73jst4fun

OK, I'm down to two cam choices, is anyone using the Comp Cam extreme energy 274S mechanical lifter cam. Has 236/242 dur. @ .050 and 501/510 lift.........curious how it has performed for you....Thanks

Gordonm

Hitch

73jst4fun

Wow, tough crowd, nice guys, my friends............

See what YOU started Gordon, yeah.... buy my engine and get a good cam for it...........

L-82kid

I brought that cam but haven't used it yet. I was planning on using it with 1.6 roller rockers.

73jst4fun

Looks like that's the cam I'm going to buy..........it has good numbers for my components.......

L-82kid

whats your combo going to be?


heres mine:
357ci
pro topline alum. heads (200cc)
10.6:1 CR
rpm intake
750cfm demon carb
1.6 roller rockers (lift goes up to .535/.545)

Desktop dyno says 437hp with headers and mufflers.

73jst4fun

That's some good numbers, here's mine:

350 CI forged crank, TRW forged pistons
AFR 180 heads
10:1 CR
Air Gap manifold
650 speed demon (750 mighty demon)
1:52 magnum rollers
headers, Flowmaster 50 mufflers

This cam may be a better match for me from Comp: XS 274S Extreme Energy
lift: 5.01/.510 Dur: 236/242 mechanical lifters

Could you run these numbers and see what your Desktop Dyno says?
Still like the Magnum 282S cam also....guess they should be close in HP and TQ numbers......
Thanks

Brettmc

I've got the big block version of that unit. I really like it. I won't go into all the specifics since they won't act the same in our different engines but I think you will like it. It's actually kind of a small cam in my BB so it should be real lopey in your SB. With the right tuning, it should make a lot power across a wide rpm range.

Need I say anything on break-in procedures? Let me suggest 3 things: 1) Use GM EOS at break-in. 2) Use some solid lifters with the laser-hole in the face (I have the Crower Cool-Face units) and 3) follow those break-in instructions to a T.

Oh, by the way, I don't know if you've ever had a solid lifter cam before but they make some noise. If you're a true motorhead you will absolutely love the mechanical music these things put out. I know I do!!

poor light but good sound

Brett

gkull

Have you considered this Crane cam? I ran it in a 1953 dodge pickup street rod. For all I know it might even be still running today because i sold it about 12 years ago. It's got a wide 114 lobe center so it's not as radical as the numbers would lead you to believe. I had the 274 extreme H-flat cam and didn't like it in a 355 ci.

Part Number: 113841 Grind Number: F-278-2 (REPLACES CC-278-2)
Engine Identification:
Start Yr. End Yr. Make Cyl Description
1957 1987 CHEVROLET 8 FAIR IDLE, MODERATE PERFORMANCE USAGE, GOOD MID-RANGE HP, BRACKET RACING, 3400-3800 CRUISE RPM, 10.0 TO 11.5 COMPRESSION RATIO ADVISED. BASIC RPM 3000-6500
Engine Size Configuration
262-400 C.I. V

Valve Setting: Intake .022 Exhaust .022 HOT

Lift: Intake @Cam 320 @Valve 480 All Lifts are based
on zero lash and theoretical rocker arm ratios.
Exhaust @ Cam 3334 @Valve 500
Rocker Arm Ratio 1.50

Cam Timing: TAPPET @.018
Lift: Opens Closes ADV Duration
Intake 29.0 BTDC 69.0 ABDC 278 °
Exhaust 82.0 BBDC 26.0 ATDC 288 °

Spring Requirements: Triple Dual Outer Inner
Part Number 96877
Loads Closed 126 LBS @ 1.850 or 1 27/32
Open 304 LBS @ 1.400
Recommended RPM range with matching components
Minimum RPM 3000
Maximum RPM 6800
Valve Float 7400

Cam Timing: TAPPET @.050
Lift: Opens Closes Max Lift Duration
Intake 10.0 BTDC 48.0 ABDC 109 238 °
Exhaust 63.0 BBDC 5.0 ATDC 119 248 °

73jst4fun

Thanks Brett for the helpful hints on cam break in, I've got all bases covered, if I don't GordonM has and he'll remind me

I couldn't find a chart for HP and Tq on that cam but I'm hoping it will pull across the band....

Loved the sound of solids so I'm going with them....

Brutal64

I'm using that cam and love it, you better be paying attention above 2500 RPM because things happen in a hurry. I was pulling 310RWHP/330Ft-lbs RWTQ before I put this cam in and am probably at ~325/350 now.

TRW 10:1 Flat tops
AFR 195 Aluminum heads
Summit Stage II rods
Comp Cams XS274S solid lifter
236/242 dur .501/.510 lift
Crane 1.52 roller rockers
Mallory Comp 9000 dist
Edelbrock Victor Jr.
Speed Demon 750 MS
Dynomax headers
Flowmaster 40's 2.5" exhaust, H-pipe
4sp/3.55

L-82kid

I'll run your numbers when I get home from work today. Should be around 6:30-7pm.

73jst4fun

I really appreciate your info, I'm will be using some of your components, TRW pistons #464664 flat tops, AFR heads , 1.52 rockers, Flowmasters 50's wit H pipe, Air gap manifold, Demon carb 650, but will probubly switch to a Mighty Demon 750....glad to see your having good results, must put you in the high 12"s ....

73jst4fun

Thanks...

73jst4fun

Gkull, I'd have to change the convertor in my application for the 3,000 rpms stall needed...nice cam though....

Super Stock

Hey Brett , what is your comp. ratio ? What's the idle rpm and what does it pull to ? It sounds sweet .

gkull

I ran the DD2000 on both of them. Very simular power outputs. the 274 110 lobe center gives it 19 degrees of overlap at .050 VS 15 degrees for the Crane. The crane will have better mpg. The CC will have more of an idle lope do to overlap.

Both of them only ask for 2200+ stall converters.

73jst4fun

The Comp Cam calls for 2,000-6,400 rpms the Crane cam calls for 3,000-6,800 rpms, for launch with the THD I think the CC may be better, less heat build up especially in traffic. I agree about the lope...that Power Max is a good cam and been around for years, any charts for tq and hp available?

L-82kid

Dyno says:

XS274S

headers w/mufflers

440hp @ 6,000rpm
436 torque @ 4,500rpm

The torque is 375@ 2,000rpm then stays above 400'lbs up to ~5,800 rpm



headers w/ open exhaust
463hp @6,000rpm
452 torque @ 4,500rpm