What's up rx7 lovers? I was wondering if I can get some advice for a 12a overhaul project. My main question is what parts will I need to get this job done right and get the most out of it. Lets say the rotors and housings are reusable along with the eccentric shaft . What would be the best parts to get together for a long lasting engine but at the same time get some performance (HP)

I have read stuff like using rx8 corner seals and springs or 93+ seals & springs. Can the guys with engine building experience and knowledge help a guy out? Any help will be greatly appreciated.

Signed,
The guy with an rx7 on jack stands.

 

3rd Gen corner springs, and Mazda OEM rebuild kit. Throw in a streetport as well, since it will be apart.

 

try this link http://www.mazdaspeeddevelopment.com...s/818512a.html

 

Thanks for the leads Jeezus and boyee, I aprecite the help. I'm suprised at the fact that not many people have posted furthur advise regarding my overhaul shoping list. So far I have one place where I can get the parts required for my build. however I would like to ask if anyone knows about an online store other than the one already listed by boyee where I would get the best pricing possible. If anyone from Orlando know a local shop even better. Again I ask for your help and or advise, before I buy the wrong stuff and get suckered by some jerk.

 

i have nothing but good to say about mazdatrix. decent pricing and fast shipping. www.mazdatrix.com . make sure you replace your rotor bearings and front and rear stationary bearings also!

 

try atkins. are you doing the work yourself ?

 

+1 for mazdatrix!
you can also find rebuild kits available at racing beat www.racingbeat.com
and also atkins rotary www.atkinsrotary.com
pineapple racing may have what you need too www.pineappleracing.com
also try your mazda dealerships or a rotary specialist mechanic because they should definitely be able to get you engine rebuild parts.
be on the lookout in the for sale section too. sometimes us members have extra engine parts laying around and sell them for a fair price.
to find local shops in your area its better to go to the regional sections and ask there because members who live in your area probably have gone to a rotary mechanic and will have either good or bad things to say. good luck!

 

Romelo I have a guy who did a few of my friends cars so, as far as I know he's acceptable. Boyee thanks for the links you rock bro.

 

So, RX-8 corner seals and springs? How are they different?

What about the apex seals, anyone tried non-oem apex seals (non-carbon)?

 

Is it worth to use the 93+ corner seals springs on street port 12a?

Will it really make a difference?

 

The flat-leaf corner springs are much less likely to fatigue & lose strength than the original wire springs.

 

plus they are a very cheap upgrade

 

Very nice I will include that in my parts list. What about solid corner seals from Atkins? Worth it or not?

 

I'm using the solid ones from Atkins. One advantage of them is you don't have to buy those rubber plug inserts (which tend to disappear once the engine is back together and running).

I recommend also using the green Mazda oil control o-rings. They are better than the Viton ones out there, IMO. Also, I tried the Atkins Viton ones, and found them to fit too tightly and broke a couple metal o-ring carriers. I've seen others have this problem, and some people that don't. The Mazda ones will fit perfectly and will last a long time. I also recommend OEM apex seals, but the Atkins ones will work too.

This is a break down of what I think:
- side seal springs (OEM)
- likely do not need new side seals
- apex seals and springs (OEM or Atkins)
- green OEM oil control o-rings
- new oil control carriers (can get away with used)
- new oil control carrier springs (OEM)..are also available in 'competition'
- soild corner seals
- '93+ corner seal springs
- rotor/main bearings, optional, depends on the condition yours are in. If yours are okay, keep the old ones
- soft seal kit (OEM)
- new t-stat and gasket
- FD oil pressure regulator (higher oil pressure)
- consider a nice streetport
- 17.5mm oil pump (you may already have depending on the year of the engine)

Other stuff to consider:
- pilot bearing, throwout bearing, clutch (might as well since you have easy access)
- front transmission seal (or front cover + seal)
- lightweight flywheel if that is something that you have been considering
- new belts, hoses
- new OMP lines
- rebuild OMP pump
- replace (or inspect) oil cooler lines, mounts, and oil cooler
- check radiator
- check waterpump
- general cleaning of engine bay
- clean/paint engine parts (housings, irons, waterpump, etc.).

 

I buy from Atkins, have had great customer service from them. 3rd gen corner seal springs, solid corner seals. That combo will give better sealing over time and ends up being cheaper than the the stock corner seals with the rubber inserts. Most of the engines I've torn down have been missing some of the rubber plugs, which lowers compression. The stock wire springs flatten out from normal heat cycling, the 3rd gen ones don't.

Stock steel apex seals are supposed to be the best and cause the least housing wear. The Atkins ones have worked fine for me.

For hp upgrades, exhaust/headers is first, then a modified Nikki or aftermarket carb. More than that, porting or forced induction. If you do port, make sure you have a good set of headers and full exhaust upgrade, otherwise your wasting your time porting.

 

i would probably suggest pulling the motor apart before ordering the parts.

most 12A engines i have pulled apart lately had scrap housings and there is maybe a dozen new sets left in the world fetching in some cases $800 per housing.

alternative would be trying to find a low mileage 1st gen in the wrecking yards and hope the money spent on the core engine isn't wasted.

13B/T/REW parts will be next on the chopping block.

 

This is the info I have been waiting for. Addict I like the list you made, mad easy to follow and understand. And Trochoid listed some facts that I've heard before regarding the stock apex seals. Ka rack I still haven't bought anything I think your right by waiting till we open her up and see what's the story.

 

Yep. Even if the housings are good, you can still save some cash by opening it up, clean/measure everything, and then order only what is really needed. It takes longer, but it can save some cash by not ordering some things that aren't really needed (bearings for example). If you open and find the housings to be toast, then you will know to start searching for 12A housings or consider building a 13B.

Many of the parts work with either engine (especially if it is a pre-'86 13B), but apex seals and some gaskets would be wasted if you bought the 12A stuff, then found the housings to be bad, and then decided to go 13B.

There are some other good threads floating around about rebuild parts (vipernicus42's "Ultimate 12A" thread comes to mind).

Check on here and some other sites to find new parts that maybe someone didn't use. This is a good way to save cash. For instance, I bought a set of OEM apex seals and the metal carriers from a guy that got them when he bought one of his part cars. The previous owner intended to rebuild the engine, but never got around to it. The result was getting new OEM stuff for a good price. Also, sometimes people buy some rebuild parts and then run out of money to finish the project or they decide to take a different direction (like go 13B instead of 12A).

 

Hey Tony,
Glad to see that your thread is getting a lot of great advice! I see trochoid and gslse-addict and Karack (the man!, my engine builder) have all given excellent information. Hopefully your housings aren't as toast as mine were. If you want to buy new ones I can refer you to some places that have a only a few sets left.. at least last time I talked with them

 

Well it's looking like this weekend I will know what surprises my 12a holds for me. I will try and post some pics of the engine so I can have a before and after. We should have a RX7 make over show. We need an Oprah for the RX7 world, have her donate some new parts and monetary donations. LOL is good to dream.

 

do mazda dealerships sell these seals and such??

 

Dealerships can order them, if they feel like it, but bring the Vasoline with you.

 

uh oh.......

 

What trochoid is saying is that will charge you an arm an a leg for them. LOL

 

I thought he was saying you'll get screwed?