327 Engine code
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6th Gear
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327 Engine code
Need a little help from the experts I have a 66 roadster with 327 4 speed with engine code HR all numbers match vin on the car but everything I look up says an HR code is with powerglide this appears to always have been a 4 speed , no sign of any cooler line fitting in radiator or linkage changes etc. Any ideas would be greatly appreciated , Thanks
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From: Sitting in his Nowhere land Hanover Pa
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By chance do you have the info from your trim tag if it's a St. Louis body and any color but black that would help
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6th Gear
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Melting Slicks
Joined: Aug 2004
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From: Sun Prairie WI
Need a little help from the experts I have a 66 roadster with 327 4 speed with engine code HR all numbers match vin on the car but everything I look up says an HR code is with powerglide this appears to always have been a 4 speed , no sign of any cooler line fitting in radiator or linkage changes etc. Any ideas would be greatly appreciated , Thanks
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6th Gear
Joined: Oct 2013
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HR is base engine, powerglide, with California K-19 A.I.R. smog system. There is no "cooler line" fitting in the radiator for p/glide, as all small blocks used the same radiator. The p/glide cars had a separate small Harrison air-air heat exchanger in front of the radiator that circulated hydraulic fluid from the trans through this unit. Pic of my 'HR' '66 engine pad below.
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From: Washington Michigan
Need a little help from the experts I have a 66 roadster with 327 4 speed with engine code HR all numbers match vin on the car but everything I look up says an HR code is with powerglide this appears to always have been a 4 speed , no sign of any cooler line fitting in radiator or linkage changes etc. Any ideas would be greatly appreciated , Thanks
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
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6th Gear
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If the front block stamp pad looks typical, including the VIN derivative stamp, it was born a Powerglide K-19 and has been converted to a 4-speed at some point. If it was a Powerglide to start with, there will be two Rivnuts in the front side of the lower crossbar of the radiator support where the Powerglide trans fluid cooler was mounted. Got a good close-up hi-res photo of the stamp pad?
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
Melting Slicks
Joined: Aug 2004
Posts: 2,061
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From: Sun Prairie WI
If the front block stamp pad looks typical, including the VIN derivative stamp, it was born a Powerglide K-19 and has been converted to a 4-speed at some point. If it was a Powerglide to start with, there will be two Rivnuts in the front side of the lower crossbar of the radiator support where the Powerglide trans fluid cooler was mounted. Got a good close-up hi-res photo of the stamp pad?
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
Jeff
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6th Gear
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If the front block stamp pad looks typical, including the VIN derivative stamp, it was born a Powerglide K-19 and has been converted to a 4-speed at some point. If it was a Powerglide to start with, there will be two Rivnuts in the front side of the lower crossbar of the radiator support where the Powerglide trans fluid cooler was mounted. Got a good close-up hi-res photo of the stamp pad?
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
Your trim tag won't tell us anything, as you have a black interior, so the body-affecting options aren't coded.
Pad looks OK to me. 
Melting Slicks
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OK yes I forgot about the external cooler, but if that's the case someone went to great lengths to hide the fact it was ever a p.g. never have looked under a powerglide 66 but is the x member and exhaust mount and all that the , boy this thing sure looks like it was a 4 speed from day one , I guess its possible is there anny telltale thing I could look for?
Other tell-tale signs would be the routing of the speedo cable. A powerglide cable routes on the left side would have come with a cable clip on the left side of tunnel and no clip on the right side – see if one has been added on the right and how it was attached? The 4-speed cable routes on the right side and enters the firewall at a different location. Look at your AIM to see the differences in location and firewall plugs.
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6th Gear
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I’m surprised no one suggested looking at the Muncie numbers. A ’66 should have a 3885010 main case, which would be easy to obtain but also check the serial/date stamp (P….) and see if it has a VIN derivative stamp. It’s possible to get a date correct Muncie but the VIN stamp is probably not correct or missing. This is probably the second biggest tell-tale sign after the engine pad.
Other tell-tale signs would be the routing of the speedo cable. A powerglide cable routes on the left side would have come with a cable clip on the left side of tunnel and no clip on the right side – see if one has been added on the right and how it was attached? The 4-speed cable routes on the right side and enters the firewall at a different location. Look at your AIM to see the differences in location and firewall plugs.
Other tell-tale signs would be the routing of the speedo cable. A powerglide cable routes on the left side would have come with a cable clip on the left side of tunnel and no clip on the right side – see if one has been added on the right and how it was attached? The 4-speed cable routes on the right side and enters the firewall at a different location. Look at your AIM to see the differences in location and firewall plugs.