273 commando Build

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nobody believes me when I tell them it's a 273 commando . It has a nasty Growl , and it's really loud with the flowmaster 70 series mufflers. video doesn't do it justice .
Do you get any interior drone with those 70’s? I have Flowmaster 44’s (wasn’t my choice) and the interior drone is awful! Neighbors think the car sounds cool, though!
 
Do you get any interior drone with those 70’s? I have Flowmaster 44’s (wasn’t my choice) and the interior drone is awful! Neighbors think the car sounds cool, though!
ooops ! my BAD on the flow master mufflers . they are 40's series . and they have drone at 35-40 mph. love the sound ! I believe the 44's are a little quieter
 
ooops ! my BAD on the flow master mufflers . they are 40's series . and they have drone at 35-40 mph. love the sound ! I believe the 44's are a little quieter

Ran Thrush mufflers dumped just at the rear end also on my first Cuda about 1975/76....scarred a few dad's and me chased off as well.!

Here's those Fel Pro pages on head gaskets from a 1997 catalog.
Fel Pro shim 1.jpg
Fel Pro shim 2.jpg
 
Wow - I was wrong....maybe I was reading a base RPM ? Anyway got the mags back out to re-read and both were talking about 8000 to 8500 RPM after putting in stuff like 392 Hemi valves (cut down a little) and other stuff. The first mag is - Modern Rod's issue May 1965 with discussion's on the Dart Charger with Ed - Mr Isky grinding out a cam. That issue is on phase 2 of the hop up. The next mag is Speed and Custom's Aug 1966 with still more info about early 392 valves with grind info. The article follows some stuff the Golden Commandos did to - "Gold Fish " running their F/SA 1965 Cuda as well as the "Politician " another 1965 F/SA Cuda. The D-Dart of "Gendarme lll " running D/MP class was in the other mags as well. And the next is Rodder/Super Stock issue Jan 1968 with more on those 392 parts and some neat piston cutting. There was a rail job called - Silver Bullet " that was running a home made fuel injected 273 . They also talk of swapping sides of the pistons which they say gains some HP.

The "Gendarme III" was not a D/Dart . It was just a 65 Dart GT. The 50 D/Darts that were produced were 1966 Dart GT's.
 
Yes it was a 1965 running D/MP.....not sure if it was this Dart but one with the 2X4, 4.56 rear gears and a little more radical Isky cam ran a best of 107mph at 12.89 sec at Detroit dragway the magazine says....on 7 inch cheater slicks.
273 hipo.jpg
 
Stroker402,
Great build and thread.
Did you have the cc's measured on the heads or have you done a compression check on the engine, since it has been broken in? I'd be interested in those numbers.
Did you have the heads milled any? Did the compression end up where you wanted it to be with that cam?
Thanks, Richard
 
Stroker402,
Great build and thread.
Did you have the cc's measured on the heads or have you done a compression check on the engine, since it has been broken in? I'd be interested in those numbers.
Did you have the heads milled any? Did the compression end up where you wanted it to be with that cam?
Thanks, Richard
I haven't done a compression check after the rebuild yet but I will this spring .I did not measure the cc's on head compression hence the chambers were untouched. heads not milled either. (920 heads) just a little cleanup on the ports and a gasket match . I run premium 93 octane fuel . you can here from the exhaust that the 273 does have some compression. My previous 273 with flat tops had compression no less than 9 . I'll be posting the info on my compression come spring time. Thanks for the interest .
 
Car sounds great. Did I see that in the parking lot for the Fall Swap Meet in Wauwatosa, next to Kilpatrick's?
A little late now but I would have swapped you the LD4B off my 340 for your LD340, and could have done it with no shipping.
 
Car sounds great. Did I see that in the parking lot for the Fall Swap Meet in Wauwatosa, next to Kilpatrick's?
A little late now but I would have swapped you the LD4B off my 340 for your LD340, and could have done it with no shipping.
Yes, that was my barracuda at the swap meet this fall . I had a ld340 intake on the previous engine . I have a ld4b on it now.
 
This a 65 dart charger 273 commando I had a few years ago I told you all about that would rev to 7000 rpm all day long. Here is a video of it . I recall it revved to 6500 rpm on one of these hits after I hit the secondaries . She smoked bad but did it go. LOL I trimmed the video because it was too long and now the sound doesn't match the movements in time. you get the idea though.trimmed smoking bad reving
 
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Finally got the fish out of storage . I checked the compression on the commando with a new gauge and it is 150 + - a couple . Good thing.......... I've been running 93 octane . probally some where around 10.1 compression .
 
Finally got the fish out of storage . I checked the compression on the commando with a new gauge and it is 150 + - a couple . Good thing.......... I've been running 93 octane . probally some where around 10.1 compression .
sounds healthy.
 
VIDEO !
Update on the dynomax ultra flow mufflers I was telling you guys about .
Well they are installed and It sounds Awesome !! and throttle response is very very fast . The Drone at 35-45 mph is Gone . When you run this beast up thru the gears it really Barks Loud for sure . I love the Sound . JUST A COUPLE HALVE THROTTLE BLIPS.

 
Finally got the fish out of storage . I checked the compression on the commando with a new gauge and it is 150 + - a couple . Good thing.......... I've been running 93 octane . probally some where around 10.1 compression .
With 150-ish and a medium cam...9.3-9.5. Not unusual for Mopars to show 3/4 less point than advertised by Mopar.
 
VIDEO !
Update on the dynomax ultra flow mufflers I was telling you guys about .
Well they are installed and It sounds Awesome !! and throttle response is very very fast . The Drone at 35-45 mph is Gone . When you run this beast up thru the gears it really Barks Loud for sure . I love the Sound . JUST A COUPLE HALVE THROTTLE BLIPS.


I like the sound. I should replace the single muffler on mine. The Accurite muffler is too quiet! lol
 
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update on the old 273 build .been aleast a year .......... IT'S RUNNING GREAT ! No issues what so ever. that is one stout 273 I built ! I ran a couple friends with 360's ... one was a magnum crate 360 with 380 magnum engine duster with headers 3000 stall and 3.91 gears ... plus slicks the other was dart built 360 with cam 4000 stall and 3.91 gears ... the little 273 hung right with these guys . Now I need to put my slicks on and show them guys what a 273 can do ! since it spins thru first and second gear . lol

IMG_6233.JPG
 
Good to hear ! I have acquired some Ross 60 over pistons - minus one.....and some early Isky cam - springs and lifters....these were purchased for a 273 build on a 1967 Cuda that never happened. Hope to get another piston from Ross and build the original motor that was in my 1965 Formula S.
 
update .... update
My 273 commando is still running strong . seems to get fast and faster every year with more miles put on it .
I tried tweaking a couple afb carbs for more power but the one carb that really turned the 273 commando on , was a holley dp 700 carb . It just loved it in All rpm ranges . I jetted down a couple sizes on each end and it loved it . throttle response is awesome and the top end power pull is just a rush. it screams ! haven't taken it over 5900 rpms yet , cam peak power is 6400 rpms . just keeping it there so the engine last longer .
 
update .... update
My 273 commando is still running strong . seems to get fast and faster every year with more miles put on it .
I tried tweaking a couple afb carbs for more power but the one carb that really turned the 273 commando on , was a holley dp 700 carb . It just loved it in All rpm ranges . I jetted down a couple sizes on each end and it loved it . throttle response is awesome and the top end power pull is just a rush. it screams ! haven't taken it over 5900 rpms yet , cam peak power is 6400 rpms . just keeping it there so the engine last longer .
one more thing added is another pair of firestone tires to the rear. lol
 
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