Pinapple racing 13b semi pp
 

I just recently aquired a first gen 1980 and in a stack of Receipts I discovered is has a old NA pinapple racing semi pp 13b in it not sure the condition but I'm thinking I'll try to rebuild it but does anybody have info on how well built there motors are. Like is to rotationg assembly balanced or rotors clearanced for higher rpm operation or do they have solid dowls and whatnot. Also if it does happen to just run can they handle boost at all.
https://cimg9.ibsrv.net/gimg/www.rx7...33bb3f2418.jpg

welcome to the board. :)

Pineapple has a stellar reputation. they know what they're doing. as far as your questions go, you're probably best starting at the source. send them and email or give them a call - see if they keep build records, etc. everything you asked about can be found upon disassembly and inspection, so even if you don't get info from them or the previous owner, you can find it.

my question is have you tested the engine to see if it needs to be rebuilt?

can you post some photos?

Havnt had time to really do any testing to it but going to soak it in mmo this weekend and hopefully at least hear compression. My tester is at my dad's house though so I won't be able to get comp numbers for a while whole car needs rewired pretty mutch too so im not sure if the starter will work even if i jump it. Thing came with a fat stack of receipts and pictures so here's some old and current. Pretty sure it's a s4 or s5 motor
https://cimg4.ibsrv.net/gimg/www.rx7...2ec0e50dd.jpeg
https://cimg6.ibsrv.net/gimg/www.rx7...f48d42546.jpeg
https://cimg8.ibsrv.net/gimg/www.rx7...fc1367ae3.jpeg

from the photos (the manifold), it doesn't look like ports are cut into the rotor housings. can you confirm that they are or are not there?

I thought that ports on a semi p were just the water things that go to the manifold drilled out and sleeved to block the water jacket then the ports on the irons where still used too. The manifold looks like it has a 4th and 5th runner for this also. So you wouldn't be able to see them like on a full pp where the only port is a huge one out the housing

Rob (pineapple racing)passed away this summer. So I'm guessing the records are gone.

But he was a good builder and built engines for Mazda racing teams back in the day.

If it's semi p port, you should still be able to see if the intake manifold has runners that feed directly to the housings and the irons.

in essence, yes. that's exactly what they are.
again, you're correct. you wouldn't see a huge hole, like on a full peripheral. however, what you SHOULD see is evidence of a runner leading to the rotor housing (usually taken from the original secondary runners - but not necessarily), and all i was saying is that i didn't clearly see any evidence of that in the photos you posted. for the scope of your questions it's not relevant, i just wanted to confirm for my own personal curiosity. maybe it's the photos, but to me, it looks like it may be just a 6-port manifold.

holy ....

i did not hear about this.

R.I.P. to him ... and condolences to his family and friends. :(

If that is a semi peripheral manifold then it's probably a nightmare to tune the carb properly. And lots of experience with 6 port engines (and that's a 6 port) it probably doesn't make power anywhere compared to a stock port.

OTOH if Rob built it that way, he probably did it for a reason, and I'm just some guy on the Internet with an opinion. (And lots of weird experimentation with 6 port engines)

Glad someone on here ended up with that car. I was going over Saturday to buy both of that guys cars. Knowing Rob, it wouldn't surprise me if that car had a light weight flywheel of some sort too. Let us know what you find, as I'm pretty curious of "the one that got away."

You can see the runner for the PP in the reflection on the heat shield.