67' Barracuda 273 (Camshaft Results at the Track)

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Great info i cant wait until you try that Norris type cam shaft (5) as its pretty much the same as the comp cams 270s specs are
RPM Range:1800-5800 Valve Lash:0.022 EX-IN Valve Timing:0.006 , Duration:270, Lobe Separation: 110, Duration @ .050" Lift:224-224, Intake Centerline:106, Valve Lift:0.468-0.468, Lobe Lift:0.313 , Valve Timing @ 0.006 Lift: Exhaust Closes 21 ATDC Opens 69 BBDC 106% Intake 29 Opens BTDC
61 Closes ABDC
 
Great info i cant wait until you try that Norris type cam shaft (5) as its pretty much the same as the comp cams 270s specs are
RPM Range:1800-5800 Valve Lash:0.022 EX-IN Valve Timing:0.006 , Duration:270, Lobe Separation: 110, Duration @ .050" Lift:224-224, Intake Centerline:106, Valve Lift:0.468-0.468, Lobe Lift:0.313 , Valve Timing @ 0.006 Lift: Exhaust Closes 21 ATDC Opens 69 BBDC 106% Intake 29 Opens BTDC
61 Closes ABDC


x2. I have the Comp Cam 270s (part# 20-246-4) in my 273. No dyno tests yet, will be done this summer.

Djakken
 
This #4 Camshaft (Crane SBM-273 'Off-Road') has a strong Mid-Range Torque Level
with a Range of (2000 to 6000 RPM's).

(.446/.467 Lift ~ 288*/298* Duration ~ 110* LSA ~ 106* CL}

This Camshaft was very popular in the late-60's and early-70's for the Mopar 273
and 318 build-ups. Regarded as a 'Performance Camshaft' with a 'choppy idle'.

Not sure if it will provide a High-RPM Horsepower gain than the previous Crower Camshaft.

The Camshaft is going in today. The Valve Springs are still the #250 lb. 'Load-Rate' units.

I'm guessing the Horsepower Level will be identical to the previous (#3 Camshaft) but the
Torque will be greater between 3000 and 5000 RPM's.

Not sure what to expect on the 'Accelerated Timing Test'.
 
Camshaft #4 is in.....

Engine sounds like a 'monster' from 2500 thru 5600 RPM's.

This Camshaft is designed to kick in at the Upper Bottom-End and Pull Strong thru Mid-Range
and into the Early Top-End.

An excellent Camshaft for Moderately Modified Street or Mild Race Applications.
Requires;
* Headers
* Mild Cylinder Head Work
* Carburetor Up-grade
* Performance Intake
* 9.5 to 10.5 Compression Ratio
* Gears (4.10 Minimum Recommended)
* 2500 Stall Converter for Automatic

Only question will be, can it improve at Top-End in the upper RPM range.
Will test in 2-days.
 
This is getting real fun! Love the old school big duration cams. tmm
 

I started with a 63’ Dart and 65’ 2 bbl 273, 904 tranny and 7 ¼ rear.

Modifications are, from front to rear.
- Aluminum 3 row radiator
- 7 blade fan
- Edelbrock D4B 4 bbl, two plain intake
- Edelbrock 1406, 600 cfm carb
- 10.5 to 1 pistons
- Comp Cam 270 s
- New bearings
- New valve springs (don’t remember the load)
- Spitfire headers
- Electronic ignition, Procomp Electronics
- Front disc brakes, K-H
- 8 ¾ rear end with 3.23 gear and Sure Grip

The modification was done last winter, and during the summer 2012 it was easy driving.
Have made some tests the last weeks and as I see it power comes above 2000 – 2500 RPM. From 2500 to 5000 RPM it’s a rocket.

