Bolted up a new set of heads and set my unmodified FAST92 bottom on them to see how the ports matched up. They all look like this. I was thinking if anything it would be the other way around. Is this normal?

 

I would have thought it'd be the other way around. What heads are those and what are the specs? I know Brian Tooley has always said that port matching the FAST intake to the heads is the ONLY way to go. He doesn't even like to port the FAST intakes without port matching. He said it's a waste of time.

 

It seems the port shape of the head is different than the port shape of the intake. This is an aftermarket casting. The ports matched perfectly when I had cnc'd factory castings.

 

Are those heads milled down? It looks like the top and bottom are shifted. Those are ported heads and they rounded the ends of the port.

 

Yes, They were milled to 59cc.

 

Might be part of the problem. If they get milled a lot your intake may not line up although it's usually shifted the other way so maybe there was something dimensionally different with another casting. The different shapes of the ports have to be adjusted on one or the other

What heads are they?

 

I've contacted the manufacturer but haven't received a response. That's why I'm posting here.

So it's a problem? A big problem?

I'm not convinced its a problem. I just don't have experience with a bunch of different builds so I was curious if this is normal. I doubt I'll be pulling the heads so can port them to match the intake.

 

It is not normal. My 243 heads matched up perfectly to my FAST 102. Can the car work like that. Yes. Will it be the best. No. You'll have air slamming into the lip causing turbulence and limiting flow.

 

What aftermarket castings are these?

 

They are Mamo Motorsports 235's (AFR castings).

 

A head porter chooses a shape he wants the port. He knows what shape the FAST is, he designed that port, either you trust him or you don't.

I am not saying this as a blind supporter honestly I don't see me ever using a AFR or Mamo product, but again, you trust him, the community trusts him. I think you are making a mountain of a molehill. It is a little in a corner, not like a whole side or perimeter.

 

I agree. Maybe the pictures aren't doing it justice, but I don't really see an alignment issue except maybe the radius in the bottom corners, but I wouldn't even think twice about that.

 

I'm not making a mountain out of a molehill. I even stated that I wasn't convinced it was a problem. I was just asking if it was normal. It seems everyone agrees its nothing to worry about. Thank you.

I've spoken with Tony since I made the post and he says all AFR cathedral castings have had that shape since like 2004.

 

Guys,

Please see my emailed response to the OP which I copied and pasted below in blue (with a few words added for better clarity). FWIW that's the older style 90/92 mm intake and I'm almost positive the 102 has a larger radius build into the corner......either way the comments I make below still apply. As a head designer I'm not going to design a port with sharp corners knowing that adds volume and inefficiency to the design. Also.....FAST intakes aren't the only manifolds that can be bolted up to the heads.....just the more common intakes most read about here.

Hope this clears things up

Scott,

The floor is raised on the AFR and MMS stuff because there is very little airflow on the floor of any intake port and even less on the tall cathedral deal.

It helps reduce the dead area of the port and increase the airspeed where the air is actually moving (roof and center of the port).

The slight lip.....don't even sweat it.....every AFR cathedral since like 2004 has had something similar (a more generous corner radius).

Its a non event cause like I said if you probed the intake port with a pito tube (or any device that can show the movement of air), the port the floor is very inactive and its only a small mismatch anyway.

Also.....air doesn't flow in sharp corners which is the other reason its there.....ideally the intake would have had a larger radius designed into it

If you were to match it perfectly it wouldn't be worth a single HP

 

Thanks Tony.

 

Something something nitrous outlet puck intake floor something.