Acquiring a 20B....
 

Having a rough time finding one, was considering ordering one directly from mazda as to not need a rebuild, not sure if they still do that though.

Found this: MAZDA RX7 COSMO EUNOS TWIN TURBO 3 ROTOR ENGINE LOOM ECU JDM 20B SERIES C | eBay

Don't know if that's a good price, seems reasonable, found a rx7 5 speed for roughly 3500, so the whole front clip for 10k doesn't seem too bad to me. Not an educated opinion, however.

check mazmart. hope ya got 30-50k saved up

Thanks, I did look on mazmart, and didn't find any 20b's for sale.

There all gonna be in the 6-7k range in need of a rebuild. The rebuild may cost another 6-7k. You will be at 12-14k just to have a working engine.

Its not gonna be a simple as buying a junkyard 20b and mounting it in a car.

I'm assuming the rebuild is going to cost around that figure, maybe more, and have accounted for that. Don't want just an average rebuild, want something nice and relatively bullet proof.

I've got a sizable amount set aside, minus about 3-6k for a project car to do this to, not going to use my current RX8 as a guinea pig, plus I'm not in love with the velocity red, would prefer white, feel like that's just the best color for the RX8. Gonna keep the red one for a nice DD while the other one I'm looking to purchase sits being rebuilt in the garage.

So, besides the Ebay one I just linked, anyone have an idea where I can find one, preferably already built? Or is this something I may have to commission from a shop? I can do many things, I'll have a lot of tools and a lift soon, but rebuilding a 20b is not one of those. :cool:

i wouldnt get one already built because it may not be how you want it done. are you going single turbo or n/a? power goals? porting? once you open this can or worms the term bullet proof doesnt exist in reality depending on your build specs. i hope you get it done but its very expensive and a very long process

Not endorsing them, just a site I've used to get a ball park figure on cost for 2 and 3 rotor builds. Also have not sure on quality/experience with the shop, but the price points seem at par with other places I've research. Like 200 said, hope you saved your pennies...
DEFINED AUTOWORKS - Service | Repair | Performance for Mazda RX7

Single big turbo. 500-600 hp. As far as porting goes, I've read that the peripheral port can be ungodly loud, however I defer to the experts as far as what would be best for my application.

Thank you! That's exactly what I was looking for.

If you going to be in it for 15-20k for the 20B, I say skip right to the 26B for another 10k and forgo all that turbo stuff for the 500-600hp.

heh, this will be a streetable car, once you get into that range well...it's pretty much just a race car.

Contact Rob at Pineapple Racing or paul@mazmart.com

Appreciate the info, will add that to my list.

You don't need anything special to get to 500HP with a turbo. Peripheral porting isn't necessary unless you're trying to make like 1000HP with a turbo

Bulletproof + rotary = :lol:

Getting to 500WHP is pretty easy on an REW or 20B, maintaining it is the problem.

It's my understanding that the 20b can withstand that sort of pressure for longer, as it doesn't have to work as hard. Correct me if I'm wrong there.

If built by the right person and tuned right on a quality single turbo setup, possibly. The Rolex series RX-8's ran a NA PP 20B and made 550WHP. But of course that is on a race header, race ECU, etc., etc.

My buddies single turbo, 20B RX-8 "ONLY" made 455WHP. It was rebuilt once in his ten+ years of ownership.

I think I could deal with a measly 455WHP, that's over 500 at the engine...and really it's all about how it feels, 500 is more an arbitrary number than anything else, I imagine an RX8 even with 300 hp is going to go like a rocket ship.

Yeah, 10 psi on a 20B can reliably (in rotary engine terms) make 550 rwhp if you choose wisely. You should seriously be considering the new Adaptronic standalone PNP ecu for doing this in the RX-8 chassis

Will add that to my list. Right now, looking to buy a car I won't feel so bad about tearing apart, it just feels wrong to completely gut a perfectly working RX8 with 70k miles, good compression and nothing at all wrong with it, bone stock.

Plus, I kinda want a white one.

Interesting...

That whole clutches grenading seems scary, might as well look into that now...

On a side note, I might be able to get this car: Used 2005 Mazda RX-8 in Phoenix
For about 2-3k, called about it, and apparently they are taking it off their lot, the motor is blown, so we'll see. Fingers crossed.

My favorite year/color :)

Yeah his RX-8 was stupid fast, faster than his R35 GTR. he sold all his cars and drive a Mclaren now though.

Yes! They agreed to sell me the car as is for 3k, which I'm probably over paying a bit for but....screw it.

Gonna have a friend have a look and pick it up, or have it shipped to my garage.

And yes, white on an rx8 just looks spectacular in my opinion. It's strange because I don't particularly care for it on other cars...

So now that I will have an rx8 that I won't feel bad about gutting, I can take the next steps and show everyone how ignorant I am about what I'm trying to do, haha.

Thanks for the advice everyone, it's much appreciated.

Well good luck, would love to see this completed ...





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FYI 20B Ebay Good for NA, 9.7:1 compression rotors

Might want to ask the seller to verify the compression ratio and rotor weight. It may have the 89-91 9.7-1 N/A rotors or it may have the slightly heavier 86-88 N/A rotors with 9.4-1 compression. Either would be fine, but the lighter 9.7-1 rotors would be the preferred option.

Having problems just getting the car, paid for it, but they are having issues due to the fact the car needs emissions, but no way in hell will pass emissions with a broken motor.

My ignorance is showing when looking at that 20b, weirdest looking intake manifold I've ever seen lol.

You know, the motor that was built and never run before, and on ebay no less, would scare the crap out of me. It just seems too good to be true ...

I'll just post this here ...

Still looking for a 20B?
 

I have 2 20B motors that I will be parting with. One is in the car...C Code with new 13B housings. The engine has 2500 miles on it and was built by Banzai Racing. Unfortunately the fuel pump failed during the dyno tuning and warped the seals, so it needs a rebuild. I've given up on the project and will be selling the car as well. It's a yellow 2004...originally owned by Tito Ramos. I have the engine he built also...the housings were all (undisclosed) shot when I bought the car. I have three 20B housings in great shape that came out of my core engine that will go with it. The only thing it needs is one more rotor. It has a C front cover and the other irons are A series. It was "unconventionally" pinned, but Banzai didn't recommend it for high HP.

Just a couple ideas. Feel free to PM me if you're interested. Everything is located in northern Indiana. The car is still at Banzai.

Cheers,
Gav