Djakken
 
* Camshaft Upgrade #5 ~ Norris Camshaft = .466 / .466 Lift ~ 270* / 270* Duration = {304 HP} = 12.77 @ 106.52 MPH

* Camshaft Upgrade #4 ~ Crane Camshaft = .446 / .467 Lift ~ 288* / 298 * Duration = {303 HP} = 12.72 @ 105.72 MPH

* Camshaft Upgrade #3 ~ Crower Camshaft = .447 / .447 Lift ~ 268* / 272* Duration = {299 HP} = 12.80 @ 106.86 MPH

* Camshaft Upgrade #2 ~ General Kinetics = .435 /. 441 Lift ~ 282* / 282* Duration = {294 HP} = 12.87 @ 106.45 MPH

* Camshaft Upgrade #1 ~ Camcraft Camshaft = .440 / .440 Lift ~ 260* / 260* Duartion = (280 HP) = 13.04 @ 104.97 MPH
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Camshaft #5 ('Norris 273 Race' - '1969 Profile') has a suprisingly smooth idle. It pulled well in 1st Gear, and had a steady pull right up to High RPM's (5700). Peaked at the end of each gear shift in 3rd and 4th.

It is a 'snappy bumpstick', and is a good camshaft for Moderate Steet / Mild Race Applications.
 
* Camshaft Upgrade #4 ~ Crane Camshaft = .446 / .467 Lift ~ 288* / 298 * Duration = {303 HP} = 12.72 @ 105.72 MPH

* Camshaft Upgrade #3 ~ Crower Camshaft = .447 / .447 Lift ~ 268* / 272* Duration = {299 HP} = 12.80 @ 106.86 MPH

* Camshaft Upgrade #2 ~ General Kinetics = .435 /. 441 Lift ~ 282* / 282* Duration = {294 HP} = 12.87 @ 106.45 MPH

* Camshaft Upgrade #1 ~ Camcraft Camshaft = .440 / .440 Lift ~ 260* / 260* Duartion = (280 HP) = 13.04 @ 104.97 MPH
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Camshaft #4 = Excellent Torque (2200 RPM thru 5500 RPM). Pulled well at Upper Bottom-End and stayed Strong
all thru Mid-Range and into Early Top-End. Faded at Mid-Range of Top-End and High RPM's.

Gained +4 HP over Camshaft #3, lowered Elapsed Time by {-.08}.

What is interesting to me is how the smaller #3 Crower is hanging in with the bigger #2 and #4 cams.

Are you running this motor every cam change on an engine dyno AND then ALSO running it at the track? If so, wow you are putting a lot of effort into this. Very cool!

Seems you are getting a perfect .07 to .08 ET improvement every swap. Tough to do with so many variables and get perfect consistant results like that. Congrats!
 
I started with a 63’ Dart and 65’ 2 bbl 273, 904 tranny and 7 ¼ rear.

Modifications are, from front to rear.
- Aluminum 3 row radiator
- 7 blade fan
- Edelbrock D4B 4 bbl, two plain intake
- Edelbrock 1406, 600 cfm carb
- 10.5 to 1 pistons
- Comp Cam 270 s
- New bearings
- New valve springs (don’t remember the load)
- Spitfire headers
- Electronic ignition, Procomp Electronics
- Front disc brakes, K-H
- 8 ¾ rear end with 3.23 gear and Sure Grip

The modification was done last winter, and during the summer 2012 it was easy driving.
Have made some tests the last weeks and as I see it power comes above 2000 – 2500 RPM. From 2500 to 5000 RPM it’s a rocket.

Djakken
Thanks for your info my setup will be very close to yours i have the 10.5 pistons 40 up,comp cams pro magnums rollers,push rods,270s cam, solid lifters,valve springs (singles with dampeners)c/cams 7 degrees retainers with locks, Ferrea 6000 stainless valves,Heads all machined new seats with k line guides and ports all bowl ported.Have the Edelbrock LD4B with Eddy 1406 carb vac sec.All new bearings,HV oil pump,new pick up.I went for the scat I beam forged 4340 rods as it would of cost nearly as much getting my originals resized with new Arp rod bolts.New powerforce + 7.5 harmonic balancer,c/cams timming chain with MP chain tensioner.Milodon lifter baffle as well as windage tray.At the moment im using the HEI Dizzy but im favouring the MSD E curve.Running the A904 but it to will get a freshen up,i have purchased the full rebuild it with steel plates , kevlar bands,Transgo shift kit.3.55 rear.Some here might say why waste your time doing all this with a 273 as they are too expensive not enough cubes, etc i say thats why because they're aint alot of them.I just like being a little different!
 
