Here is the cam specs from the cam installed in my 73 454. It is a summit cam. I bought the car this way. The engine was rebuilt all stock with exception of the cam. That means it probably has 8.5:1 compression. Is this to much cam for the stock compression ratio. It has a wide LSA of 114 I was'nt sure how much that affected the agressiveness of the cam. Help and opinions would be awesome..

Cam Style:Hydraulic flat tappet
Basic Operating RPM Range:3,000-6,500
Duration at 050 inch Lift:238 int./248 exh.
Advertised Duration:296 int./306 exh.
Lift with Factory Rocker Arm Ratio:0.540 int./0.540 exh.
Lobe Separation (degrees):114

Way too much cam, imho..

Imho, at 7.9 to 8.+ to 1 CR, I would run a CC 268HE or 270 Magnum , a Crane 272/272 Energizer or an Isky 270 Mega and be done w/ it..

Or, call Harold up and run the one he say's to USE!!

Guy's, I know a 280 cam can be used here, but why????

pdq67

Other considerations are, converter stall speed, rear gears, uses of car.

No, imho, that other stuff is just fluff, b/c a certain SCR engine really need's a certain DCR-producing cam in it regardless..

The other stuff just crutche's it, imho..

pdq67

Another question. How much compression would it take to make this cam work? Could it be done with a head swap?

I do not want to tear into the bottom end so piston change is out of the question.

Would I be better off changing both heads and cam?

I would like the optimum setup that will have the most power possible while running on 91 pump gas. Thats all that I can get where I live.

If I was to leave the stock heads and pistons and simply change the cam what kind of power could I make?

Thanks guys..

Sorry guys forgot to mention the car is a 4 speed. Not sure on the gear ratio yet.

I was thinking I might like to run the Comp Cams XE268 or XE274

We put this same cam into a stock,flat top 8 to 1 454 exactly what you have.
Motor is in a 69 SS396 car...it runs low,low 13's with 3.07 gears and auto w/mild convertor.
This is with no tuning.
Here is a picture of it leaving the line:
http://www.chevelles.com/showroom/data/500/medium/bowman69SS.jpg
http://www.chevelles.com/showroom/data/500/medium/69ss6.jpg

Don't listen to anyone that tells you it won't work..thats because they haven't tried it and over think it. This cam idles fairly smooth for what it is and has no lack of low end power. It pulls like a damn freight train.

IF it is a TRUE 296/306 cam, then I figure that it really need's at least 11.5 to 1 to run like it was meant to be ran way back when we had good high octane gasoline!

Sure, it will run, but why run one that's too big to begin w/ b/c of all the midrange you will leave on the table??

As always, jmho..

And my 8 to 1 454 P/U engine, (I think had), CC's 280 Mgnum in it and it did run, but was weak down low!!

pdq67

Even with this big cam,it has enough torque to cut a 1.82 60 ft. with 3.07 gears.
Again,this cam will work just fine. Only other bolt on where an HEI,RPM Air Gap,3310 Holley and small tube headers.

Chris,

I'm not doubting you at all, BUT why run too big a cam??

If it is a new cam, ebay it!

If it is used, mothball or can it b/c a cam isn't all that high priced!!

I wouldn't run bigger than the old Crane 284 Energizer spec'd at;

284/228, 112/107, .544" hy-cam... (And I'm pretty sure Summit has it in a cheap house-cam. Please check)..

And to me, at about 8 to 1, even it is too big as was the CC 280 Mthat was in my P/U motor when I bought it off the guy that had it before me!!

pdq67

Leave it, a 454HO with a 274XE (240/246)Comp put put 538tq/538hp and Eddy RPM and Holley carb. If anything advance it 4* for more dynamic compression.

Big cam, tight converter, limited tires all go hand in hand. Question becomes, is it the best combo? No, not really, but others have used worse combos and still got decent results. They used to make (still may do so) "cheater" cams for Stock class racing. The lift had to be stock, but the duration could be anything up to the factory advertised duration numbers. Needless to say, the tried and true GM big block hyd that was 214/218, .460/.480 ended up somewhere around that 296-304 number with .050 timing in the 240 range. '71 454-LS5 motor (8.5/1) ran this cam in BS-A. So yes it can be done, maybe not the best, but doable non-the-less.

if it works, don't screw with it.

Leave it, a 454HO with a 274XE (240/246)Comp put put 538tq/538hp and Eddy RPM and Holley carb. If anything advance it 4* for more dynamic compression.

Yeah that is a good artical. It was 538tq/508hp though

http://www.corvettefever.com/techarticles/153_0312_454_cam_profile_testing/index.html

Oops, meant the 284XE, that is why I recommend advancing it 4*, it will give you ~.25 dynamic compression improvement. I really think it will be fine. I ran a 246* @.050 in a 400SB w/9:1 in high school that flat hauled. I would break 30" street slicks loose with a 3.31(if that good) gear. All those cams in the article were within 200 rpm of peak tq, just kept adding hp. With a good dual plane, carb and decent exhaust you'll be fine.