67' Barracuda 273 (Camshaft Results at the Track)

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69 Cuda 440

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1967 Barracuda '273 Commando' (Fastback 4-Speed)

Car Weight #2975 lbs. (w/o Driver)

273 (+.040) with JE Lightweight Pistons (10.5 - 1 Compression) (Old School)
#2658920 Cylinder Heads (Competition Valve Job and Gasket/Port Matched)
Valves = 1.78 Intake / 1.50" Exhaust
Combustion Chamber 57.3 CC's.

We found an old (still in the box) General Kinetics #A6M-282-R Camshaft
in our storage facility, and decided to give it a try since it was still in the box (brand new and never used).

Specs
Lift --------.435 Intake / .441 Exhaust
Duration --- 282* / 282*
Lobe ------ 110*
Centerline - 106*
Lash ------ .018 Intake / .030 Exhaust

Car Performance = 12.87 @ 106.45 MPH
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Previous Best = 13.04 @ 104.97 MPH

With Camshaft = Camcraft (273 Marine Performance)
Lift -------- .440 Intake / .440 Exhaust
Duration ---- 260* / 260*
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Note; The 'old' General Kintetics Camshaft (old profile) increased Horsepower (+14 HP)
over the Camcraft '273 Marine Camshaft'.

The 273 Commando is now putting out 294 Horsepower @ 5750 RPM's.

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Next Results To Be Posted
 
Sweet !!! Nice to see the results !! How are the torque numbers ?
 
Nice run. What are you hoping to get the car down to?

Ted and Ralph both commented that the 1966 Barracuda would have been a better car to run the D/Dart engine in because of the added weight of the backglass over the rear wheels.
 
Forget to mention a few other Items.

Valve Springs (Crower #68305X1) = (Valve Closed; #95 Lbs. @ 1.65") and (Valve Open; #250 lbs. @ 1.20")
Stock Rocker Arms
Chromed Rocker Shafts
Balanced Internals
Hooker Headers (Competition = 1/5/8" Primary x 34" Length x 8" Collector with 3" Outlet)
Stock Cast Iron Intake (Gasket-Port Matched with Secondary Throttle Bore Opening, Opened to 1 11/16")
Carburetor = Carter AFB 600 CFM #3447 (From the 1963 426 Max-Wedge Stage I)


Next Camshaft, and old (still in the box) Crower Cam #268-M from 1969.
Lift........... .447 Intake / .447 Exhaust
Duration.... 268* / 272*
Lobe......... 110*
Centerline.. 108*
Lash......... .018" Intake / .024 Exhaust

Make the Camshaft switch tomorrow, then we'll see where the Horsepower Results are,
and then back to an accelerated time test at the track later.

This is the 'true way' to test performance modifications with factual results, not
paper results.
 
i'll bet money that the Mopar Performance purple .528/.528 will be the best performing with stock manifolds, if you happen to test that.

AndyF did a bunch of testing with big blocks using stock manifolds and the .528 solid lifter was optimal.
 
Big difference between big block and a 273.
 
well interestingly, the D-Dart racing package in '66 had a camshaft about like this:
284deg duration .495/.505 intake exhaust
 
Great results and info. Thanks for posting 440. What rear gear ratio are you running?

Oldschoolcuda
 
Honest Injun,

All 'Old School Stuff'

* 4.89 Gears
* Super/Stock Springs
* Coletti Pinion Snubber (1970 Model)
* Drag Shocks (Old School with 50/50 Rear)
* Front Shocks (Worn out units from a 1967 6-Cylinder Valiant)
* Front Torsion Bars .850" (273 2-Barrel non-Formula S)
* Slicks (M & H Racemaster) 9.00" x 14" x 28" Diameter (Height)
* Ed Hamburger Oil Pan (7 Quart)
* American Racing Wheels (5-Spoke Polished) (14" x 6" Front) and (14" x 7" Rear)
 
Awesome.Thanks for info. Figured you had some decent gear. Looking forward to results with the crower.

Oldschoolcuda
 
Thanks for the compliments gentleman,

Since we had accumulated alot of parts over the years, and stored
the components, we figured to give the 'Old School Stuff' a fair shot.

Funny, back in the day (1968/1969) the Crower 268-M (Mechanical Camshaft)
.447 Lift and 268* Duration was considered 'Moderate Radical'.

I think the Camshaft was listed as 'Very Rough Idle, Not Recommended For Street Use'
 
Crower Camshaft was put in.

Engine is a bit stronger above 5000 RPM's.

Based on calculations, should be close to 300 Horsepower (A gain of +5 HP over the General Kinetics Camshaft).

* Camshaft Upgrade #3 ~ Crower Camshaft = .447 / .447 Lift ~ 268* / 272* Duration = (299 Horsepower) = 12.80 @ 106.86 MPH

* Camshaft Upgrade #2 ~ General Kinetics = .435 / .441 Lift ~ 282* / 282* Duration = (294 Horsepower) = 12.87 @ 106.45 MPH

* Base Starting Point #1 ~ Camcraft Camshaft = .440 / .440 Lift ~ 260* / 260* Duration = (280 Horsepower) = 13.04 @ 104.97 MPH
 
69 Cuda 440 said:
Crower Camshaft was put in.

Engine is a bit stronger above 5000 RPM's with Camshaft {#3}.

