B6 exhaust mani on B6

[zoe60]

OK, after reading the "B6 exhaust mani on B3" thread I got to wondering. I have an '89 323 engine in my festy and it runs great, but I still have the B3 exhaust manifold on it. I intend to replace it with the original B6 manifold soon. I've got the downpipe and I think it will all fit nicely. What sort of fuel economy and performance effects should I expect with the original 323 manifold? The rest of the exhaust is stock Festiva.

[ejp2fast]

what is your current performance now with a B6 engine and B3 exhaust manifold with festiva exhaust? mpg's? If you went back to your B6 exhaust manifold on your B6 engine, would you keep the same B3 exhaust?

[zoe60]

Yeah, I am planning on keeping the original festy exhaust from the cat back. I looked up the cat on rock auto and it is the same part no. for either a 323 or a Festiva. With the Festy manifold and down pipe I'm getting about 36 MPG. It runs pretty well but I keep thinking the 323 manifold would be better with it's longer pipes. Plus they are the correct size for the B6. I only used the Festy manifold when I put the B6 in because it was easier.

[ejp2fast]

36 isn't bad for the B6 engine / B3 manifold... maybe one of the other guys that have the B6 engine/B6 mani chime in for mpg numbers for comparison.

[M3NTAL]

So basically your asking what mpg you would get with a stock B6

I'm sure this question has been asked before.

And I'm sure there's 100 answers lol

[zoe60]

OK thanks. I'll just put it on and see.

[ejp2fast]

let us know your results...

[zoe60]

OK. It will be a tank of gas or so.