Hi there,

I am looking at buying parts to build up a new 20b.

I would like to know what the best rotor housings are to use for a 20b build - I want to buy brand new ones.

I noticed that mazdatrix sell the '20b' housings but I have noticed others using 13b housings.

I called a local mazda dealer who gave me a price on the FD rotor housings but both had different part numbers, probably for front and rear... Would these be more ideal over the 20B ones? Would it matter which part number I purchased?

Thanks

 

yeah u can use FD housings

infact they are prefferred over the 20B ones.. as the exhaust sleeve is much larger and they flow alot better

 

I have Brand New:

20B housings

and

FD3S Housings

If you are serious about buying them.. pm me..

 

This wasn't a WTB thread, I was asking for info.

Besides, we both know it would be cheaper for me to buy them locally...

 

It is not a matter of 13B housings being "preferred". I think most people that use them only do so because they have them available. I would not mix them in an engine. I prefer 20B housings when building 20B engines, just so the numbering stays consistent. It does not hurt that they are $250-ish less expensive then FD housings, either. It is a very easy task to swap exhaust sleeves.

 

are sleeves sold seperately? or do u just have to find and pull them from used FD housings?

 

20B New rotor housing are NLA, so you can't buy them from Mazda.. They don't have any to sell.
I stocked up on them a few years back and have 5 brand new sets... 15 housings. I am willing to sell 1 or 2 sets but they are
not cheaper then the current price of FD3S housings.

 

Wrong. You can still buy the front rotor housing for $514.88, it can be used in any location, just have to drill out a couple holes. Same thing you have to do to use FD housings.

I bought the last of the center rotor housings back when they were $400.00 ea


I am not aware of the exhaust sleeves being sold new, we just pull them out of blown TII/FD housings.

 

Really.. who has them for sale?

Just because you see it listed on the Mazdatrix website... and @ that price.. Does not mean they have it, nor does that mean they can get it...

20B rotor housing have been NLA in Japan for a long time now... and the few Mazdacomp USA had... I am sure are gone...

 

EDIT: 4 Left via Mazdacomp

If I didn't already have plenty I would buy them and sit on them...

 

which means they ran another batch, like the s4 t2 rotors a few years ago

 

There you go, you answered your own question, they are available and they are much cheaper than FD housings....

 

So the only reason why the FD housing are preferred is because of the size of the exhaust port?

Thanks for your replies Banzai Racing

 

Not the size of the port, but the design of the sleeve

Here are the standard 20b, :

 

Would anyone have the dimensions of the box the housings come in with a rough weight? I am trying to find out how much shipping would be.
Thanks

 

Ooh that's a nice fd.

 

Are those exhaust sleeves unique to the 20B housings or are they used with other housings (cosmo, etc)? I looked through Banzai's web site and the housing description they have posted but these sleeves are not with the lineup....

I got a set of housings with these sleeves and changed to the FD sleeves but the FD sleeves do not seem to extend all the way to the combustion chamber port (about 1/16" short). Also had to cut the EGR tube down in the port to fit the FD sleeves. Just FYI.

 

The same sleeves are used in the Cosmo 13b-re engine housings

We do not have them in the housing ID FAQ, simply because the engines were not available in a car here in the US. The majority of people are trying to identfy the housings that we have listed

The 20B housings are a dead give away

 

So what is the going rate for a set of housings?

I tried to email mazdatrix but it keeps being rejected. I cannot call them because my phone does not let me dial an international number...

Rather annoying...

 

Here are the RE/TII sleeves TII on the right.

 

That is noticeably larger thats for sure - thanks for that...

Japan2LA - I sent you a PM...

 

It is larger but not by a HUGE amount like that pic shows. That pic is at a bad angle.