iorns, and s5 rotors. And on top of that have all the housings street ported and the exhaust ports ported. i know that the rotating mass would have to be ballenced and what not as well. We would prolly make our own intake manifold and exhaust manifold, use the mechaical oil pump from the s4 if we can, megasqurit standalone, prolly 20b fuel rails, denso 460cc injectors, and obvously fabricate engine mounts. thats all i can think of off the top of my head, but right now its just theroetical. I also dont know too much about carburated rotarys, would it be easyer to carburate this kindof motor? I know this is fraken-motor but we want to keep things as simple and easy to work on as possible, so i'll listin to any valid ideas. thank you.

 

What the heck are you trying to do?

The S5 NA rotors will be fine on the 20B as they weight the same as the 20BREW/13BREW rotors. The housings will work as well, but the emissions passages will not line up (obviously not a concern for an engine like this).

If you are trying to make your own 20B, you will need the expensive and hard to find 20B thick front-center iron to make it work. You'll also need the front tension bolts, front iron and all associate miscellaneous that goes with it.

The best bet if you are trying to make a 20B NA is to actually start with a 20B short block and swap the S5 NA rotors into it. Then work out your manifolds and header.

 

yeah prepare ur self to spend some money

 

how much do you guys think it would be to have a 3 rotor e-shaft made so that you can peace together 2 13bs(one front, 3 iorns, 2 middle, and one back)?

 

If you don't know anything about carburetors, then stick with fuel injection.

Simple? I don't think you could have made it much more difficult, lol. You can simply buy a used 20B-REW with 2 turbochargers for about $3500.

Precision Engineering makes one, as well as a modified center iron. I haven't seen any recent pricing, but it's probably about $3,000.

 

well simple as in trouble shooting if somthing goes wrong after we do it, i know how a carb works just not on a rotary, does it open in stages like what the injectors do? i've looked at one on my friends 12a 1st gen and to me it look werid. we have no shortage of s4 n/a parts because not counting the car they is the golden child we have a 86' base auto (did they ever make a manual sun roof for the rx7? cuz this one has one and i was wondering if the kid we bought it from destroyed a non-sunroof car.), a 86' base w/o storage pods or back seats (werid i know, and yes its OEM, there is no holes in the carpet were the pod should be and the fiber glass section that there supposed to fit into has no holes ether), 86' LX 2+2 i think (same as base just back seats and PS), and a 90 GTU. our golden kids are my 87' black TII and his 86' blue N/A w/ alu non turbo hood. so we have 6 fc's together.