I just got a rebuilt 87 n/a engine, and when I was looking at it the rotor housings were switched around. Does this matter any?

 

come on people, i don't want to have to put in the engine and have it be bad and have to turn around and pull it back out again. someone please help.

 

Hmm, there was a thread earlier this year from a person who bought a rebuilt engine from someone and the rotor housings were switched and he had a lot of difficulty in passing smog

 

ONLY if you have to pass emissions. If the rotor housings are switched, there is no path for the PORTAIR to go to from the ACV. We went through this with JRAT when he couldn't pass emissions. Turned out he had switched housings. I have a spare set laying around and examined what would happen if they were switched. The path for the PORTAIR is effectively blocked. If I remember right the path for the EGR was effected also. Not sure about that one.

 

I searched for the post, couldn't find it. Thanks for the back-up Hailers!

 

Yeah, it was me...The housings were swapped so the motor wouldnt pass emissions. Also it ran REALLY rich. I dont know if that has anything to do with it. You may want to consider swapping the housings.

Rat

Edit: I just noticed you are in Cali...Not a good place to have a car that doesnt pass emissions. Unless you have some "friends" that will pass you.

 

Swapping the housing can be expensive. I'd only do that if I had to pass emissions each year. If you do have to pass emissions, then by all means put them where they belong, because its that or bust your ***** trying to pass emissions. It would be like trying to pass emissions without the air pump.....almost. Still would have split air, but that only happens when the throttle pedal is depressed. No worky at idle. Cheeze, lot of dough to take it apart and put it back together. Say bye bye expensive black speghetti(sp, I ain't got time) orings.

 

Ok RIPTYDE......Whats your decision???? We wanna know. Please. Thank you.

 

Yeah! whats the verdict?

 

so does this help improve HP? id do it my self if it does. i got some shops that will pass me for like $250 dollars though.

 

while everyone, as you know i do live in cali and i do have to pass emissons test so i'll send it back to mazda recycling where they will fix it on their budget and give a good motor.l

P.S. I asked mazda recycling if this mattered and they said it didn't.

Thanks for the help

 

It does make a difference and if you need a explanation I can provide it. Maybe not coherent, but an explantion. The acv supplies air from the airpump to the exaust ports. It enters the exaust ports at the diffuser that is pinned in each exaust port.

The path for the air is from the airpump, to the acv, out the acv thru that silver dollar size checkvalve in the intake manifold, thru the intake manifold and out the intake manifold into the top of the rear side housing(very last plate on the engine). It enters that rear side housing thru the rectangular hole and follows a internal path down to the bottom of that housing, where the air exits a triangular hole that faces the rear ROTOR housing which has a similar triangular hole to match the rear side housing. Now if the rear rotor housing is truly a rear rotor housing, there will be two holes in that trangular hole. One leads directly towards the exaust manifold where it is blocked by the exaust gasket, and the other passage it to the rear exaust diffuser where the air mixes with the exaust gas.

Now if you put a front rotor housing where there should be a rear rotor housing, you find that that trangular hole in the rotor housing has but ONE passage instead of two. That passage goes straight into the exaust manifold gasket where it is blocked by the gasket material. The other hole does not exist. The one that should have gone to the rear exaust diffuser i.e. no fresh air being fed to the exaust.

I described the path to the rear rotor housing diffuser. The path to the front rotor housing diffuser is similar.

 

Tell 'em to just think about it. Why do the front and rear rotor housings have two seperate part numbers??????? Ain't because one is purttier that the other. You'll notice no difference in appearance, unless you look at the bottom right side of the housings at the trangular hole I mentioned that faces the rear side housing. On the rear of the rear rotor housing you'll see that the triangular passage has two outlets, but if you look at the trangular hole on the front of the rear rotor housing you'll see there is but one outlet. Swap housings and you get a blockage to the diffusers.

 

Those are the same MORONS that built my worthless motor. And they wouldnt take it back. Someone here on this site knows the builder, and needs to go over and SMACK HIM UPSIDE THE HEAD FOR BEING SO DAMN STUPID!!!!!......

Jesus! Somene really needs to go over to Mazda Recyclers and straighten them out!

Rat

 

Here it is, JMSEVEN knows the builder...

https://www.rx7club.com/forum/showth...5&pagenumber=2

 

Didn't these guys screw one up before? I have never checked to see if this is possible; I COULD BE FULL OF ****; but could they be using 2 front rotor housings to compensate for a lack of usable rear housing cores?

 

They are the same ones that rebuilt my $1200 paperweight in my garage...

Rat

 

Sorry to hear that Rat!

 

Thanks,

Lesson learned. Its still a decent motor, its just worthless to me since I live in Tucson Metro which means that I have to get emissions done all the time. Someone here on this site will post needing a running motor soon, and I will sell it to them for cheap. Swapping the housings will not gain or decrease performance. It just screws us in guys in emissions states.

Rat

 

J-RAT, i called back up there after getting the info from you guys and they told me they wouldn't take it back either, then i talked to Jeff, the guy who sold me the engine, and he said that i could trade it in for a correctly rebuilt motor.

 

What about me? I have tried to get those fools to take mine back, but they wont...

Edit: I am glad that you are getting your motor replaced though! I am just a little bitter, since I had to buy 2 motors for my car. I have the motor they sold me, but it just sits in my garage. Has about 1000 miles on it...Worthless....

Rat