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CAM question and need your WISDOM

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Old Aug 10, 2014 | 01:07 PM
  #1  
ajmanning84's Avatar
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From: Ardmore , Oklahoma
Lightbulb CAM question and need your WISDOM

I have a 1971 Cutlass S with a almost stock 350 with t400 trans and 2.68 gears (or close to that gearing but will be upgrading to 3.73)

I am needing to know whats the BIGGEST cam I can put in my car.

I have :

- #8 heads with upgraded springs and a valve job (I was told these heads are low compression)
- Hooker super comp headers
- Edlebrock 4 barrel carb
- Performer rpm intake
- Mallory HEI distributor with accel coil
- Double roller timing chain
- Msd spark plug wires
- Stock pedestal rockers and flat tap lifters

Anything else you need to know feel free to ask and if I know or can find out I will.

Thankyou and fill me with your WISDOM lol.
Old Aug 10, 2014 | 02:01 PM
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You really need to know what pistons are in there in order to hazard a guess at the compression ratio.

The '71 engine originally had very large dish pistons (~25cc) and the heads were ~68cc. Now you have #8 heads with 80+cc chambers, so if that engine has the original pistons your compression ratio may be as low as 7.0:1. If that's the case, don't go any larger than a factory cam.
Old Aug 10, 2014 | 02:08 PM
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Why 3.73 on a stock engine? probably better off with 3.42 for street use. My car spins 3000rpm at 65-70mph with 3.42's., just to give you am idea. I wouldn't waste my money on the cam if the engine is stock. JMO
Old Aug 10, 2014 | 02:09 PM
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ajmanning84's Avatar
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Ive been looking at

Bracket Master Hydraulic Flat Tappet Cam & Lifter Kit - Oldsmobile V8 290/300



Please tell me if this is a good idea or a bad idea and I can post a picture of my pistons if that helps any. Also does this mean you could tell me my compression ratio. Im very new to all the specs on stuff.
Old Aug 10, 2014 | 02:13 PM
  #5  
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not sure how well you can see the top of my pistions but this is the best pic i have of them. I have a small dish in the middle of them.
Attached Images
Old Aug 10, 2014 | 02:16 PM
  #6  
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Bad idea, with that compression this would make the car slower.
Old Aug 10, 2014 | 02:23 PM
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Originally Posted by 70cutty
Bad idea, with that compression this would make the car slower.
I want to give my car more of a loap, and and more torque. The gears I have in the rear right now at 70mph im at just 2500 - 2600 rpms.

I want to accelerate faster
Old Aug 10, 2014 | 05:27 PM
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I would go with 3.42s forget about the cam until is time for rebuild. That cam will do the opposite, too much duration for your engine.
Old Aug 10, 2014 | 05:45 PM
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I can't tell from that picture what dish size those pistons might have.

Originally Posted by ajmanning84
I want to give my car more of a loap, and and more torque.
A larger cam will definitely give the lope, but if you don't have sufficient compression you will end up with LESS torque and you will accelerate SLOWER. It is ridiculously easy to overcam a low compression engine and ruin its performance.

Swapping rear gears will give better acceleration and make it feel as if your engine has more power. I agree that you should do this first.
Old Aug 10, 2014 | 06:26 PM
  #10  
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Should I change my heads an go with something that has higher compression so I can get a cam and not loose torque.

Im wanting to twin turbocharge at a later date.

If I change my heads what should I go with?
Old Jun 23, 2024 | 04:34 PM
  #11  
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Sorry to jump in on this, are stock 1971 #7 HEADS Better ? thanks
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