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Discussion Starter #1
How much painful machining to install Boss 302 heads/intake onto an original 68 F code 2Bbl 302. My "stock" 302 is presently equipped with BIG cam, low rise single plane manifold, and an original Boss 302 780 cfm Holley carb. My cylinder heads are from a 65 Mustang, 289, that have been retrofitted with 2.02" intake valves and 1.60" exhaust valves, but seem to fall flat in the last couple hundred feet of a run. I'd interested in any info on the differences between the Boss 302 block and the stock 302 blocks.

Ron.
 

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I'm reaching back into a foggy memory but I think the Boss 302 heads will bolt right on. They already had the water rerouted for the 302 block when compared the the original Cleavland style casting. The boss 302 block was a heavy duty part compared to the regular block, 4 bolt mains, stronger rods and bolts and forged pistons that cracked alot.

Let me ask a couple questions now. Do you already own a set of boss 302 heads and intake? Why do you really want a fake Boss 302? Is it just for the nostailga, or do you really think they are the best thing running.

With the multitude of aftermarket sb Ford heads on the market now the cost of getting a set of original Boss 302 heads just dont make sense unless its just something you think you have to have. From a stictly perfomance standpoint there are better heads availible now even more so for a street machine.

A friend of mine had a 70 Boss 302 back in 75 and I have rode in and drivin the car. Its legand is well deserved but it wasnt the most pleasureable every day around town driver. All that high revving HP came at the expense of very little low or mid range torque. You will be hard on clutches driving around town everyday.

If your sure you want the fake Boss but are not a drag racer, I would suggest using a set of 2V Cleavland heads instead. All you have to do is block off the water holes in the face of the deck and drill a hole in the intake side of the head. You will need a special intake for the swap though. B A Ford performance used to make a couple intakes for the swap. The 2v heads make much more power than the stock 302 heads and have smaller ports and valves than the 4v's which vastly improve around town drivealbility and it will still look like a Boss 302. mm
 

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Discussion Starter #3
The answer is "yes", I do have the heads and intake. I'm not hung up on nostalgia, I just want to make power. My car has the C4 auto transmission with a 10" converter, so clutches aren't an issue. I'm not a purist racer either, I'll have the thing street legal but only as a fun car, not at all a regular driver. The cam I have in it now is a solid lifter/ rough idle unit, so you see I'm not particular about creature comforts. I would be dissapointed in goofing up the present power band of 1500-6000 rpm. The lower end is presently balanced, etc... to produce a safe, sustained 8000, but have not intentions of going beyond 6800, intentionally. I'm concerned about finding headers to fit the boss heads, too.
Ron.
 

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I just got to thinking about the Boss 302 heads and realized I forgot to mention that you have to remember that the Boss 302 heads have canted valves. The valve reliefs in your 302 pistons wont line up with the valves. You more than likely will have valves hitting pistons unless you get a set of pistons with Cleavland style valve reliefs. I say they will goof up your power band if you expect anything below 2000 rpm with them. You missed the point when you said you would be alright since you have a C4. Why do you think a Boss 302 was never offered with a auto? Ford knew that those big ports and valves wouldnt work very well without reworking a automatic. I guess it depends how far you want to go, but I get the feeling you didnt want to get into replacing perfectly good pistons. mm
 

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The pistons may not be the only problem with those big valves. As I recall, my 351C had notches at the top of the cylinders to let the valve by....

According to Ford, the only part in common between the SB and Boss heads is the bolt pattern. They recommend
installing 351W heads instead. With appropriate pistons to offset the larger chamber sizes, etc.
Either one is a chore.

As MM stated earlier, you're better off to get a set of aftermarket SB heads.

You can eBay or swap meet your Boss parts to help offset the cost.

If you are really set on bolting on y\those Boss parts, well, anything is doable - how much $$ have you got?
 

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Boss 302 headers

Headers won't be a problem. The '68 cougar is basically the same chassis as the '69-70 Boss 302 Mustang. Hooker 6209 will fit, but it is a bit pricey at ~$500. Maybe try a 1970 351C-4V Mustang/Cougar header from a bargin brand to see if it will fit.
 

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Discussion Starter #7
I appreciate all of this valuable advice. I think I'm officially talked out of it by virtue of the lost lower end torque. My pistons have already been machined to accommodate the Che%#* 2.02" and 1.60" valves that are in my heads, due to the .560 lift and 294 duration cam. Had some interference problems there already. Custom machining is something my present cylinder heads are already used to. The transmission has already been reworked, too, so I'm not concerned with overstressing that unit either. Thanks again for the advice, this sort of discussion has helped more than just me I'm sure. No sense re-learning all of the things others have already went through the pain with.

Ron.
 
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