Exhaust manifold condition & porting - advice please!

[CerbWill]

I've just taken these manifolds off my car due to a small exhaust leak from between the flange and the cylinder head. I'm planning to use ACT's gaskets when I refit them however when I took them off I was surprised to see the state of them in the pics below. I think the finish looks quite poor and the large step change in cross section can't be good in my opinion, but I'm no expert. So, is this normal/acceptable or should I get the dremel out?

Cylinder 2


Cylinder 4


Cylinder 6


Cylinder 8



Cylinder 1


Cylinder 3


Cylinder 5


Cylinder 7

[pmessling]

Normal, when i last welded the cracks on mine i smoothed it out a little, don't go mad as it will get to thin and crack even quicker.

[scotty_d]

As Peter has said this is normal, the Act manifolds match the head porting shape much better over the originals

[ukkid35]

Could it be that the design is intentional, making use of the anti-reversion effect?

[a1rak]

ukkid35 said:

Could it be that the design is intentional, making use of the anti-reversion effect?

Hi Paul, you are having a laugh?. Its built like that because you couldn't see it when its bolted on the engine so PW didn't give a toss.

[QuiteQuietCerb]

I am also fitting replacement manifolds, found an oem pair new (old stock)! and would be very interested in any porting advice.

Thanks

[HarryW]

a1rak said:

ukkid35 said:

Could it be that the design is intentional, making use of the anti-reversion effect?

Hi Paul, you are having a laugh?. Its built like that because you couldn't see it when its bolted on the engine so PW didn't give a toss.

It's the exact opposit of anti-reversion... The smaller dia pipe also negates the advantage of the flat floor port.