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Well, I will be getting a few extra hundred bucks late this week or early next week, and have decided to throw a cam and some pistons in my 302. Should I waste my time doing this? I don't have any clue on the miles of the engine, but it's really strong, hauls ass for what it is (74 302 with 8.0.1 compression!). I would like to bump the compression up a ways, and throw in the beefiest cam I can :D I don't care if the thing idles at 2 grand lol. Any ideas on what I should throw in there? Current mods (Not much) are listed below.

Thanks

Chris
 

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Get a leakdown test. How many miles on the bottom? If it is good, I would put the money into smaller cc heads to bump the cr (and do alittle work on them) and the cam.
If the engine is tired, by all means tear it down, then bump the cr with the pistons if you like.
 

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Get a 351!

Your other post says this engine has a compression problem. Don't waste your time on a clapped out 302, your car originally came with one of Ford's best engines, a 351 Windsor. You should be able to score one at a wrecking yard, complete guaranteed and running for under $500.00 that will outperform a wimpy 302 in your heavy Cougar any day. Get that installed and consider mods after getting the right motor in your car.

Royce Peterson
 

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I could take offense at calling a 302 "wimpy", but I'll let it go since the guy saying it has 3 big block Cougars!!

My car is a 68', weighs 3200 lbs with me in it... do the 69/70's weigh that much more?? My best pass so far, with a wimpy 302, is 13.8...

There are so many variables to consider with his question... they boil down to how worn out is the 302, and how much pain and suffering to swap into a tired, junkyard 351W. Header locations are higher due to increased block height is one that just comes to the top of my head... Distributor is different... Hmm, what else...

People like Crane or Comp Cams can recommend a cam... how out of control do you want to be? is the question... I'd say you probably should stay in the hydraulic lifter range to avoid having to make frequent valve lash adjustments and having a noisy valve train... Plus a LOT bigger cam will get you into valve springs, full roller rockers, thread-in studs... etc... Lots of $$ in your heads.

You can make up a lot of compression due to your combustion chamber size... I think the 74's were big due to the emissions baloney... You'll know a lot more after you pull the heads, you'll see what pistons you have, see your combustion chambers, see you big giant EGR bumps in the exhaust ports, and you will be able to tell if you have a big ridge at the top of your cylinder bores from excessive wear. Take your time, drive a beater while the Cougar is torn down, and have fun with it...

Or just be like Royce, Big Power=Big Block!
 

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302's

I am not intending to say all 302's are wimpy but a stock 74 302 is among the wimpiest. Cubic inches never hurt a thing. When I talk about junkyard motors for $500.00 I mean with all accessories such as carb, distributor, etc. There are so many 351W's in a good sized yard that one should be a good usable one that won't foam the radiator.

You could of course fix the 302 that is installed, a good start would be a better set of heads. Early 289 heads with a small combustion chamber (45 - 60 CC's depending upon year) will give you more compression cheaper and easier than a piston swap. Tri - Y headers are also cheap and give good bang for the buck.

Ultimately, the question is how fast does it need to be and how much are you willing to spend? At some point the 351W will be more cost effective and more powerful at any RPM.

Royce Peterson
 

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302 mods

Definitely do a leakdown test, and consider dropping the pan to see what kind of shape this motor is in. Adding more compression to a 302 of unknown condition could result in a 5 liter hand grenade. If you want more power than your 302, save the money, and keep saving until you can afford to build a fresh, stout 351 windsor. The 302 to 351 swap is simple. Don't get me wrong, the 302 is a good motor, but if you are going to build one, go for the extra cubes!! If you are intent on doing the 302 invest in the bottom end and heads first, without that, the rest of the motor will never live up to it's potential.
Paul G.
69 XR7 Convertible
(patiently awaiting the 428 swap)
 

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IMHO I wouldn't even attempt to "throw in a set of pistons" into a used engine like that. The very least you need to do, and that's on a brand new engine, would be to hone the cylinders. When you hone, all that metal dust gets washed down into the lower end. On a high miles engine you will have bores that are worn and have a ridge at the top. You cannot just hone the cylinder and put in new pistons, you must have the block bored out. To do all that the engine must be torn down and ultimately rebuilt.
 

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This is all good, and all of it is right, too.

Royce, I'm going through this same exercise in my mind with my 302... my motor makes just under 400 hp, but with a wild cam and rough idle... not a real "fun" streetable setup, but hauls the mail. Lots of time, effort, and money in a rig like this. I'll eventually tune my motor til' I run as fast as it will go... hopefully in the high 12's, but then I'll inevitably want to go faster... I presently have a set of DOOE-C 351W heads, fully ported and polished to the big FelPro gaskets... So I'm thinking I'll probably build up a 351W short block over the next couple years for when I max out or blow up the 302. It's just too bad that some key parts don't interchange... cam, distributor, intake?, headers...

Is it possible to run the 302 firing order in a 351W by running the 302 cam and distributor?? I guess I never thought about that...

That way a lot of the "peripherals" would be reusable, particularly in this case with all of the high tech, high dollar Mallory ignition components Chris is running.

Ron.
 

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Ron, you can use the 302 cam with the 302 fireing order, but no way can you use the dist as the oil pump shaft is bigger on the 351. mm
 

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Oct. 2002, Mustng & Fords

CONSIDER THE CAM
Camshaft selection is also important and, as a rule, the torque curve moves up in the rpm band as the cam becomes more radical. That's why it's important not to choose too big a cam for your street-driven car, as much of the low-rpm torque is lost to a power curve that can be too high for good street performance and flexibility. Cam selection is a trade-off,and you'll have to compromise between good initial torque available at relatively low rpm and big horsepower numbers up top. Camshafts like the ones furnished stock by the manufacturer tend to have great low-end torque for smooth drivabillty, yet they nose over early on the dyno test. The show is allover by
4,000 rpm. A bigger cam sacrifices some of the low-rpm grunt for top-end power, where at 4,000 rpm the fun is in full swing. This tradeoff is your call, and your cam selection and installation will be dictated by how you plan to use your car.
When building your next Ford engine, you may wish to degree the cam for optimum performance. II sure is easier on the engine stand than when the engine is in the car.
 
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