273 cam

[AJ/FormS]

Aj that must have been an ENGLE they use .008 which is close to what MP would be if they measured duration by lifter rise- but they don't
they take it off the blueprint starting where there clearance ramp meets the acceleration ramp
The stock 440 magnum cam is like 310 SAE (004)
toolguy Comp Cams and Isky are not exactly cheap and certainly not a good value in a Mopar XE-HL exceptred to bad they do not make a complete line
and no one in their right mind would custom grind of the lobe list

Hang on W
I came to the same conclusion about it being an Engle.
As for the rest I'm gonna need an interpreter,lol.
Here's all I got since I did not degree the advertised to verify.
I have had the 2430 and currently in the engine is the 3038
Across the top, column 5; it says "at .008 lift". We might need an interpreter for that too,lol.

#6---Older Camshaft Profiles (Small Block Hydraulic: HE Series)

 

[Wyrmrider]

Oldies but goodies AJ
Here is the next size smaller from Chet Herbert for Ford or larger not chevy
Cat 2E 255-260 200-205 425/450 remember Herbert adv is at .005
CLE2N 265/275 205/215 425/455 cam posted above
Here is the next larger 280 .005 series from the from Chet Herbert
Cat 4B 280-300 225-240 480-495 chevy profile
Cat 4D 285-300 230-240 500-500 Ford profile
Cat 4A 285-300 230-240 511-510 Mopar Profile
chevy 285 235 500 race profile chevy .500 lift to work with then available springs same in and ex for easy setup
chevy 295 245 500 street/strip
chevy 300 240 500 street/strip
Chevy 5W 295-305 240/240 550/550 very short ramps special springs (essentially a solid cam where hyd lifters required hyd lifters set at .001)
Way back when not only did have separate profiles for the three lifter sizes he had separate profiles for intake and exhaust
something most other cam grinders - married to their high production automated grinders, have not felt the need to do
well they run sorta ok so I guess that's good enough
BTW (Isky HL .007 Megacam .007 opening ramp- .010 closing ramp- have fun comparing that one- long closing ramp on Megacam .010 hides
one nice thing about Cam Doc is that it gives you cam AREA

 

[273 ball]

I pm'd him and no answer. I think we scared him off!

Hi ok what cam would be a good choice for a 8.8 to 1 compression 2 barrel stock . 273 anything from summit. tyler

 

[AJ/FormS]

For sure 8.8,Tyler
And WHY
does it have to be a Summit?

 

[C130 Chief]

Tyler, if you plan to keep the 2 Bbl carb and intake, and it both of your posts indicate you do, the factory 360 cam would be a good choice. Sealed Power CS665. Affordable.

My advice would be to leave the engine alone if it runs until you an find a 4 Bbl intake manifold and carb. If your engine is a 1964 or 1965, you have a different bolt angle and would need either a factory iron intake (cheap) or an Edelbrock D4B (getting hard to find, and people want too much $$$). A 500 Edelbrock, or Holley 600 vacuum secondary carb would be fine.

The next thing to improve would be the exhaust. The 273 exhaust was, to put it kindly, terrible.

 

[pishta]

I crewed for Lefty in the early 60's RIP
Chet had some good MOPAR cams- most not in the catalog- most you had/have to ask for

funny you should mention that because Chet himself recommended that (?) cam, and I'm not sure that was even the cam he sold me knowing that he had some unpublished grinds. I told "the old guy in the wheelchair" what I had and he handed me the cam. I didnt realize that was ol' Chet until years later when I was talking to a guy at a show!

 

[273 ball]

For sure 8.8,Tyler
And WHY
does it have to be a Summit?

Hi it dosent have to be summit .

 

[Wyrmrider]

Lunati Voodoo
454,lift,.302 lobe 253@.006 208 @50
454/454 253/258 208/213 112/108 EFI OK Lunati Voodoo idle 5000

Engle
K-52HYD.458" .305" 254° 209° more seat than Lunati
Mopar Performance
DC .410/.425 248/256 202/202 113 211/218@.050 110lca
Bullit .
Lift lobe .006 .050 .200
.405 (.2700) 239 189 102 HC239/270 shortest Bullet

.432 .288 249 201 115 HC249/288

.433 288 254 206 120
.432 2880) 254 201 120 Bullet CTA conventional asymmetrical torque grind

.461 .307 lobe 254 202 120 Jones special @.275 lobe lift Jones is 64 when DC 260 is 42

“Unlike some of the other company's chrysler cams, this profile is designed to take advantage of the chrysler's .904" lifter.
.307 lobe lift Part# HD64307-112 Comparing to Crane this cam is much shorter on the seat timing at .004 246
is the best choice for low compression with lots of lift
next best is the Howard below


.479/494 255/261 208/214 110/106 LA 1400-4800 Howard Torque winner : 711381-10

"about as big as you want with stock converter."


