ok, let me take this a step further. Is there a difference between T2 and FD housings?

no.



I would go with an fd motor. A lot easier to located the irons if you blow the moto https://www.nopistons.com/forums/pub...DIR#>/wink.png

Yes there is.



The FD rotor housings have a different kind of final coating on the steel liner but I'm not sure what it is. It's supposedly superior to the older stuff and is more "self-lubricating".



The Cosmo rotor housings have a different casting on the exhaust port -> DO NOT USE THEM. The port opening timing runs its way down like a ramp instead of being flat at 90 degrees. Even with T2 exhaust sleeves in them, the bottom of the sleeve interrupts the flow of exhaust and sticks out. I won't ever use them again.



B

Can you elaborate a little more on this? What do you mean more like a ramp vs 90 deg? Is there a picture somewhere I can see? Maybe a side by side pic of a FD and Cosmo housing. Would it be possible to cut the T2 sleeve in the area where it interrupts flow?

Learn something new everyday https://www.nopistons.com/forums/pub...IR#>/smile.png

you around Brian? https://www.nopistons.com/forums/pub...R#>/unsure.png

Fd housings had a graphite coating from the factory, earlier motors had a fluorocarbon polymer on the housings. This coating is to reduce wear from initial startup and possibly a little into break in, any housings you see that arnt new will have no coating remaining anyway.

i dont think that coating matters much fi any at all, IF there is a difffrence at all

i have seen made fd housings and older housigs with similar milage and they seem

to be about the same

Copmpared to FD Cosmo 13B has bigger inlet ports, an 'allegedly' better inlet manifold, crank angle sensor as opposed to crank trigger ignition and much more restrictive exhaust ports and exhaust manifolding Made a bit less power, but a bit more torque at lower rpm.

In the 20B the inlets are hooge & power was contained to the supposed 206kW the same way, with masked exhaust ports & a insanely restrictive exhaust manifold & turbos.

A 'gun' 13B build would be FD housings with Cosmo plates and a good terb, but that said I have seen an unopened import Cosmo 13B with a big single make 402 at the wheels.This would be most pleasant.



A 20B done this way, however, would verily be The Finger Of God, coming soon to an Rx5 nowhere near you!

I gave up on my 20B in my CD Cosmo project in favor of doing a smaller car. You Aussies call them RX-323s when somebody puts a 12A or 13B into one. I wonder what I should call mine? https://www.nopistons.com/forums/pub...IR#>/smile.png