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Hi Po exhaust manifolds

Just thinking right now as to what I am going to put on the '66. Tired of the current headers dragging over every little bump there is. HiPo's or shorties if I can get a fit.....

What would you want for them....of course with an unknown shipping amount.
 
Well Pete, if you are talking to me, $50.

I had the dragging problem once, but when I got a set of Headers By Doug (long tube tri-Ys) The problem went away. I think your 66 may sit just a bit lower than my two cars, not sure. I need to get my car down off the lift and measure for you.

Mel
 
The big deal on mine is the headers sit a ways off the floor pans, causing major clearance problems.... Will let you know on the decision......
 
I am also looking at several other ideas. The big problem I run into is that very few manufacturers will say their units will fit a '66 289 with '69 351 heads. Been doing this search for over a month now....just getting to the end soon.
 
I forgot you are running the 69 heads. I think that is more the problem, but not worth changing them out. IIRC the angle on the ports is just a bit different. This causes the headers to tilt and hang just a bit lower.

This was corrected IIRC on the 351 by having a slightly taller block.

I could be all wet, I am digging super deep since I wanted to install a 351 in a car I had in the 80s, that is when I did the research and decided I didn't want to. I ended up using 302 heads instead with higher compression pistons.

The 351 gives you bigger valves where the 302 does not.

Anyway, I think if you want the car to breathe right you should use shorties, or take it to a muffler shop. It is important to take it to a guy who builds vintage cars himself. I took my 65 to the local guy here who builds Mopars. Even has a pic of his car on his card. He is an A$$ but does know his stuff with exhaust. He suggested the headers by doug for my car.

I built the 67 in CA and used hooker tri-Ys I got from one of the Mustang parts houses, they were cheap and I was running out of cash.

Just a few thoughts. Oh, anyone want to make sure my memory is correct with regards to the 351 heads on a 289???

Mel
 
"AzPete" said:
I am also looking at several other ideas. The big problem I run into is that very few manufacturers will say their units will fit a '66 289 with '69 351 heads. Been doing this search for over a month now....just getting to the end soon.
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Why do they say this Pete? The 351W heads are identical to the 289 heads as far as bolting up manifolds/headers. It wouldn't surprise me if John shaved them significantly to boost compression, but we're only talking thousandths there. You wouldn't see that in ground clearance. Many headers give you limited ground clearance, and it sounds like these are no exception.
 
"monkeystash" said:
Why do they say this Pete? The 351W heads are identical to the 289 heads as far as bolting up manifolds/headers. It wouldn't surprise me if John shaved them significantly to boost compression, but we're only talking thousandths there. You wouldn't see that in ground clearance. Many headers give you limited ground clearance, and it sounds like these are no exception.
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Aren't the 351w heads larger and the exhaust ports at a slightly different angle?

If John shaved them then that would have the result of lowering the header tube. Granted not my much since we are talking about thousands. Still .250 over a distance can translate in more and when you can't make yourself slow down over speed bumps like Pete (hehehe) you are bound to drag.

I think the ride height would have a bunch to do with it and I know John rebuilt the front end of that car with some sort of a drop. It does ride pretty low.

Just curious about the 351w heads since I haven't done any research on it in a very long time. I just want to make sure I am thinking of the right combo. I may be mixing it up with something. I know there is a difference in height from a fully assembled 289 and 351w stock.

Mel
 
"guruatbol" said:
Aren't the 351w heads larger and the exhaust ports at a slightly different angle?

If John shaved them then that would have the result of lowering the header tube. Granted not my much since we are talking about thousands. Still .250 over a distance can translate in more and when you can't make yourself slow down over speed bumps like Pete (hehehe) you are bound to drag.
Click to expand...

No, they are the same.

Heads might be shaved .010-.050, not enough to affect ground clearance.
 
The biggest problem is that the "experts" just will not commit to the port shape and header fit....which is odd. I asked if they knew the exhaust port shape of the '69 351 heads. Yes....1.24 x .96. Good. Now, the port size on the 289 88400 headers......I forgot the numbers but same shape and larger than the heads. Well then, the headers for the 289 should fit the 351 heads in the '66. Aahhhh, welll, IIIII'mmmm nnnooott suuureee.... Llllettt mmmmeee check with the techs...... Five mins. later, I get a reply from a tech that since they do not have that setup listed, they cannot say they fit, so they do not recommend them. Then I asked why Summit listed the port shape as oval and they had no answer for that, even looking at the Summit site for them.

Anyway, I have a lead on a set of Sandersons from another Fixer so I may try them.

Here is the small clearance problem.....about 3.5 inches.....
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securedownload11.jpg
 
Florida is flat. What do you have to worry about.... Maybe drink less beer and walk a little more. :nk Problem solved. :good
 
"lethal289" said:
Florida is flat. What do you have to worry about.... Maybe drink less beer and walk a little more. :nk Problem solved. :good
Click to expand...

It's the damn armadillos and tourists that lie in the road and create clearance problems.
 
Must be the out of towners that get in the way.....I am out of Wattles so no beer......gotta do the CC Sherry Cask stuff now.....and also..... :bird
 
I have an AOD so I do not think they will clear. Got deal going on a set of Sandersons Shorties on the way to try.
 
Pete, if the heads are identical to the 289 heads as far as the ports are concerned, why not just pick up a cheap set of painted hookers like I have on the 67 and get R done?

I think you should tell the people you are buying from less info. Like you have a 289 and get them. As stated above, the ports are identical, so should be no problem.

I think shorties are OK, but I prefer long tube and unless you front end is dumped into the weeds you shouldn't have clearance issues. I don't on either car. My 65 had the front suspension redone by the PO and I have no idea what he did, so I have no idea what drop is on it, but there is some.

Mel
 
AOD is another issue....it is wider than a C4 so several long tubes will hit it.

I agree on telling less.......which is what I learned after some research. Thing is, several ask what heads as some after market heads require a different setup. This I also learned half way thru this problem.
 
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