I was wondering about what the differences between the different housings are. I know there are 4 different 2nd gen motors. The s4tII, s5tII, s4na, and the s5na. I know the rotors for the s4's are half a pound heavier. I know their compression ratios are 8.5:1, 9.0:1, 9.4:1 and 9.7:1 I was wondering what the different port sizes and other measurements are. Also I would like information on mixing different combinations of rotors, aluminum housings, and iron housings. Can you use s4na irons with s4TII aluminums with S4na rotors, using a s4 wireing harness, manafolds, and ect? How compatible are they with one another?

 

bump

 

it might be easier to ask what your trying to do? What motor are you working on and what do you want to do with it?

 

I am mostly asking out of curiosity. I tried searching, but could not find anything.

 

general rule....
port size is the same for turbos, and for n/a's, but not turbo-n/a..

you can mix anything you want, but if you use s4n/a rotors, use the flywheel and counterweight too...same for all the others.

irons are not interchangeable from n/a to turbo, but the rotating assembly is.

rotor housings are interchangeable, but it's more desireable to use turbo rotor housings.

any more questions?

 

one correction to your notes. You can use a tii intermediate housing on an na. gives you kind of a cheap street port. Also, if you use tii rotor housings you must contend with the water passage - easy to do, if you plan for it.

 

If i had a s5 short block, could i put s4 manafolds, wireing harness, and ecu on it?

 

Also the NA rotor housings have exhaust diffusers while the turbo housings don't. But you can remove it or grind them out.

 

What is the purpose of those things in the exhaust ports of the na

 

touche.
overlooked that one.

 

they are exhaust diffusers.

 

and what is the purpose of exhaust diffusers?

 

they knock down the noise

 

yeah. they "diffuse" the exhaust pulses to help smooth out the exhaust.

 

and tones the volume down a bit

 

If i had a s5 short block, could i put s4 manafolds, wireing harness, and ecu on it?

yes, but you'll have to swap the front cover to an s4... the s5's have an electric omp, while the s4's are mechanical.

 

Hex 7e I think the spark plug holes are in a slightly diffrent location between S4 and S5 N/A housings. Oh by the way that counterweight thing you were asking me about the other day, The one on the locked up engine is from an automatic trans. That friend of mine bought 2 RX-7's one had a locked up engine and the other was wrecked and had an auto. he bought the wrecked one for the engine. I hope that answers your question. BTW, How do those engines I sold you look on the inside? Do you think you could make one from the two?