Exhaust exhaust manifold leak

I think, if it were me, I'd go back to what we discussed a while back. See about picking up another set of heads and swapping them, particularly the 3 bar GT40 heads from an Explorer. Chances are pretty good that you can still pick up a set that are still good, install new springs and seals, and run from there. OR, remove your heads, take them in somewhere and have them gone through, which should involve new guides and seals. That's probably the cheaper route whereas the GT40 head route would most likely deliver a tad better performance overall. In either event, I'd look into having a set of heads that I felt better about the guides and seals.....
 
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Okay I agree. Wasn't there a specific year of the GT40's? I'm going to check with Wagamon's and see what they have.
I really appreciate your help.
Thanks,
Enzio
 
If its that loose its gonna start smoking out the exhaust,
new seals don't fix loose valves

time for rebuild
or shiney new Aluminum heads
 
I like the Edelbrock heads I have on my other 289, performer RPMs with the smaller valves for the stock pistons and matching rpm cam.
 
I think the Eddy heads are another step above the GT40s, so you would definitely be picking up more performance as well as something that would work well if you were to add more performance options in the future (i.e. cam, manifold, carb, etc.). The GT40s are pretty good and would benefit from all of that too, just not as well as the Eddy heads. BUT, the GT40s, if you can find them easily in your selected yard, will probably be the best bang for your buck. I'm gonna guess you can get them for <$300 a set whereas the Eddy head, or pretty much any aftermarket head for that matter, will probably run you around $1k/set. And, since you already have the springs and know how to set them, replacing the seals and springs on the GT40s would be an at-home job. The only thing you'd probably want to do is double check the guide clearances and make sure the valves aren't sloppy like your heads are, maybe lap the valves, throw your new components on them and go. The upside would be you'd be into them for roughly $500 vs the +/-$1000 for the Eddys. A con could be that you may still have to send them to a shop to have new guides installed. As for the Eddys, chances are pretty good that you could order them and basically just throw them on the car. Most everything should be good, but I'd double check everything anyway. You never know who threw the components together, but Edelbrock should have a reputation to uphold, so they should stand behind their product.

I guess what I'm trying to say, in my long winded way, is that either choice would be good as your engine sits now. The choice is yours as to how far you want to go with it all. :cheers:

Now, if you decide to go with aftermarket, there are a plethora of options; some more expensive, some less. One example off the top of my head would be Speedway Motor's Flo-Tek heads:


They were compared to other offerings and did fairly well as Hot Rod tested and published:


There are SO many options! Of course, it all depends on how far you wanna go and how much $$$ you wanna spend.... ;)
 
Good articles. Thanks.
I had a few adult beverages last night...and the wisdom gained from that has given me this plan. Subject to any or all change(s).
I'm packing to go hunting this afternoon. I'll be back when I'm back. I've worked my butt off on this car for the last two summers and being retired I've missed out on too much fishing and hunting. This will provide me time to contemplate this endeavor while enjoying myself. I need to cut some firewood for the winter also.
I'm trying to figure out how to pull the motor in my small garage. I think it's possible but I'm running out of time with winter coming and I have lots of plans all the way through the fall and winter.
When I get back from hunting, I may just put it back together and let it sit for the winter while I accumulate the necessary parts. And, after the snow melts, I'll start to take it apart. I'm not looking forward to pulling the transmission, bell housing, and clutch, I can tell you that much. Is it even possible to pull the motor and leave the tranny in place?
But, with the motor out I'll plan on installing a cam also. And, it'll allow me to replace the rear main seal. That will be the next thing to go bad.
Yesterday after I saw the bad valve guide on #5, I posted on the stangnet. after just looking at Eddy. I'm open to all aftermarket, trusted parts combinations. I've got a performer manifold #2121 and a #1405 carb, with the headers. I'd like to keep them as they fit under the hood and I'm only looking to make 300+ HP.
End result I want a reliable semi high performance fun car to drive next summer while I go visit friends and family around the country.
I'm not defeated; I'm just delayed.
I'm really grateful for the help and words of encouragement from the stangnet bros.
 
People pull motors out of cars all the time and leave the transmission in the car. I pulled the 302 out of my Bronco once to replace the rear main seal. I would imagine you will have to remove the hood, I've never worked on a II. Using a cherry picker you should be able to get the engine out. However, with the headers and everything in the way It might be easier just to pull it all out. I would think you could unbolt the headers, your running long tubes right, and then be able to get to the bolts you need to get to. And a friend or two. You'll definitely need extra hands. That's my $0.02.
 
