00' manifold vs 01' manifold
 

Is the 99-00 exhaust manifold the same as an 01' ?

99-00 has a very heavy cast iron manifold
01+ use a lighter tubular manifold

other than the material and weight will one fit the other exactly the same?

The EGR tubes are different, they bolt on the head all the same though and the exhaust should fit right up. Not positive about the exhaust fitting right up though.

ok thanks

I believe you have to replace the manifold, EGR pipe, and downpipe (B pipe?). Beyond that they all connect in the same place by the tranny.

well the reason I ask is that I have an 00' and bought a 01' 16g manifold. It bolts up but has a large leak in between the block and manifold at the rear. It sounds like open headers because of it. So I wanted to make sure that the two blocks were the same to narrow it down to a problem with the manifold..not fitment. I should say that the manifold is custom made too.

the block has nothing to do with it..the mani's bolt up to the head
i know for a fact that a 01 stock header will bolt up to a 99 head...the pattern is the same, only thing you may be experiencing is that
a. the "cuztum" mani is a piece of shit
b. you didn't tighten your bolt/or you stripped a bolt or two and they won't tighten up all the way
GL

or maybe the mani has an open EGR port?

well he said the leak is between the block (head) and the mani...well he also thinks the exhaust exits at the block, so there is no telling what is actually going on here

For whatever it matters... ALL 1.8L Miatas have the same exhaust bolt pattern.

Seems that your problem is with the manifold.

Did you make sure the coolant line mounting tab isn't wedged between the manifold and block?