Exhaust Manifolds | Warped

[El_Dude]

Will Remflex gaskets work with machined OEM exhaust manifolds? Or are OEM gaskets recommended?

Pretty sure they’ll fit as the exhaust holes are the same shape and the cutouts for the bolts are in the same place.

 

[HEMIMANN]

I was gonna put on Long Tube Headers, but finally backed down due to the expense versus the benefit, even though the benefit is substantial @ ~ +10% torque gain. The tuner I installed gives me the torque with the tow tune.

I've been putting off doing the manifold repair, I really should get this on the schedule with 46,000+ miles. I'm thinking about just re-machining the stock manifolds and adding remflex gaskets.

It takes the vehicle out of service for a time, so requires planning around.

 

[MartyZ]

Pretty sure they’ll fit as the exhaust holes are the same shape and the cutouts for the bolts are in the same place.

The Remflex is a thicker gasket. I dry fitted my gaskets with the old manifold before assembly and they overlaid perfectly.
All holes and shapes lined up.
Stud length on OEM studs is significant enough that you could definitely use the Remflex with stock parts if you went that route.

 

[UpstateNY2012]

First I'd like to thank everyone for posting all the helpful information in this thread. My 2012 1500 5.7 Hemi has joined the broken exhaust manifold bolt club and I', planning on fixing the problem myself. I'm relatively handy but don't have much automotive experience outside of brakes/rotors and oil changes. Before I get rolling I just wanted to ask a couple of questions for those that have done this job. I'll be replacing the manifold with AFE headers (Thanks Nick). I see many folks here recommending the Remflex gaskets and I'll be ordering a set from Summit Racing. Does anyone have any other recommendations? I would also like to replace the bolts that fasten the manifold to the exhaust. Can anyone point me to what part that might be - just trying to save a phone call.

As far as doing the work I've got a mig welder in anticipation of having a stud broken off flush. Are there any other tools/items I should have that might make this go a little smoother? Something you might have found you wish you grabbed before you started?

Thanks for any insight or help I appreciate it.

 

[MartyZ]

Does anyone have any other recommendations? I would also like to replace the bolts that fasten the manifold to the exhaust. Can anyone point me to what part that might be - just trying to save a phone call.

As far as doing the work I've got a mig welder in anticipation of having a stud broken off flush. Are there any other tools/items I should have that might make this go a little smoother? Something you might have found you wish you grabbed before you started?

Thanks for any insight or help I appreciate it.

Those are the bolts I used for my headers.
You may want to have a low profile cut off wheel or equivalent. If you see my thread on my project you will see I had to mutilate my old headers to get it off the broken stud. Strangest experience of my life. haha My buddy came through with a Dewalt cordless cut off, we used a wheel that was wore down pretty far and were able to get to down to the stud without grinding unwanted surfaces.
Also, grab some moving blankets or weld blankets. It makes cleanup much quicker if you end up up grinding the old ones off

 

[UpstateNY2012]

View attachment 520378
Those are the bolts I used for my headers.
You may want to have a low profile cut off wheel or equivalent. If you see my thread on my project you will see I had to mutilate my old headers to get it off the broken stud. Strangest experience of my life. haha My buddy came through with a Dewalt cordless cut off, we used a wheel that was wore down pretty far and were able to get to down to the stud without grinding unwanted surfaces.
Also, grab some moving blankets or weld blankets. It makes cleanup much quicker if you end up up grinding the old ones off

Marty,

Thanks for the reply. I was able to get the passenger side off without much work and have that side fitted up. I ended up with AFE shorty headers and purchased the remflex gasket in your picture (6022). What I noticed is the gasket and the headers don't line up perfectly - there is some overhang. I've attached a picture.
I verified with the company I purchased them from that they would fit but wanted to double-check. I'll most likely post a new question since this thread is much quieter. I appreciate any help!

Thanks!

 

[MartyZ]

Marty,

Thanks for the reply. I was able to get the passenger side off without much work and have that side fitted up. I ended up with AFE shorty headers and purchased the remflex gasket in your picture (6022). What I noticed is the gasket and the headers don't line up perfectly - there is some overhang. I've attached a picture.View attachment 521415
I verified with the company I purchased them from that they would fit but wanted to double-check. I'll most likely post a new question since this thread is much quieter. I appreciate any help!

Thanks!

Thats weird, i wonder if the face plate of the shortys is different than the Long Tubes.
Is there a chance the gasket is flipped or something?
Maybe a picture of the gasket on top of the manifold to see how everything else lines up?

