Blue/black head

[DANNY8]

I'm buying a VK wagon, and it has a 202 black motor in it. I checked the engine code and apparently it is the high compression model. The motor is coming out, and I'm putting my mild 173 (now 186 ) 5spd in it. My blue 173 had a high compression head as well. But I read in another thread that the black heads were a bit better design, then someone else said they're the same, so I'm wondering if there would be any advantage of putting the black head on my motor? I got new crow valve springs on my blue head, but they'll go over onto the black head if I decide to use it. Also the motor in the wagon isn't original as it says 'RAPID EXCHANGE ENGINES' on the top of it, so I'm guessing it was once rebuilt, which I'm thinking if thats correct then it might have the newer valves to run unleaded.

So here's wat I wanna know:

Which would be a better head to use, a blue 173 HC, or a black 202 HC?

Cheers,
Danny

[Shifty1]

Not 100% sure, but i dont think the black head's ports line up properly..

[stroke it]

The black head is alot better, its about equal to the old stage 3 yella terra as they'll flow around 180-190 horsepower.
er... Use the 202 black head and inlet/exhaust manifolds from the black unless you have extractors to go on it of course.

[frenchyvh]

the 202 black head will lower your compression. If you've gone for the extra cubes on the 173 then why would you run a black head on it which is designed for 202 cubic inches??? I think you'd have much better power gains from your existing 173 head.

[DANNY8]

Not 100% sure, but i dont think the black head's ports line up properly..

Nah I'm pretty sure they do, coz blue/black intake and exhaust manifolds are interchangeable.

The black head is alot better, its about equal to the old stage 3 yella terra as they'll flow around 180-190 horsepower.
er... Use the 202 black head and inlet/exhaust manifolds from the black unless you have extractors to go on it of course.

My blue intake is currently sitting in the acid bath, so will be using that. And the VK already has a decent set of extractors (we now have 5 sets of extractors haha) so I'll be using them. Once the motor is run in tho I'll be chucking all the EFI gear on it. Might get a dyno run with the carby on, then another after the EFI is on and see actually how much improvement there is.

the 202 black head will lower your compression. If you've gone for the extra cubes on the 173 then why would you run a black head on it which is designed for 202 cubic inches??? I think you'd have much better power gains from your existing 173 head.

That's one of the things I wasn't sure about. But if the black head is overall better, I could always get it shaved to bump the compression up again. I've also been told the 173 heads had smaller valves, not 100% sure on that tho.