D/Dart in Stock

Paul Ceasrine · 09-12-2009, 03:47 AM

I thought you guys were talking about D-Darts.The only difference between a 273 Hi-Po (235 HP) and the 273/275 HP (D-Dart)was the camshaft (Cam-Craft .495/.505 lift / 284 duration), and Racer Brown 250 lb. ratedvalve springs.The carburetor was a Holley 600 cfm-rated, vacuum secondary unit, as opposed to theCarter 500-cfm AFB unit on the 235 HP rated engine. To allow for the Holley carb butterflies to open, the stock cast iron intake wasmodified (a free-breathing flow intake as Chrysler put it), the throat openings were bored out an additional 3/16".It really doesn't sound like a 40 HP improvement over the 273/235 HP Commando.I think the NHRA currently rates the 273/235 HP at (220 HP). As someone posted earlier, the D-Dart engine should be re-rated.Not that it would matter, because who in the hell would try to run this car in stock class, and be competitive. Not at 275 HP.Paul (Former 273/235 HP racer)

09-12-2009, 03:47 AM	#19
Paul Ceasrine VIP Member Join Date: Apr 2009 Posts: 2,546 Likes: 0 Liked 10 Times in 10 Posts	Re: D/Dart in Stock I thought you guys were talking about D-Darts.The only difference between a 273 Hi-Po (235 HP) and the 273/275 HP (D-Dart)was the camshaft (Cam-Craft .495/.505 lift / 284 duration), and Racer Brown 250 lb. ratedvalve springs.The carburetor was a Holley 600 cfm-rated, vacuum secondary unit, as opposed to theCarter 500-cfm AFB unit on the 235 HP rated engine. To allow for the Holley carb butterflies to open, the stock cast iron intake wasmodified (a free-breathing flow intake as Chrysler put it), the throat openings were bored out an additional 3/16".It really doesn't sound like a 40 HP improvement over the 273/235 HP Commando.I think the NHRA currently rates the 273/235 HP at (220 HP). As someone posted earlier, the D-Dart engine should be re-rated.Not that it would matter, because who in the hell would try to run this car in stock class, and be competitive. Not at 275 HP.Paul (Former 273/235 HP racer)