third coast

I have seen great advice from Basslicks in the past but I must reiterate my recommendation for staying away from a wire wheel. Especially the typical steel (vs. brass) wire wheel, which is harder than the softer cast iron head. And it definitely can easily gash up an aluminum intake manifold. The wire wheel also will shed little metal wire pieces that can get where they can cause additional problems. You don't want a piece of hard steel getting between a piston ring and cylinder wall. For someone with lots of experience, possessing the right wheel and a finesse for this procedure, maybe. There is a rubber/ceramic rotary disk made by 3M (Roloc bristle disc, white) that some professionals use on aluminum heads but even then there are those that will not use it due risk to ceramic particle debris contamination. It's too risky for the average person to use a random wire wheel and end up causing regrettable damage. Don’t take the chance.

Transpoquick

Something like this?

Wire wheel shrapnel is a fear of mine to.

3m gasket removal disk on a 90 degree 1/4" die grinder and a razor blade is a good solution.

Joecam18

Well team I think Ive done it. Got the header and manifold on with all the bolts that I could reach torqued appropriately. I fired it up with no pre cats, header only, and it went up to 2K RPMs and then settled down to around 1K. Ill keep yall posted about the rest of the install!

third coast

GREAT! Good to hear.

third coast

Manifold Bolt Washers

Ever wonder about those odd washers used on the manifold bolts? They are not flat but somewhat cup shaped. These unique washers are used under bolt heads that secure the cast iron exhaust manifold and aluminum intake manifold to the cylinder head on the Chrysler 4.0 engine, at least on later models. They will be found bridging between both the intake and exhaust manifolds in some cases. They are technically called conical spring washers or Belleville washers.

They were most likely selected for this application primarily due to the issue of the different coefficient of expansion of aluminum compared to cast iron. The intake manifold stays relatively cool from intake air while the exhaust manifold sees high temperature exhaust gas. The manifolds and the retaining bolts see a large swing in temperature from startup in subzero ambient temperatures to exhaust manifold temperatures that likely exceed 500 deg F while running under high speed and load. The challenge is to maintain a good seal across a wide temperature swing as the different materials expand at different rates. If some “give” or room for thermal expansion is not provided the bolts can also be overstressed to the point of early failure. If load supplied by the bolts is lost gasket failure and intake and exhaust leaks will result. The cone shape of the washer provides a spring effect that helps tolerate the different temperature between intake and exhaust manifold and to deal with the challenge of thermal expansion of the different metals. This type of washer provides uniform loading where it bridges between intake and exhaust manifolds.

What does this mean to you?

1) Don’t misplace or discard the washers! They perform a critical function. They are not readily available from Chrysler or other typical sources.

2) The preload on the washer as provided by specified bolt torque is important in maintaining good sealing of the intake and exhaust manifold to the head and long life of this system.

3) When reassembling manifolds the washers should have the outer diameter setting on the manifold surfaces and not overhanging in order to properly distribute and maintain the clamping load. The high or top part of the cone goes against the bolt head.

Best of success on your manifold related projects.

5-Speed

Please tell me you double checked intake flange thickness to exhaust flange thickness while you had it apart....

Joecam18

The header is a bit thicker than the manifold but it started up fine and al the washers are contacting both the manifold and the header

jessenator

If I get an APN-style header, get the pinch de-pinched on the front pipe…

1. Do I need a high flow muffler (e.g. Flowmaster 50)
and/or
2. Do I need an aftermarket cat?


…to make the new header and pinch removal worth it?


Also, I hope this doesn't come across as loaded—it's not meant to be.

5-Speed

This picture shows that it did not clamp very good on the intake ports as there is no indent around the port. You can see the marks from the exhaust ports but the intake portion still looks smooth. Yes I know this was prior to cleaning the surface and re torquing but it shouldnt matter. If the exhaust left indents, the intake should have too. Even a slight difference in thickness wont allow enough of a "bite" on the intake ports causing a leak. Say you have 25 lbs smashing the header ports, it may only be 5 lbs on the intake which is not enough. I know how not fun it is to change the header on the 00-01 so I would really hate to see you do it all again.

Would you say the header was a 1/16" thicker? 1/8" thicker? Even more?

SatiricalHen

I'm not sure to be honest, but I believe most of the rest of the exhaust is more free flowing than the pinch, but when I get around to for fun mods on my Comanche I plan to do a bored throttle body, 99+ intake, 96ish head, new style header, non crushed downpipe, flowmaster 44 (probably, haven't 100% decided on a muffler yet) and out the back. Open everything you can to get it breathing better. Also, if you're opening up the exhaust and intake. I would suggest upgrade injectors.

Joecam18

5-Speed

Is that a small gap on the intake port or an optical illusion? Like you said, the flanges do look pretty close to the same thickness.

Basslicks

To clarify, my recommendation was NOT for use on the aluminum intake manifold, but rather ONLY for the cast iron head... and even though the bristles are made of steel, they're not hard enough to cause any damage to the cast iron of the head. Also, I would think it goes without saying to plug up the ports on the head as well as the cylinders themselves when doing ANY type of cleaning... whether using sandpaper, gasket scraper, wire wheel, or otherwise - and vacuum out the ports or cylinders after you're finished.

I noticed that too, but if you look at the flange closer to the center, it seems the gap isn't there. Might need to adjust torque on that particular bolt.

Joecam18

Just a shadow I went back and checked. Now tell me about any gaskets that go between the header and the down pipe/pre cats

Joecam18

https://www.youtube.com/watch?v=XnKV...ature=youtu.be

This is where im at so far. Got some exhaust flange gaskets ordered for between the headers and pre cats because it sounds like a tractor at the moment lmao