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House of Darts 12-25-2016 01:10 AM

273 heads
 
920 or 675, one flow better than the other with 273 2bbl or 4bbl or is the 302 swirl port better?

David Lee 12-25-2016 02:30 AM

Re: 273 heads
 
you will get different answers from different people. what are you building?

GTX JOHN 12-25-2016 03:32 AM

Re: 273 heads
 
We run 302.

House of Darts 12-25-2016 11:53 AM

Re: 273 heads
 
I built a motor a while back and had a series of bad rides that became too expensive to repair. Pieced out the motor. Just found a '66 Valiant that needs just a few repairs to the body to get it ready race. Starting from scratch again with the motor. 4 BBL combo. I got the 302 head to work with a bracket motor but I did extensive port work. So as a stocker, I'm looking for dime rocket parts.

James L Miller 12-25-2016 03:54 PM

Re: 273 heads
 
I'm in Tampa ready to drop off a set of 920 and 675 heads to my machinist/engine builder/friend after the Christmas holidays. I brought a box of valves to flow. Not sure when he will get around to them though. He's always busy with projects. I'd probably forge ahead with the 302 heads if I had a set. David and I are e-mailing on our projects. Join the 273 Stocker gang. Not sure this will be a dime rocket though.

David Lee 12-25-2016 07:57 PM

Re: 273 heads
 
Quote:

Originally Posted by House of Darts (Post 523120)
I built a motor a while back and had a series of bad rides that became too expensive to repair. Pieced out the motor. Just found a '66 Valiant that needs just a few repairs to the body to get it ready race. Starting from scratch again with the motor. 4 BBL combo. I got the 302 head to work with a bracket motor but I did extensive port work. So as a stocker, I'm looking for dime rocket parts.

Sent you a pm

65signet 12-26-2016 07:17 PM

Re: 273 heads
 
I am working on a set of 302 heads right now, but i don't think any heads for a 273 are dime rocket stuff. It's not easy to make that little port work right .

James L Miller 01-07-2017 03:02 PM

Re: 273 heads
 
We got 178 cfm @ 28" (converted from 10" H2O) on one intake port on a 920 head. The stock valves with a back cut flowed pretty good. A Manley BBM 1.81" exhaust valve cut down to 1.785" seemed to be best at several points and averaged from .050" to .420" lift. I was kind of surprised that dinky little port (127cc) flowed that good. We never got around to trying any seat or bowl work. Ran out of time and money for the time being. The LD4B lost some flow as the port in the intake is wider than the head.

I think I might have to buy/build my own flow bench and get the tooling for seat work for my mill so I can spend the summer working heads. That's a time consuming process.

Coleydog 01-10-2017 12:38 AM

Re: 273 heads
 
Quote:

Originally Posted by James L Miller (Post 523869)
We got 178 cfm @ 28" (converted from 10" H2O) on one intake port on a 920 head. The stock valves with a back cut flowed pretty good. A Manley BBM 1.81" exhaust valve cut down to 1.785" seemed to be best at several points and averaged from .050" to .420" lift. I was kind of surprised that dinky little port (127cc) flowed that good. We never got around to trying any seat or bowl work. Ran out of time and money for the time being. The LD4B lost some flow as the port in the intake is wider than the head.

I think I might have to buy/build my own flow bench and get the tooling for seat work for my mill so I can spend the summer working heads. That's a time consuming process.

Funny just did the same thing for some 383 and 340 heads, Got some good 340 heads so I'll see how they make them work, reverse engineering. At least it will be entertaining. If you get them to work no more kissing butt to the big guys.


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