FJ40 Mark/Downey Header

[Bad1975]

Only two options I can see unless moving it onto the header itself. The second towards the frame would make install and removal difficult. The flywheel cover and bell housing mounts interfere with vertical mounting so you have a 305 ish degrees or 75 ish degrees (more of and OEM angle). It’s quite protected being between the oil pan and flywheel cover from trail debries.

 

[Advrider639]

I’ve been out of the loop for a while… glad to see this across the finish line.

Placing order now!

 

[PabloCruise]

I’ve been out of the loop for a while… glad to see this across the finish line.

Placing order now!

Fantastic!!!

 

[Green Bean]

Very much looking forward to installing on our 400 series. @gonzopancho and @PabloCruise: Are we still looking at approx 16 weeks out for the exhaust kit?
Thanks!

 

[PabloCruise]

Only two options I can see unless moving it onto the header itself. The second towards the frame would make install and removal difficult. The flywheel cover and bell housing mounts interfere with vertical mounting so you have a 305 ish degrees or 75 ish degrees (more of and OEM angle). It’s quite protected being between the oil pan and flywheel cover from trail debries.

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Fantastic - thank you!
I am wondering where you are going to run your wires for the O2 sensor? Up the passenger side of the firewall?
Are you pleased with your access when it comes time to change out the O2 sensor?

 

[Bad1975]

Fantastic - thank you!
I am wondering where you are going to run your wires for the O2 sensor? Up the passenger side of the firewall?
Are you pleased with your access when it comes time to change out the O2 sensor?

My wires run right up to the bell housing mount and behind the throttle cable to the sniper plug. Access is easy in the position shown with a O2 sensor wrench.

 

[PabloCruise]

Only two options I can see unless moving it onto the header itself. The second towards the frame would make install and removal difficult. The flywheel cover and bell housing mounts interfere with vertical mounting so you have a 305 ish degrees or 75 ish degrees (more of and OEM angle). It’s quite protected being between the oil pan and flywheel cover from trail debries.

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Another question - @gonzopancho is orienting his O2 sensor like this on a '78 Pig.
I can't tell what is going on with your second picture, but would you be able to orient yours like this?

One thing I wonder about this is how much throw you will have w/ wrench or crow's foot...

 

[PabloCruise]

My wires run right up to the bell housing mount and behind the throttle cable to the sniper plug. Access is easy in the position shown with a O2 sensor wrench.

So they double back to run up the driver side?

 

[Bad1975]

It looks doable but more difficult to install and remove.

Should be able to see the wiring in these photos.

3rd pic is my much larger light where the O2 sensor would be oriented on the other side.

 

[cstav86]

Any opinions out there on heat from the headers cooking my factory power steering box? I have one of those in-line coolers and the box wears a heat shield. Just curious if it’s a ticking time bomb with added heat.

 

[Fe3]

Any opinions out there on heat from the headers cooking my factory power steering box? I have one of those in-line coolers and the box wears a heat shield. Just curious if it’s a ticking time bomb with added heat.

We would recommend keeping an eye on your temperatures. A hand-held IR temp reader can be useful for comparing temperatures at your steering box before and after header install.

Even with the factory exhaust, that location will be quite warm.

You might want to change to a larger power steering cooler.

 

[Bad1975]

Exhaust all finished up.

Sound clips in Facebook link

Log into Facebook - https://www.facebook.com/share/p/HemLTLxjABUfZP7k/?mibextid=WC7FNe

 

[theSherpa]

Exhaust all finished up.

Sound clips in Facebook link

Log into Facebook - https://www.facebook.com/share/p/HemLTLxjABUfZP7k/?mibextid=WC7FNe

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Link seems to be broken?

 

[Bad1975]

Should work now

 

[FJROSS]

Any news on the balance of the exhaust system? Time line?

 

[PabloCruise]

Any news on the balance of the exhaust system? Time line?

Sorry for the delay.
I don't have any updates.
This has been a week full of illnesses, putting out product at the day job, and delays from the manufacturer.
Apologies the exhaust is taking so long, I wish we could at least take pre-orders!

 

[Green Bean]

Ever since we acquired the truck, it had an old rusty set of headers with an unsightly exhaust that dipped too far down. I always felt that these really let down the overall appearance:

When the newly released Mark’s/Downey header became available, we purchased one. I had really hoped to get the complete exhaust kit so that I could do the "Plug-&-Play" installation in our tiny garage. But the time frame for the release of the exhaust kit didn't work out. So, I decided to let a pro do the installation since my welding skills are not that great and I've never tried welding with stainless. There are not any exhaust shops nearby, but I was fortunate to find a custom fabricator in Houston. I decided to have the vehicle flat towed to Aaron's shop.