Crane H-202/2880 420 260 202 113@.200 shortest Crane .904 H2 series

Low budget Crap with long flanks that would not shut the door quickly for your low compression build
several brands have same cam Note the difference with the Crane which is directly comparable at .004 /SAE spec
SP CS1006R 420 278 sae 204 114lca

SP CS 1098R 420/443 278/288SAE 204/214 112 lca ( Edelbrock performer (sic))

Sealed Power 360 cam sorry really late intake close would kill him with no compression- two shown above are the best of a bad lot

want a solid I can see what I can find but I can say unequivocally Comp Has NOTHING that fits your needs
I'd first call Mike Jones - let Mike pick the exhaust lobe and if He's busy Howard or Bullet- they have lots of choices
shelf cam Lunati Voodoo (only) or Howard- see above

 

[nm9stheham]

Wyrm, you got me to looking..... at the Crane solid flat tappet profiles and I see one that is the F11 series for .904 tappets:
F228/3334
264* duration at .020" lobe lift, and 140* duration at .200 lobe lift
What I can't do is to 'translate' that from solid tappet lifts to hydraulic tappet lifts. If valve lash is .025" clearance, then true 'advertised duration' on the seat will be well under 260, but how to equate it to a .200" lift for a hydraulic? Is there a general "lift per degree of crank rotation" number that can be applied, or is that all over the map?

 

[Wyrmrider]

all over the map
at least they are using .020 which is sort of a standard
except when it's not
30-30 vs tight lash really compounds
Bullet has a full line, Jones has some, Engle, Comp has nothing as do several other big grinders- sad
appreciate you and AJ helping these low compression builds

 

[toolmanmike]

Hi will a tumper cam work on a 273 2 barrel motor

Did you guys forget why we are here?

 

[moper]

They just like hearing themselves type....lol.

 

[Bighead440]

I suggested the 270S Comp cam because it will run better than that "sound generating" Thumpr cam in the 273, which should already have adjustable valve gear. Using the hydraulic Thumpr will require pushrod/rocker changes ($$$) as well. I don't think "aggressive" lobes or "area under the curve" are really the OP's concern. Good sound, long life and driveability probably ARE.

 

[nm9stheham]

Later 273's have hydraulic lifters and the stamped rockers... so we don't know at all if a solid lifter cam, or the thumpr or any other hydraulic lifter cam, will drop right in or not.

 

[nm9stheham]

As for tangential conversations/comments, refer to posts #44 & #50. It's gonna happen on the internet.....

 

[Bighead440]

Later 273's have hydraulic lifters and the stamped rockers... so we don't know at all if a solid lifter cam, or the thumpr or any other hydraulic lifter cam, will drop right in or not.

The OP does need to provide more info. I am fully aware of the late 273's being hydro-cammed, and the early 273's having the odd intake bolt angle, but I have personally never seen a 273 that WASN'T solid lifter equipped. If it has hydraulic valve gear, I still wouldn't use the Thumpr in that application, my .02c worth.

 

[nm9stheham]

Got parts of a '68 273 in the garage that was built with the hydraulic valve gear. Totally agree on the thumpr.... as has been said, it is for the noise, not the 'go'.

 

[Bighead440]

Got parts of a '68 273 in the garage that was built with the hydraulic valve gear. Totally agree on the thumpr.... as has been said, it is for the noise, not the 'go'.

The only "273" that I thought was hydraulic equipped turned out to be a transplanted 318 (in a '69 Dart, which was the last year for 273's I believe). Single plane 2bbl. iron intake, plug wire loom valve covers and all...

 

[toolmanmike]

68 and 69's were hydraulic.

 

[nm9stheham]

To the OP: All these questions of the valve gear being hydraulic or solid cam makes a difference in the cam selection being discussed.

Can you take off a valve cover and look, and let us know what you find?

If hydraulic, the rockers will look like in this thread:
318, wrong rocker arms?

If solid, then the rockers will look like in this thread (you may have to click on the image files to see the pix):
273 rockers? on 340

 

[AJ/FormS]

69s for sure in Canada