Wondering if anyone knows, or has measured in CC's the Intake and Exhaust Runners on a set of Stock 081 heads. I am currently porting a set and did not measure them before I started. They are way past stock now and I just want to use the info as reference to compare to where the ports are now. The last measurement was roughly 172 cc's with the valve in on the Intake side. The Exhaust is around 65 CC's.

Thanks !!!!

 

F-Bird'88, (our resident head hero), has measured 081 intake runner port volume at 167 cc. GM says 155 cc, but he measured it himself so I'd trust him first.

 

Thanks !!!!!
I found some info today that is very useful on SB and BB heads. Iwill post in under a new thread.

 

I measured 416 castings not 081's

The 416's have a big void in the roof of the port where the rocker stud pokes through. This is the extra volume.
Other than that the port is the same size as other typical sb ports.

 

My 081's are the same way. But you have it right. When you flowed the 225/140 cfm heads, was that with 184 or 194 valves?

 

That was with 1.94 x1.60valves.

 

Stupid question, but did you ever flow a set of heads with 184/150 valves that you ported? I hate to bug you but I am in the process of building a pretty wicked 305 combo to prove to the 350 and the Vortec World that a crappy 305 with 305 heads can run some decent numbers.

 

No crappy engine will make any decent numbers, especially not a crappy 305 with 305 heads. However, a heavily modified and tuned 305 that isn't "crappy" will I think everyone knows that. The argument stands, though. A 350, all else equal, will make more power.

 

I agree that 350's are the way to go, but have you ever just wanted to slam a good combo together and let it rip? I don't want to let the cat out of the bag yet, without driving the car. But I think I can pull some pretty good power out of my 305 before I demolish it.

 

No I haven't flowed ported heads with the stock 1.84" valve size.
But you could, and then when they don't flow much more than stock, you could then open them up for the larger valves and flow them again.
Some people have to learn the hard way.
We'll be waiting for you to tell us all about it.