For the installation of the header, I purchased new OEM manifold studs, nuts and washers:

90116-10042 Bolt Stud $1.79 8 $14.32
90170-10199 Nut Hexagon $1.67 8 $13.36
90201-10283 Washer Plate $1.03 8 $8.24

At his shop, Aaron paired the headers with a 2" stainless custom exhaust; a 1140 Vibrant Performance Resonator; and a 11234 MagnaFlow Muffler.

Although our 1970 truck did not come to us with either a skid plate or a rear heat shield, these were purchased a while back. I cleaned them up and painted them with Eastwood Extreme Chassis Black. Aaron mounted the resonator above the skid plate and the rear heat shield above the muffler. The heat shield was mounted with M8 nutserts and a bracket that he fabbed up.

The truck is scheduled to make the return trip on Monday so I've not yet heard the truck with the new exhaust.

 

[JKIII FJ40]

in hindsight, as he was mocking up yours, you could've made another one and sold it in an instant, awesome work!

 

[PabloCruise]

Ever since we acquired the truck, it had an old rusty set of headers with an unsightly exhaust that dipped too far down. I always felt that these really let down the overall appearance:
View attachment 3660514
View attachment 3660515

When the newly released Mark’s/Downey header became available, we purchased one. I had really hoped to get the complete exhaust kit so that I could do the "Plug-&-Play" installation in our tiny garage. But the time frame for the release of the exhaust kit didn't work out. So, I decided to let a pro do the installation since my welding skills are not that great and I've never tried welding with stainless. There are not any exhaust shops nearby, but I was fortunate to find a custom fabricator in Houston. I decided to have the vehicle flat towed to Aaron's shop.

View attachment 3660528

For the installation of the header, I purchased new OEM manifold studs, nuts and washers:

90116-10042 Bolt Stud $1.79 8 $14.32
90170-10199 Nut Hexagon $1.67 8 $13.36
90201-10283 Washer Plate $1.03 8 $8.24

At his shop, Aaron paired the headers with a 2" stainless custom exhaust; a 1140 Vibrant Performance Resonator; and a 11234 MagnaFlow Muffler.
View attachment 3660530

View attachment 3660531

View attachment 3660532

Although our 1970 truck did not come to us with either a skid plate or a rear heat shield, these were purchased a while back. I cleaned them up and painted them with Eastwood Extreme Chassis Black. Aaron mounted the resonator above the skid plate and the rear heat shield above the muffler. The heat shield was mounted with M8 nutserts and a bracket that he fabbed up.

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The truck is scheduled to make the return trip on Monday so I've not yet heard the truck with the new exhaust.

That looks great Green!
I am sorry the timing didn't work out...

 

[PabloCruise]

Ever since we acquired the truck, it had an old rusty set of headers with an unsightly exhaust that dipped too far down. I always felt that these really let down the overall appearance:
View attachment 3660514
View attachment 3660515

When the newly released Mark’s/Downey header became available, we purchased one. I had really hoped to get the complete exhaust kit so that I could do the "Plug-&-Play" installation in our tiny garage. But the time frame for the release of the exhaust kit didn't work out. So, I decided to let a pro do the installation since my welding skills are not that great and I've never tried welding with stainless. There are not any exhaust shops nearby, but I was fortunate to find a custom fabricator in Houston. I decided to have the vehicle flat towed to Aaron's shop.

View attachment 3660528

For the installation of the header, I purchased new OEM manifold studs, nuts and washers:

90116-10042 Bolt Stud $1.79 8 $14.32
90170-10199 Nut Hexagon $1.67 8 $13.36
90201-10283 Washer Plate $1.03 8 $8.24

At his shop, Aaron paired the headers with a 2" stainless custom exhaust; a 1140 Vibrant Performance Resonator; and a 11234 MagnaFlow Muffler.
View attachment 3660530

View attachment 3660531

View attachment 3660532

Although our 1970 truck did not come to us with either a skid plate or a rear heat shield, these were purchased a while back. I cleaned them up and painted them with Eastwood Extreme Chassis Black. Aaron mounted the resonator above the skid plate and the rear heat shield above the muffler. The heat shield was mounted with M8 nutserts and a bracket that he fabbed up.

View attachment 3660535
View attachment 3660537
The truck is scheduled to make the return trip on Monday so I've not yet heard the truck with the new exhaust.

And wow, that header really hangs down a far ways!

Nice parts list - thank you for posting that.