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Merry Christmas everyone!

I have a 68 Georgia cougar that was bequeathed to my wife and I after her father passed a few months ago. Its a 1968 1 owner title with 42,000 miles and factory air conditioning. The car is in good shape but has sat for at least 15 years, the last 5 in a garage in Illinois. Although I got it running 2 months ago enough to move around in the driveway, basically everything needs to be gone through to make it reliable. In that thought, we want to make it a nice cruiser but with more power. I removed the original 302 and C4 3 weeks ago to do a power disc brake upgrade and overhaul the engine. Her fathers shop also contains a complete 1972 351 windsor 2 valve engine so now I wonder which is the best engine to rebuild and put back in the cougar?

I would like about 320 horsepower or so, any thoughts???
 

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Either engine will be overhauled. I had planned on edelbrock performer rpm heads, dual plane intake, 600 cfm carb, comp cams XE256 cam, and just about stock bottom end. Accessories are the worry I guess. The 351 has no brackets or accessories like AC, power steering etc. The original 302 is complete. I live in GA and the car is in IL. I get up there for 2 days every month. Everything is in the initial teardown stages.
 

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If you have limited time, make it easy on yourself and do the 302. All the parts are there and you won't have to waste time chasing down brackets and doodads and what not.
320 is easy for either one of those engines.
 

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tOM HERE ktlrestorations.com ----If you use the 351 needs pullys /brackets/change radiator or call me 4346857353 8am/9pm Danlle Va
 

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Don't forget the rear end gearing while you are planning your build...Big cam, stock gear= pooooor performance. Right cam and right gear, a need for new tires!-)))
 

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one more consideration in the use of a 351. Motor will sit higher and can cause hood clearance probs depending on intake. I use a performer plus and had to use a drop base air filter with a KN breather top lid. Header fitment is a prob too. But ..... the only substitute for cubic inches is cubic bucks. I went 408 stroker too.
 

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I'm not sure about the AC but I think you could make most of the brackets transfer to the W if I remember right? Take a close look and see if that's the case. You may only need longer belts..? If that's the case then I say rebuild the W if you plan to get new heads anyway - cuz you definitely don't want those 72 iron heads....and that's gonna easily give you the pony power you want.
 

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I'm not sure about the AC but I think you could make most of the brackets transfer to the W if I remember right? Take a close look and see if that's the case. You may only need longer belts..? If that's the case then I say rebuild the W if you plan to get new heads anyway - cuz you definitely don't want those 72 iron heads....and that's gonna easily give you the pony power you want.
I had to get adapters for putting 302 brackets on the 351. Jeffs Bronco Graveyard ( I think that was the name) had the conversion brackets at reasonable cost.
 

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To use the 351W you can use all the accessories (AC, alternator, P.S., motor mounts, pulleys) from the old motor on the 351W by simply using the 302 front cover, balancer and the bronco adapters mentioned previously. I used the small tube Hooker headers without a hitch, don't get carried away with the intake, I used the Edelbrock Performer RPM intake and a HiPo breather.
 

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Discussion Starter #11
To use the 351W you can use all the accessories (AC, alternator, P.S., motor mounts, pulleys) from the old motor on the 351W by simply using the 302 front cover, balancer and the bronco adapters mentioned previously. I used the small tube Hooker headers without a hitch, don't get carried away with the intake, I used the Edelbrock Performer RPM intake and a HiPo breather.[/QUOTE

Thanks Everyone.

For those who have accomplished this swap, how many went with aftermarket cylinder heads? Will the 68 302 balancer fit the 72 351? Any hood clearance issues with the stock AC compressor?
 

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I believe the 302 can be stroked to a 331. I think it can be stroked higher, but the process gets more complicated and adds risk of additional wear and shorter life of the build. I'm not sure how much horsepower is gained by stroking the 302 to 331. Others here will have to answer that or there are lots of articles on it here on the internet, just do a search for 331 stroker.
 

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For those who have accomplished this swap, how many went with aftermarket cylinder heads?
I used the Edelbrock #6025 heads.
Will the 68 302 balancer fit the 72 351?
Yes, both engines balanced the same. If you don't change to the 68 front cover you'll need to re-mark the balancer or use a timing tape, the 72 engine times from the right side. I would use a 68 front cover and timing pointer along with the 68 balancer and water pump.
Any hood clearance issues with the stock AC compressor?
No, but you will need to use the 351W AC brackets or modify the 302 brackets.
 

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Ok I've been down this road twice now.. If the 302 is running great and you don't need to do any work thats cool.. However, if you are going to start putting money in it (And as soon as you say aftermarket heads you are) you need to ask yourself whats the better return on investment? A 302 cubic inch or a 351 cubic inch? If you have both engines to start with why go with the smaller one? I have pulled engines a few times so I'll admit it's not my first rodeo but I did a re and re (302/351)in a matter of ~3 hours. The exact time escales me at the moment but it was between lunch and diner and I had a couple hours of spare time in between.

So it boils down to what is the right motor for what YOU want :) If it was me I'd take the 351 in a heartbeat. 20% more cubes out of the gate, one of the biggest aftermarket engine lines out there and if you ever get the hankering for real power what would you rather do? Drop $4k stroking a 302 to 331 or drop $4k stroking a 351 to 408? :)

Either engine with some mods is going to be fun to drive and as somone mentioned watch your rear gearing to make sure it's where you need it to be. $500 on a set of 3.50s is a HUGE improvement over the stock 2.80s or 2.79s most of our cars came with. Do what you want to do. It's your car.

Clearance wise, if I recall a lowrise standard aluminum intake like the performer will fit under the hood on a 351. (please someone back me up on this as I've had my hood off for 2 years now.) but my airgap RPM definitely will not fit. Aftermarket rads pose clearance issues as well on the front end but I massaged the big block rad brackets to make it work.

Eitehr way, good luck
 

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I go to the local U-Pull It yards seem thay have plenty of the 351's and I will snatch brkts from them .
 
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