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I've never tried pulling just the engine from my II, I've always pulled it all. But if you removed the transmission first, then the engine, it's a HELLUVALOT easier! I've either done it that way, which I prefer now that I've done it a couple times, or as an assembly. But I've never tried just the engine by itself. I'd think that the input shaft of the transmission would make is all but impossible to do if you were looking to leave the transmission in the car.
 
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That's what I was thinking. Getting it back in would be almost impossible if I could get it out. I love/hate the headers.
The tranny isn't that hard to do. Would you suggest pulling the motor-bell housing/clutch as one and then work the headers off as it comes off the motor mounts? Same as they go on?
 
Yep, that's basically what I'd do. So much easier to access the header bolts with it hanging compared to being in the car. Same with installing them. I'm pretty sure we have the same headers - the old Black Jacks that aren't made anymore. It's almost like they made them to be installed with the engine/transmission as a unit, since they weren't meant to be used with the 4 speed. It took a little massaging to make them work in my car with the 4 speed bell and clutch fork.
 
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You made me smile...I was remembering when I got the blackjacks, and was frequently on mustangii.net. Went through the massages with about 20 other guys with 4 speeds.
 
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iweAB2p.jpg
 
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so true. I've got dents all over them in just the right spots as I'm sure you do and you've seen the clutch fork with no dust cover and a nice notch in the fin of the bell.
 
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Back from hunting for a little while. Waiting for frost. Got the first load of firewood unloaded and stacked. I put the Cobra II back together this morning and got it running. I'm going to need to move things around in the garage in order to get the engine pulled in the spring so I'll need to keep it going through the winter in order to do so.
I pull the broken rocker (see post #29) off and replaced it. I'm pretty sure it was a casting flaw. Either way it doesn't have to last long.
 

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Replace those paper Mr. Gasket gaskets with the aluminum ones. They'll deform to fill the imperfections between the parts.

Locking header bolts also help. Standard header bolts are fine, but you'll want to check them at least every oil change. Locking bolts eliminate that extra maintenance.
Well I am waiting for parts and decided to revisit the leaking headers. I found the locking bolts you refer to. The are Proform header bolts. Summit and jegs sell them.
 
You can hacksaw the flanges in between the tubes the headers will seal up much better as individual tubes. You just have to be more careful handling them when they are unbolted from the car as they are less rigid than when attached together.
 
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The installed height of a valve spring is only really useful on a new valve spring, and is ultra important in the performance of an engine.
Installed height is calculated to be the height at which a particular NEW valve spring has its designed seat tension and also will not coil bind with its intended use cam at full lift.

All of this changes with a "used" spring.

A spring, once removed, which measures less than it's "free height" specified range when new, has lost tension and therefore cannot be used at the recommended installed height. This is where the shims come in for a stock non-high performance rebuild. On a stock engine with low lift there is plenty of extra space in between the coils, so using a shim underneath restores the correct spring pressure (at least for a while) and maintains clearance for coil bind.This is attained at a "less than" specified installed height. This works fine on stock engines (grocery getters) and stock usage (no high revs). To do this correctly you need a valve spring tension tool to see what height is required for the seat pressure needed for the application.

In a high performance engine this is a no-no because there is less coil bind clearance to do this, and more chance for bind. Any more than minor shimming means you either do not have the correct spring, or its worn beyond usage, or some other problem. New springs are the ticket if you have less free height range than listed for that spring. If you have a valve spring tension tool you can evaluate springs correctly, other wise it is simply a guess. All high performance springs even when new should be checked on a valve spring tension tool to ascertain whether they match their listed specs or not. I have seen many "brand new" sets with bad or incorrect springs in them, as well as new heads with mis-matched springs on them. I personally never trust any springs I don't measure anymore, and I have never wiped out a cam even in the era of flat tappet cam death.

For a country-boy back yard method you can use a decent quality bathroom scale and a c clamp and slide calipers, but this is something that is better done on proper equipment.
 
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Makes perfect sense to me. I'll refer to this when the time comes to rebuild the old motor. Thank you, I've been wondering about that question for quite a while.