Auto-X-Cuda,

Yes, we are keeping everythinhg the same, except the Camshaft changes.

Car is put on an old Bear Chassis Dyno, that has been upgraded. We dial
everything in, so we don't waste time during pre-accelerated timing tests.

We run the car on an auxilary road, set up with a timing system.

I know, the #3 Camshaft (Crower Camshaft) surprised us too, that is why
we are performing accelerated timing tests.

The complete results of this Camshaft Test will be in a Performance Magazine
this Spring.

Going for #5 next.
 
Mr. Commando,

Camshaft #5 is a 'Norris Camshaft', which was called a '273 Race' back in 1969.
.466 Lift and 270* Duration, with a 110* LSA and 106" Center-Line.
The Valve-Lash is .018 /. 022

We will still be using the #250 lb. (with valve open) Valves Springs. This Camshaft
should pull well up to 6000 RPM's.

According to the literature (from 1969), this Camshaft is supposed to have
Good Upper-Range Bottom-End Torque and Top-End Power.
 
Not surprised ,by the Crower.Worked, for a Crower dealer,for a long time .They like ,mellow lobes, wide lca's ,split patterns ,for s.b.Mopars. Crower,is mopar favored.
 
very very cool!!! wonder how the edelbrock performer RPM cam would work out. it's sort of an old school cam no one likes anymore. lol
 
Not surprised ,by the Crower.Worked, for a Crower dealer,for a long time .They like ,mellow lobes, wide lca's ,split patterns ,for s.b.Mopars. Crower,is mopar favored.

Correct,

The Small Block Mopar and Crower Cams had a liking. Not surprised
by the way the Camshaft #2 (Crower .447 Lift) performed.

A few others that we had, but lost over the years was,
* Racer Rrown - ST ?
* Isky - ?
* Crane - 'Compu Cam'

This 273 really likes the J.E. Lightweight 10.5 Compression Pistons and
Childs & Albert Rings.

Connecting Rods are 'Valley Machine' units. Which are nothing more than
'stock 273 skinny units' that have been shot peened, reconditioned by a Sunnen
LBB-1810 Power-Stroke, and ARP Bolts. A small oil-hole has been drilled
into the top of the rod (pin boss).

The rails of the connecting rod have been ground down and have been smoothed
and polished, along with the top piston pin end. Absolutely no problem handling
High RPM's.

These units are as light as a 'butterfly'.
 
It would be interesting to see how the duration at 0.050" lift numbers compare.
 
It would be interesting to see how the duration at 0.050" lift numbers compare.

Specks,,,,

Unfortunately we do not have those 'exact' numbers off of the early
Camshafts.

The Norris '273 Race' we have..
.466 Intake / .466 Exhaust...{Lift}
270* / 270*..................... {Duration}
224* / 224* @ .050
110* LSA
106* CL
 
Great stuff, thanks for sharing. Will any of these cam and lifters be for sale when your done?
 
1970 LA,,,

Never was asked that question. Though we've had some of these Camshafts for over 40 years
(Boxed and coated with Grease}

Camshaft #5 Installed.
.466 / .466 Lift ~ 270* / 270* Duration.

Horsepower at 304 HP, but the Torque Level was lower than Camshaft #3 which had a profile of
{.446 / .467 Lift ~ 288* / 298*}

Still going with #250 lb. rated Valve Springs.

This 'Norris 273 Race' has a suprisingly 'smooth idle', but snaps power nicely above 2000 RPM's.

Will 'Test Run' tomorrow.
 
Thanks for taking the time to test,true dedication to the project.
 
69 cuda 440 great info and its terrific you have made the time to run these camshafts with power outputs'
Thank you for your all your time and effort, very valuable info for us 273 guys who refuse to bend to the 4 inch bore stroker engine masses.Cheers!
 
Thanks to all who have added their compliments.

The one issue here is, that the Stock #2658920 Cylinder Heads are difficult to get
higher Horsepower numbers because of the Small Ports and Small Valves.

Usually, these heads are good up to a range of "300 to 315 HP".

They have not been ported, but have a 'High-Pro' Competition Valve Job and
gasket-matched ports.
 
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