 

[UpstateNY2012]

Thats weird, i wonder if the face plate of the shortys is different than the Long Tubes.
Is there a chance the gasket is flipped or something?
Maybe a picture of the gasket on top of the manifold to see how everything else lines up?

I've flipped them every way I can. Here are two more. When I ordered them I specifically told them the type of headers I was using and I was told they would fit...

I appreciate you taking a look.

 

[Hemi395]

Marty,

Thanks for the reply. I was able to get the passenger side off without much work and have that side fitted up. I ended up with AFE shorty headers and purchased the remflex gasket in your picture (6022). What I noticed is the gasket and the headers don't line up perfectly - there is some overhang. I've attached a picture.View attachment 521415
I verified with the company I purchased them from that they would fit but wanted to double-check. I'll most likely post a new question since this thread is much quieter. I appreciate any help!

Thanks!

Is that the passengers side? A lot of gaskets still have provisions for the egr valve on the pre vvt Hemis....

 

[UpstateNY2012]

Is that the passengers side? A lot of gaskets still have provisions for the egr valve on the pre vvt Hemis....

That's the driver's side. I fit up the passenger side last night but didn't secure it yet once I saw how the gaskets were fitting.

 

[PowersOf12]

I will say, I have had both the exhaust manifold cracked bolts (130K miles both manifolds) and the lifter/cam lobe failure on cylinder #8 (154K miles) on my 2012. My neighbor also had both problems on his 2013 similar mileage but two lifters were damaged. Both of us drove around 4000-5000 miles with the lifter failing and ticking loudly until the check engine light came on with misfires. He replaced his cam and lifters in a weekend for a total cost of $1500 with only YouTube to help, Dodge has mine right now under lifetime warranty. As far as exhaust manifolds, I would not replace them. I would remove them, grind them level and reinstall with new bolts and new gaskets because the new ones will probably just warp anyways. Good luck.

 

[huntergreen]

I was gonna put on Long Tube Headers, but finally backed down due to the expense versus the benefit, even though the benefit is substantial @ ~ +10% torque gain. The tuner I installed gives me the torque with the tow tune.

I've been putting off doing the manifold repair, I really should get this on the schedule with 46,000+ miles. I'm thinking about just re-machining the stock manifolds and adding remflex gaskets.

It takes the vehicle out of service for a time, so requires planning around.

Some folk say after machining, the manifolds won’t warp again.

 

[HEMIMANN]

Some folk say after machining, the manifolds won’t warp again.

True. Thermal cycling warps them into their set position. Bad design. If you machine or belt sand the surface it will seal again, permanently.

 

[LIFTED-]

If you have access to a Bridgeport Milling machine you can mill them yourself:
https://youtu.be/4wXK2xjk2EU

Took me a lot of time to set each one up and mill them flat, but they are much better now.
I can't believe how much they actually warped, hoping that they've taken their final shape and will stay relatively flat now.

 

[G-Ride990]

If you have access to a Bridgeport Milling machine you can mill them yourself:
https://youtu.be/4wXK2xjk2EU

Took me a lot of time to set each one up and mill them flat, but they are much better now.
I can't believe how much they actually warped, hoping that they've taken their final shape and will stay relatively flat now.

Looks like a nice setup in your profile pic. Coming from a journeyman machinist turned MFG engineer.

 

[HEMIMANN]

Makes me wonder if a belt sander can actually hog enough met to get them flat enough to stop leaking?

 

[G-Ride990]

Makes me wonder if a belt sander can actually hog enough met to get them flat enough to stop leaking?

Bet you can get them pretty close on a belt sander but not perfect like a mill. If you use some remflex gaskets, either one will be good enough I am sure.

 

[LIFTED-]

Makes me wonder if a belt sander can actually hog enough met to get them flat enough to stop lea

Bet you can get them pretty close on a belt sander but not perfect like a mill. If you use some remflex gaskets, either one will be good enough I am sure.

I ordered the Remflex gaskets.


I had to take ~20 thou off the outer ports, and like 50 thou off the center two to get them to clean up.

After milling, one manifold was pretty damn flat, the other I could fit a 3.5 thou feeler under one bolt hole ear.

If I didn't have the mill I would have belt sanded.

 

[G-Ride990]

I ordered the Remflex gaskets.
After milling, one manifold was pretty damn flat, the other I could fit a 3.5 thou feeler under one bolt hole ear.
If I didn't have the mill I would have belt sanded.

.0035 is better than any stock manifold out there I bet.

 

[EdGs]

I did the belt sander method, and I know I didn't get all the warp/twist out. I used fel-pro gaskets as well and haven't any issues as of yet.

I would have used remflex gaskets if I hadn't already gotten the fel-pros, though.

Great job, @LIFTED-.