Hello everyone...
I just bought two 13B S4 NA engines, one is a flood water victim and one that was not able to run anymore and the owner of the FC just transplanted a Toyota engine instead.
Got the flooded engine for just $90
The second one that is just full of carbon buildup is for $180 dollars only

Upon tearing down the 1st 13B....looks like all is trash except one rotor housing and 2 rotors which can still be reused but needs blasting

Tearing down the second 13B...looks good...and the seals springs are weak due to carbon deposits and the corner seal springs are not working anymore...looks like due to carbon build up also or the inherent weakness of the design of the corner seal spring of the FC 13B. And also some unequal wear of the apex seals and rotor housings..but looks rebuildable to play with

Here are my plans in extracting max power in a stock intake manifold set up(No ITB's..maybe in the future )..please comment if you agree
I want to build this 13B S4 NA engine
Megasquirted
Still Non turbo
OMP delete and just premix
Simplified in every part possible
Still use the stock intake manifold as i dont have many funds to semi-pport or full peripheral port
Exhaust sleeve ...just to remove the wing noise diffuser
Exhaust sleeve...close the holes for the EGR on the exhaust sleeve...TIG weld a stainless sheet metal then port smooth it
Delete emission controls
Retain 5/6 port control...but using an airpump or still exhaust activation
Custom exhaust manifold
Street port the iron housings or bridge port?

In the Lower Intake Manifold I removed the ACV/EGR passages to simplify it and lower its weight, also the Oil injector ports...all the hose I will just shut close by TIG welding

 

From what Ive gathered the best stock intake combination for the NA would be the S5 upper/mid mated to an S4 lower. It's arguably not worth the labor (ask me how I know). A lot of grinding and squeezing bits around. But the S5 manifold is a very nice upgrade with the VDI hooked up properly.

 

Why? why not worth the labor?

Thanks for the reply

 

Plenty of things that must be modified, bent, removed, grind down, etc in order to gain clearance for everything. Certain parts must be replaced outright with S5 (fuel rail, rats nest) or require additional steps in order to work. It's a long-winded project, I'd hardly recommend it unless you are really motivated, but it mostly costs time and patience and the payoff is arguably worth it.

 

Any write up on this? I might give some time...I really want to play with this NA rotary engine. I dont know yet where I will install the engine. I have an extra FD chassis i bought from Japan. Thanks