Sticky beak @ CHI 4v's - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

brenx · 02-07-2006, 17:50

I thought a few of you guys might want a peek. I have a full res pic if anyone wants a closer look.

falcon coupe · 02-07-2006, 19:01

Yes please !!

xb351coupe · 02-07-2006, 19:07

I'll take 2, could you wrap them for me !

4Vman · 02-07-2006, 19:19

are they direct bolt on replacements for iron 4V's? ie: same inlet port size and location?

brenx · 02-07-2006, 20:53

Quote:

Originally Posted by 4Vman

are they direct bolt on replacements for iron 4V's? ie: same inlet port size and location?

Yes identical just like the 2V versions.

4Vman · 02-07-2006, 21:25

Quote:

Originally Posted by brenx

Yes identical just like the 2V versions.

Excellent! i'll be interested to see the kind of power they make, if its significant there goes the myth that 4V ports are too big to make decent power!

brenx · 02-07-2006, 21:35

Quote:

Originally Posted by 4Vman

Excellent! i'll be interested to see the kind of power they make, if its significant there goes the myth that 4V ports are too big to make decent power!

Even though these have 4V port locations I think you'll find deficiences in the cast iron 4V's have been reduced in the alloy version. For example : The opening might be the same size but the runner won't be.

From what I can see, this is what is happening. The port gets smaller the further you move into the head. It's a bit hard to tell with the top one on the angle though.

4Vman · 02-07-2006, 21:49

Quote:

Originally Posted by brenx

Even though these have 4V port locations I think you'll find deficiences in the cast iron 4V's have been reduced in the alloy version. For example : The opening might be the same size but the runner won't be.

From what I can see, this is what is happening. The port gets smaller the further you move into the head. It's a bit hard to tell with the top one on the angle though.

Actually If you look at a cross section of an iron 4V head it dramatically tapers upwards from the manifold face to the tight radius in a similar fashion, the port fillers actually fill this area to leave the top 3/4 of the port to flow.
As you know the iron 4v port is higher in the head than the 2V port hence it gives a straighter shot at the valve.
Ill be very interested to see how this head performs against the 2V and 3V versions.

Am i correct to assume the 3V version is just a copy of filled iron 4V port placement? (obviously with better shapes and better exhaust port.

brenx · 02-07-2006, 21:57

Quote:

Originally Posted by 4Vman

Actually If you look at a cross section of an iron 4V head it dramatically tapers upwards from the manifold face to the tight radius in a similar fashion, the port fillers actually fill this area to leave the top 3/4 of the port to flow.
As you know the iron 4v port is higher in the head than the 2V port hence it gives a straighter shot at the valve.
Ill be very interested to see how this head performs against the 2V and 3V versions.

Am i correct to assume the 3V version is just a copy of filled iron 4V port placement? (obviously with better shapes and better exhaust port.

Incorrect the CHI 4V isn't just filled. If it was, you'd have to also epoxy your manifold to get it to match. Hence the ports perfectly matching up to any 4V running gear. That's why I said it looks like the opening is 4V but it tapped down as it reaches the valves and combustion chamber area?

Fire me off an email and I'll send you the high res pic. Let me know if you see the same as I see?

brenx@internode.on.net

4Vman · 02-07-2006, 22:11

Quote:

Originally Posted by brenx

Incorrect the CHI 4V isn't just filled. If it was, you'd have to also epoxy your manifold to get it to match. Hence the ports perfectly matching up to any 4V running gear. That's why I said it looks like the opening is 4V but it tapped down as it reaches the valves and combustion chamber area?

Fire me off an email and I'll send you the high res pic. Let me know if you see the same as I see?

brenx@internode.on.net

Sorry my bad, i meant the CHI 3V has same port locations as filled 4V iron heads!

Email on its way.