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Discussion Starter #1
Would like to know if this is a dished piston or higher compression type. Trying to determine approximate compression ratio of SWMBO's new engine. Thanks.
 

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Here is a link to some TRW piston info. According to their chart, a 289 with 54.5cc combustion chambers will have a CR of appx. 9.12:1. Not bad for a street combination.
 

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Based on the technical info an my experience with actual numbers, your CR should be right at or slightly under 9:1, which shouldn't have an adverse effect on idling with this small camshaft.

Did you install the cam straight up, advanced, or retarded? If not straight up, how many degrees and which way?

Am I correct in assuming that the Holley is a List 4670 355cfm or List 7448 350cfm two barrel, not the List 4412 500cfm two barrel (or their modern equivilents)?

There's still a couple of unanswered questions from this thread concerning PCV, spark plug readings, ignition advance and detonation tendancies....when you get some time, update us..
 

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Discussion Starter #5
I believe the cam was installed straight up. The Holley is a very old "Economaster" but I can't see the list number.(where should it be - I forget) I replaced the original carb, probably in the mid '70's with this one. The engine rebuilder also rebuilt the carb and it is the one that was on it when it was tested on the dyno. The only smog equipment on it is the PCV valve. The pump and injector system has been removed and the ports plugged with the Ford plug.

The present spark plugs are Autolite #45. The initial advance when the dyno tests were run was 10 degrees. That is when the engine produced 200.5 HP at 4400 RPM.

I did not do a WOT run yet. Just pulled the #1 and #8 plugs. #1 looks a bit wet and some carbon around the shell. The #8 looks dry and less carbon on the shell. This car was started and run cold a lot around the body shop during the painting and re-assembly process.

Should I just put in new plugs and see what results? What would be a good choice for short run grocery getter duties with this engine? It only has about 125 miles on it plus the body shop start/stop stuff.

Thanks again for all the help.
 

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Should I just put in new plugs and see what results?

That is a good first step...IIRC, the 45 was the hotter range, so if you're getting any carbon (other than a light coating on the shell) on the new plugs with normal driving, then the carb needs looking at.

On 2300 series Holley two barrels, the list number is on the airhorn where the choke goes. I'm not familiar with the Economaster...does it have a removeable side bowl and metering block like conventional 4 barrel Holleys (like the typical 600 cfm units many VMF'ers use)?

From the symptoms you're describing and the appearance of the spark plugs, my instincts are that you're getting intermittent misfires at idle. I think once things are squared away, the 45 heat range (if OF memory serves *G*) should be fine....the plug readings after some use will tell the story. I think that's the heat range I run in the D-coder and they looked perfect (heat-wise) when I changed them last after being in for about 6 years.

Keep us posted!
 

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Discussion Starter #7
Will look further to find the list number. It's a 2 BBL with an orfice (metering) block and bowl off to the front as you describe. The "Econo-Master" came out during or just after the 1972-73 gas crunch. I will change the plugs to new #45's and let you know what happened. The distributor cap is the large blue Motorsport with blue Motorsport wires. Should be OK, but will check it out in the dark etc. Thanks again for the help.
 
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