273 hp specs

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Dakota_Don

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what are the 273 hipo engine specs?

real CR

and real crank HP

camshaft specs

ect..


thanks
 
A search found the following H.P. information at http://en.wikipedia.org/wiki/Chrysler_LA_engine#273_V8

273 V8
The 273 (4.5 L) was the first LA engine, introduced in 1964 and offered through 1969, rated at 180 BHp. It had a 3.625 in (92 mm) bore and 3.31 in (84 mm) stroke. It had a mechanical solid lifter valvetrain until 1968 when hydraulic lifters were introduced. A special version was also available in 1966 only - it used a 0.500-inch (12.7 mm) lift solid-lifter camshaft, fabricated-steel-tube exhaust, and a Holley 4-barrel carburetor, producing 275 horsepower (1 hp/cu in). It was available in the Dodge Dart only, and the car so equipped was called the "D-Dart". A 235 hp (175 kW) version with a less aggressive camshaft and without the tube headers was available on regular production Darts, Valiants, and Barracudas from 1965 to '67, it was standard only in the Barracuda Formula S model.
 
hi, the hipo 273, 235 hp rated, 10.5 cr , solid lifter, 248/248 dur, .425 lift, 48 deg overlap,carter afb.single springs, dual point dist. actual hp, probably about 200. just food for thought.
 
There are two different 273 HiPo motors. One was a regular production option from 1965 to 1967. These were known as the Commando 273 in Plymouths and the Charger 273 in the Dart. They were available with either automatic or 4-speed transmissions.

The other HiPo was the D/Dart model of 1966. While the D/Dart was a separate model, Mopar offered the parts to retrofit a Commando or Charger 273 to D/Dart specs. The D/Dart model came only with a 4-speed and had a 4.86:1 8.75" rear

......................Charger/Commando................D/Dart
Horsepower...... 235 @ 5200 ......................275 @ N/A
Torque............ 280 @ 4000 ...........................N/A
Camshaft I .......... .425" .............................. .495"
E ....................... .425"............................... .505"
Duration ................248º............................... 284º
Overlap ..................46º .................................N/A
Carburetor..... 625 cfm AFB....................... 750 cfm Holley
Exhaust........ cast iron manifolds............... headers by Doug
Warranty........5 yr/50,000 miles...................... NONE

Dick Maxwell was the staff engineer on the D/Dart program.
 
2 Darts said:
There are two different 273 HiPo motors. One was a regular production option from 1965 to 1967. These were known as the Commando 273 in Plymouths and the Charger 273 in the Dart. They were available with either automatic or 4-speed transmissions.

The other HiPo was the D/Dart model of 1966. While the D/Dart was a separate model, Mopar offered the parts to retrofit a Commando or Charger 273 to D/Dart specs. The D/Dart model came only with a 4-speed and had a 4.86:1 8.75" rear

......................Charger/Commando................D/Dart
Horsepower...... 235 @ 5200 ......................275 @ N/A
Torque............ 280 @ 4000 ...........................N/A
Camshaft I .......... .425" .............................. .495"
E ....................... .425"............................... .505"
Duration ................248º............................... 284º
Overlap ..................46º .................................N/A
Carburetor..... 625 cfm AFB....................... 750 cfm Holley
Exhaust........ cast iron manifolds............... headers by Doug
Warranty........5 yr/50,000 miles...................... NONE

Dick Maxwell was the staff engineer on the D/Dart program.
Click to expand...


thank you, the D dart is what i wanted
 
Nice post, I have an old national service data boo that list all the cam specs, i think they were racer brown, and the solid lifter cam had I recall 70 degrees overlap, poor lowend, but above 3500 woke up good.

I built this motor back in the mid 70s, had custom pistons I went 11:0 and a little larger lift too. Well and tweaked the heads before I then went next step and noticed the block for larger valves etc.

Well I also recall the valve srings were monsters for the little 273, something like 185lbs seat pressure valve closed.

Amazine how years later they only gave a 340 a 275 hp rating. We know that was fake with beter exh, more cubes, and much better heads can etc..
 
Hey I'm trying to figure out what I have stock so I can run a compressor calculator and make sure I get the right parts and not screw up my compressor ratio.

My 66 273 got a bore years before a got it and should be .04 over bore.

