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1972-74 302W with 2V heads

This came out of a CA car so it had internal air injection for smog regs. I am eliminating the left over piping. The picture shows what I'm eliminating. My question is can I use the bolts in the picture, which held the pipe to the heads, or should I use something else...and if so what are the suggestions?

Next question - the engine came with heads described but with a Edlebrock 289 Performer intake manifold and an Edlebrock 4V carb. Since the heads were designed for a 2V carb is there anything special I need to do when I rebuild/re-assemble. The engine ran very good as is but just wondering if any adjustments or changes are needed.

FYI - I'm not sure yet what's inside but either way I'm probably not going to do anything radical...if its standard I'll probably leave it standard (depending on condition of course). the same goes if it has been bored oversize. (Everything looks very clean, it wasn't smoking and the plugs looked like everything was functioning well)

759820
759822
 

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The heads probably don't have enough thread to use the factory air injection bolts. Thread the bolts into the head and mark how deep they go. Measure the depth and take a trip to your local hardware store and grab a couple bolts in the same thread size and 1/4" shorter than the thread depth. A little hi temp RTV on the threads and pop them in.
 

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289s and 302s did not have different heads depending upon whether it was a 2V or a 4V. Only the 289 HiPo and maybe the '68 J code 302 used a different head. So your heads don't know what carburetor is up top.
 

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I believe the smog tubes actually have a special thread.
 

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I believe the smog tubes actually have a special thread.
I think it's a pipe thread. A friend of mine always threads in pipe plugs to block them off and it works well.

The 351 Cleveland has 2V and 4V heads. 4V heads have ginormous ports and either open or closed combustion chambers. 2V has slightly smaller ports, but still huge compared to any other small block heads, and open combustion chambers. (Aussie Cleveland heads have the smaller ports and small, closed combustion chambers.)

The 1969 351W had 2V and 4V versions. The 4V had higher compression as well as a 4V carb and intake. I don't know if there was any other difference.

I'm not aware of any difference between 289/302 4V or 2V heads.
 

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Those banjo bolts (so-called because they pass through a banjo fitting) should be straight, not tapered. Banjo bolts are still commonly in use on disc brake calipers.

I don't recall anything special about the thread count.

The 351C 2V engine requires a special aftermarket 4V intake to match the 2V heads. There are several such available.
 

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In 68 the 2V and 4V heads are different on the 289/302 engines. The 2V heads are lower compression. The 4V heads are essentially the same as the 66/67 289 non HiPo heads.
 
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