Based on calculations, should be close to 300 Horsepower (A gain of +5 HP over the General Kinetics Camshaft).
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* Camshaft Upgrade #3 ~ Crower Camshaft = .447 / .447 Lift ~ 268* / 272* Duration = (299 Horsepower) = 12.80 @ 106.86 MPH

* Camshaft Upgrade #2 ~ General Kinetics = .435 / .441 Lift ~ 282* / 282* Duration = (294 Horsepower) = 12.87 @ 106.45 MPH

* Base Starting Point #1 ~ Camcraft Camshaft = .440 / .440 Lift ~ 260* / 260* Duration = (280 Horsepower) = 13.04 @ 104.97 MPH
Click to expand...
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Camshaft #3 (Crower) = Was responsive at Mid-Range and pulled well at early Top-End, before hitting peak.

Camshaft #2 (General Kinetics) = Very strong Mid-Range Torque. Flattened out at High RPM's.

Camshaft #1 (Camcraft) = A good 'Steady-Eddie'. Steady pull at Low-End and Mid-Range. Flattened in higher RPM's.
 
Magno,,,,

The Test Results are put together for a magazine article.

The other Camshaft units that will tested

{#4} .446 / .467 Lift ~ 288* / 298* Duration
Cam = Crane 'Dual-Pattern' SBM Off-Road (1972 Model) (Good Mid-Range Torque)
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{#5} .466 /. 466 Lift ~ 270* / 270* Duration ~ 110* LSA / 106" CL
Cam = 'Norris 273-Race' (1969 Model) (Lopey Idle = 2000 - 6000 RPM Range)
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{#6} .477 / .477 Lift ~ 280* / 280* Duration ~ 112" LSA
Cam = 'Crower 300' (1971 Model)
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{#7} .477 / .480 Lift ~ 268* / 280* Duration ~ 110* LSA / 106* CL
Cam = 'Compu-Cam XE-268' (Range = 1600 - 5800 RPM)
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{#8} .488 / .488 Lift ~ 268* / 274* Duration ~ 110* LSA
Cam = 'Crane Cam Zip-488' (Strong Mid-Range = 2000 - 6000 RPM)
------------------------------------------------------------------------
{#9} .510 / .510 Lift ~ 310* / 310* Duration ~ 112* LSA
Cam = 'Crane Cam Zip-510' (High RPM and Strong Mid-to-Upper Range Power)
------------------------------------------------------------------------
{#10} = .493 / .503 Lift ~ 284* / 284* Duration ~ 60* Overlap
Cam - Camcraft P820-B 'D-Dart' (1966 Model) (High RPM - Mid-Upper Horsepower Range)
-------------------------------------------------------------------------
{#11} = .504 / .515 Lift ~ 288* / 288* Duration
Cam = Camcraft P820-Bx 'D-Dart' Optimal Race (1967 Model) (High RPM - High Horsepower)
-------------------------------------------------------------------------
{#12} = .480 /.480 Lift ~ 294* / 294* Duration ~ 76* Overlap
Cam = Racer Brown ST-12 (High RPM - High Horsepower 6500 RM)
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{#13} = .505 / .505 Lift ~ 320* / 320" Duration ~ 108* Overlap
Cam = Iskendarian 505-C (High RPM - Radical Race)
 
Great thread, I enjoy seeing people run 273's, and backed behind with a four speed definitely gets my two thumbs up
 
Thanks for a great thread. I'm really looking forward to the results and to compare with my own 273 build.
 
When i was 16-17 years old I had two different 273's in a 66' Dart, at the time I had an automatic and modest gears (and budget) but both engines ran great and took a pounding. Although mine only went low 15's, it was still alot of fun and I plan to build a 273 again in the near future for one of my A-body stick shift cars to do some local bracket racing.
3.63 Bore with a 3.31 stroke, and a 6.123 rod makes a real small block, but really its gotta have solid lifters!
 
Great thread ...... When do you think that you'll get to cams #10 and #11? I'd really be interested in those. Never heard of the Bx cam. I have prints of the B.

Last week I contacted the "Other" Camcraft to see about making a D/Dart cam. For them to make a master it costs somewhere around $700. They also said that todays cam designs are much better. But they aren't a D/Dart cam! Jim at Racer Brown would make a duplicate if they had an original to make a copy from. Hint! Hint!
Alan
 
bbeep71 said:
What are you using for manifold/carb/Ign combo????
:glasses7:
Click to expand...

Thanks for everyone's interest,,,,,,,

The Intake is a 'stock' cast iron intake, with the ports gasket-matched,
and some high spots in the runners removed.

The secondary bore hole has been opened up to 1 11/16". The primary is stock size (1 7/16")
-----------------------------------------------------------------------

The Carburetor is an old Carter AFB #3447 (600 CFM) from a 1963 '426'
Max-Wedge 'Stage I'.

It has been jetted and tweaked.
-----------------------------------------------------------------------

The Distributor is a 'Ready-To-Run' Mopar Small Block #HZ-D7006 unit.

The coil is the High-Output E-Coil Super Ignition #HZ-IC2041-Red

-----------------------------------------------------------------------

Camshaft #4 is going in 'tomorrow'.

It is a Crane 'Dual-Pattern' profile (.446 / .467 Lift ~ 288* / 298* Duration) that was very popular with 'Circle Track Racers'.

I'm sure it will have 'very strong' Mid-Range Torque, but not sure if
it will pump out an increase in Horsepower at High RPM's (above 5200 RPM).

We are also installing 'new' solid lifters (Chrysler Part #2402288) which
are (-.0005) undersized 426 Hemi Lifters.

We'll see.........

It's fun using 'old school parts'....
 
Ed,

The Steel Flywheel is a 'stock' 340 (30 lbs.) unit

An old but still great Clutch Package 'Schieffer' with a '3'-Finger Pressure Plate

Fuel System, old school Carter Electro-Mech System.
 
Very cool stuff,69 440! Ought to be interesting,on those ST-12,and 505c grinds.
 
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