Installing Exhaust Manifolds-1968 Sport Fury

[Vin_Fury]

So I bought a 1968 Sport Fury a few months ago and I have been doing some work to it and I decided to change out the headers the previous owner installed for the stock high-flow manifolds. The headers are out, but I cant seem to get the manifolds back in. The bolts don't want to torque. I decided to stick with the header bolts (the manifold's flange is the same thickness as the header's so the head wouldn't receive and more or less bolt) because I really didn't like the way the studs worked. Some of them torque fine while others -although there was no previous damage noticed when I removed the headers- turn until they're stripped. Plus, I think one of the holes in the head is now stripped but wont know for sure till I get a better look.
Anyway, is there something I'm doing wrong? Is there something I can change? I'd rather not remove the head and bring it someplace and I still feel that something just is not right! Any insight would be helpful. I must note also that I am not a mechanic, but just someone who is handy and reads/screws up as his source of learning. Thank!

 

[commando1]

Welcome.
Is this on the 318 or the 383/440?

 

[bluefury361]

I'm guessing it is not a 318 because of the mention of "hi flow" manifolds.
......... :sSig_greetingsthor:

The "B" & "RB" mopar engines were studded for exhaust manifold mounting. The studs screwed directly into the water jacket on the head. If a head stud hole is stripped you will likely end up with a coolant leak. Also, the HP manifolds required at least a couple of special nuts. (long with a threaded hole at one end and a hex head on the other).

No gaskets from the factory, but if you don't have the manifolds surfaced then you should use an aftermarket gasket to seal them.

A factory service manual will prove very helpful and is worth the cost.

 

[70bigblockdodge]

Bolts..... bad idea sounds like 12 coolant leaks.

 

[Vin_Fury]

Sorry, I forgot to mention I have a 383. And I noticed that the hardware kits are built for the few areas in the manifold that have cylinders leading to the flange. A thin wall socket and some patients does the trick with the bolts though. Is it a bad idea to use bolts with manifolds?

 

[70bigblockdodge]

Use lots of thread sealant.

 

[commando1]

And 1 will leak, regardless.
I have a special brew but I'm waiting on the patent before my attorney will let me say anything more about it.

 

[bluefury361]

Yes...... bad idea. You can purchase the correct style stud and bolt kits from places like R/T specialties. What did your manifolds come off of.....? C bodys used a different left side manifold then the B & E bodys. Right side is interchangeable.

http://www.rtspecialties.net/search.asp
Then type "exhaust manifold kit into the search box.

 

[Vin_Fury]

The studs should easily turn into the head, correct? I had trouble getting them in and it really worried me so I decided against it but I think they were shitty ones. I can try that set but I shouldn't have trouble getting them into the head in my opinion.
and the manifolds were original with the car.

 

[commando1]

You have to use a thread chaser in the heads before installing the studs.
Make sure the threads on the stud are clean using a wire wheel (fine).
They should go in by hand.
Using the double nut method coaxes them if necessary.
Make sure you thread them into the head right up to the shoulder on the stud.

 

[RemCharger]

agree with all^^^^^. And dont screw the fine thread side into the head!!!

 

[70bigblockdodge]

I bought mine at Napa, will not help with the long nuts, hehehe, those can be had later

 

[Yatzee]

It's easier to strip the thread in an aluminum or cast head than it is to strip the threads on the bolts because the bolts are a high grade that are hardened and don't stretch with heat. If you think you've stripped a thread in the head a chase will confirm that. As you turn it inward it has a tendency to wobble because the threads are less than 70%. You can buy an insert kit ( like heli-coil ) that gives you an odd sized drill and an insert that will leave the hole and thread same as original. In many quality aluminum heads, the manufacturer automatically installs these inserts in anticipation of the customer over-torquing as if they were working with cast heads. In such an instance, the torque values of OE service manuals can not be used. I have a 383 in my "boat" and drilling and installing inserts should not be a problem as there is plenty of clearance. You should be aware that to do this properly you'll require a right-angle drill and magnetize the drill bit by leaving it on a magnet over night then applying grease on the tip before using. Barring that, you can buy studs with one size thread on one end and a different size on the other so you could just drill and tap the bitched holes to one size larger.The studs in my heads are course thread in the head, fine threads for the nuts for the headers quaranteeing the nuts will always come off before the stud unthreads from the heads.

 

[rumpfox]

3/8 size studs not 5/16 that smallblocks are. i've never seen the threads strip out in bigblock heads. smallblocks yes .

 

[Vin_Fury]

I'm going to get myself a better set of studs and start over. Thanks for the help!
I'm also selling a set of Hooker Super Competition headers if anyone is interested

 

[70bigblockdodge]

I'm going to get myself a better set of studs and start over. Thanks for the help!
I'm also selling a set of Hooker Super Competition headers if anyone is interested

Got a picture and price?

 

[Vin_Fury]

Oh I didn't notice all the other responses. Thank you everyone for the help! I should have the new studs in a week or so so hopefully this will work! Here is a photo of the headers. They have surface rust even tho they were coated (I hear that's why they started rusting) they can be cleaned