I believe the following is right:
bore is 3.665" (3.630 stock)
Stroke 3.310 (stock)
Volume 35.014 cubic in (34.256 stock)
Displacement 280.112 (274.048 stock)
*I got the stock form"how to rebuild the small block mopar" book by SA designs.

To do this math I also need:
Deck clearance - ?
(Deck height is 9.6")

Dome or dish measurements?
Dish I believe but not sure how much

Head gasket height
.39" for summit 1008 (stock .010 apparently?)

Head gasket diameter
4.180"

Stock compression should be 8.8:1 when I run the math, but I'm not getting that.

If anyone has there numbers or sees errors in what I have. Please let me know.
 
ValiantRacing said:
Stock cam per NHRA is .415/.425 lift
Click to expand...
Ok, I've not rebuild the top end of a motor before so I'm not sure what todo with that info, but thank you in advance for future reference.

I am currently trying to get the stock specs to fill out a compression calculator, and I believe I need most of the info I listed about and stock it should show 8.8:1 compression ratio. However information has some key gaps and contradictories.

If anyone can show me the stock 273 specs that equal 8.8:1 in a compression calculator I would be greatful and will be able to compair aftermarket heads and ensure I keep the compression I have or improve upon it.

Thanks
 
Deck clearance is not always the same and varies. You need to take your own measurement there. I've seen some mopar engines more than 0.100 in the hole and some close 0.020 in the hole. When I rebuilt mine, I don't even remember what it was.

Attaching the pages from the 65 TSM. I recall the 66 TSM could be downloaded at one time but don't have a link for that.
20230412_155310.jpg


20230412_155348.jpg

I believe Pistons would be flat top or dome'd. If someone put dished in there when they rebuilt it, not sure why they wouldda done that. I'd use Dish volume =0 if not a high compression 273.
 
chewy said:
Deck clearance is not always the same and varies. You need to take your own measurement there. I've seen some mopar engines more than 0.100 in the hole and some close 0.020 in the hole. When I rebuilt mine, I don't even remember what it was.

Attaching the pages from the 65 TSM. I recall the 66 TSM could be downloaded at one time but don't have a link for that.
View attachment 1716076848

View attachment 1716076849
I believe Pistons would be flat top or dome'd. If someone put dished in there when they rebuilt it, not sure why they wouldda done that. I'd use Dish volume =0 if not a high compression 273.
Click to expand...
Sir, I greatly appreciate the info sir!

Is there a way to get deck clearance without pulling the motor apart?
 
RioGrandMan said:
Sir, I greatly appreciate the info sir!

Is there a way to get deck clearance without pulling the motor apart?
Click to expand...
Deck clearance? What are we talking about here?
RioGrandMan said:
Hey I'm trying to figure out what I have stock so I can run a compressor calculator and make sure I get the right parts and not screw up my compressor ratio.

My 66 273 got a bore years before a got it and should be .04 over bore.

I believe the following is right:
bore is 3.665" (3.630 stock)
Stroke 3.310 (stock)
Volume 35.014 cubic in (34.256 stock)
Displacement 280.112 (274.048 stock)
*I got the stock form"how to rebuild the small block mopar" book by SA designs.

To do this math I also need:
Deck clearance - ?
(Deck height is 9.6")

Dome or dish measurements?
Dish I believe but not sure how much

Head gasket height
.39" for summit 1008 (stock .010 apparently?)

Head gasket diameter
4.180"

Stock compression should be 8.8:1 when I run the math, but I'm not getting that.

If anyone has there numbers or sees errors in what I have. Please let me know.
Click to expand...
It sounds like you are fairly certain about the .040 overbore but what pistons were used? I would pull a plug and get a borescope for a peek inside.
 
toolmanmike said:
Deck clearance? What are we talking about here?

It sounds like you are fairly certain about the .040 overbore but what pistons were used? I would pull a plug and get a borescope for a peek inside.
Click to expand...
The deck clearance is needed in most of the compression calculators online. It's how far above or below the block the piston spots at TDC.
 
Most 273 pistons are .020 to .030 in the hole. No such thing as a dished 273 piston. High Performance 273 pistons had a dome and were 10.5:1 with the right head gasket. 265 hp with flat top pistons and an Isky E-4 solid cam and 920 heads, machine work done right.
 
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