Plan on doing a pineapple large street port on a spare S5 engine block with 73k miles on it. Car ran great no leaks on side seals, question is... DO I need to rebuild the engine while im doing my street port and intake/exhaust porting and if so what seals do I need to replace at the bare minimum. Saving my rebuild experience for a 13bt or 13brew since the cost is ~1000-1500 giving parts. Would I be ok to just reassemble after done w/ porting?

 

there is no simple answer. i guess it pretty much comes down to what your goal is. old seals can be used, but they MUST be spec'd. get acquainted with the factory manual!

i can only speak for myself, so here goes ... if i were you, maybe i'd try using the viton seals wherever i can, since they are purported to reusable. i say this with the assumption that you're just experimenting and testing your skills, so you may have to tear it back down a few times as you learn. also, i had an experience many, many years ago that left me pondering how used is too used when it comes to springs for the various seals? so you may want to research that and see what you think will work for you in that regard. other than that, as i said seals are reusable if they spec out.

 

since the engine will be apart, i would measure the seals, if they are within specs, then you're fine with reusing them, if they are not you should replace.

its also nice to upgrade to FD corner seal springs, and you will need new corner seal plugs.

chances are with 73K if it was running fine before you took it apart, you will probably only need side seals.

remember the rotary has more seal length than a piston engine, AND more time for the seals to leak, due to the 270 strokes, so sealing the chamber is the #1 most important thing you can do.

 

Sound info.. does ~800$ sound right for a refresh like replacing gaskets and specialty tools saw a list from this link https://www.rx7club.com/2nd-gen-archive-72/13b-rebuild-parts-lists-395019/ post #15

89-91 NA Gasket Kit http://atkinsrotary.com/store/custom...2&cat=0&page=1
2mm corner seal plug set (optional) http://atkinsrotary.com/store/custom...3&cat=0&page=1
FD corner seal spring set http://atkinsrotary.com/store/custom...4&cat=0&page=1
2mm side seal spring set http://atkinsrotary.com/store/custom...7&cat=0&page=1
Viton Oil Ring set http://atkinsrotary.com/store/custom...8&cat=0&page=2
Front main seal http://atkinsrotary.com/store/custom...2&cat=0&page=2
Rear main seal http://atkinsrotary.com/store/custom...3&cat=0&page=2
Thermal Pellet http://atkinsrotary.com/store/custom...1&cat=0&page=2


Hope that helps.

That + pineapple large street port on my spare s5 13b. Then possibly RB full exhaust. I still need to research porting the intake to match the exhaust mods. Anything else I should add while shes open? Engine ran very strong.

 

found an even better option... http://www.rotaryaviation.com/overhaul_kits.htm Would the BASIC KIT + RA Super seals be good enough for a running engine with low mileage?

 

rotary aviation seal have bin known to be extremelly hard on the housing ie. eating the chrome off very fast.

 

Can't stress enough!!!! Do not go cheap on rebuilding the engine. Any cut corners will almost always come back to bite you in the ***. We have ran ra super seals for years and years with excellent results. I highly recommend them.

 

thought only the FD housings or cosmo housings had the chrome coating. Could of sworn I read that some where.

 

I understand this fully. But the engine is low mileage and runs great. Was thinking more of a refresh than a rebuild while I had it open to to port/polish.

 

OK so I purchased a turbo II in this time frame and am now looking at either to still go with the large street port or... (since this wont be a DD, mostly a weekend warrior/track hoe) Is the 6 port worth going full bridge, exhaust to compliment it and 51 IDA w/ 46mm chokes on mazdatrix carb intake? Or will I still make more power and be happy w/ the low end of large street port fuel injected.

 

i want a bridge on my 12a! nd a street port on the turbo 2!

 

Yea next purchase will probably be a clean first gen.

 

just buy a atkins rebuild kit parts worked fine in my 20b and parts are well priced aswell