FJ40 Mark/Downey Header

[65swb45]

What does your exhaust guy think? He should have more experience than the average Joe on tailpipe placement. It’s not just cosmetic, or clearance to consider.

In my experience, the closer the end of the pipe is to the back corner, the more likely that the vortex behind the vehicle will pull the exhaust back in to the vehicle, especially if the back is open/top is off.

 

[DSRTRDR]

running the pipe straight back will pull all the exhaust right back in - it HAS to go out behind the rear tire

don't ask me how I know

[also, the closer the exhaust comes out behind the tire, the more hassle the emissions guys will give you, as they will have to finagle the sniffer cone on with the tire in the way . . . ]

 

[zidaro]

dump exhaust behind rear shock 45* down. no tire or spring concerns. or leave it as a slip fitting end att shock for user to finish

.......though i read comments above and that is a real concern

 

[GA Architect]

@65swb45 brings up a good point, and reminded me of what modifications I had to do to a new exhaust that was installed when I initially purchased my 40. In the photo below, you can see how the mechanic had the exhaust run a little more than 45 degree out the right rear corner.

However, with the top off, this configuration sucked too much exhaust fumes back into the drivers/passenger area.....so I took it to my local exhaust guy, and he knew right away what the problem was. Thus, he cut and ran it straight out the right rear side, just behind the wheel. This took care of most, if not all of the exhaust fumes.

 

[cstav86]

@PabloCruise so it will work for those of us that have not flipped our rear springs and run sub 33' tires? Please help me understand, but the way I read it is you are trying to solve for a problem that is likely isolated to only people that have oversized tires AND flipped springs? Which I would think would be a very small number.

 

[gonzopancho]

@PabloCruise so it will work for those of us that have not flipped our rear springs and run sub 33' tires? Please help me understand, but the way I read it is you are trying to solve for a problem that is likely isolated to only people that have oversized tires AND flipped springs? Which I would think would be a very small number.

Likely.

I think it will clear 33s in a stock location axle.

But this discussion is important as we’re about to place a large(r) stocking order and both material prices and lead times are going up.

 

[kunzma]

So is there a timeline for purchasing a kit?

 

[PabloCruise]

@65swb45 brings up a good point, and reminded me of what modifications I had to do to a new exhaust that was installed when I initially purchased my 40. In the photo below, you can see how the mechanic had the exhaust run a little more than 45 degree out the right rear corner.

View attachment 3608364
However, with the top off, this configuration sucked too much exhaust fumes back into the drivers/passenger area.....so I took it to my local exhaust guy, and he knew right away what the problem was. Thus, he cut and ran it straight out the right rear side, just behind the wheel. This took care of most, if not all of the exhaust fumes.
View attachment 3608365

Thanks for the comments.
You are running 32s?
Do you think a person could fit 35s on there w/o hitting the pipe?
Is your tailpipe exiting out the side as far back as possible? I need a minute to crawl through your build thread...

 

[PabloCruise]

running the pipe straight back will pull all the exhaust right back in - it HAS to go out behind the rear tire

don't ask me how I know

[also, the closer the exhaust comes out behind the tire, the more hassle the emissions guys will give you, as they will have to finagle the sniffer cone on with the tire in the way . . . ]

Thanks Claudia. No way to we want to run straight out the back.
We are trying to keep it as far forward as possible and get it right the first time.

 

[GA Architect]

Thanks for the comments.
You are running 32s?
Do you think a person could fit 35s on there w/o hitting the pipe?
Is your tailpipe exiting out the side as far back as possible? I need a minute to crawl through your build thread...

See if these help.

For clarification: Tire - 32x11.50R15, Rim - 15" OEM modified to 9" wide, Springs - OME medium CS001R, Shackle - OMEGS9

 

[PabloCruise]

@PabloCruise so it will work for those of us that have not flipped our rear springs and run sub 33' tires? Please help me understand, but the way I read it is you are trying to solve for a problem that is likely isolated to only people that have oversized tires AND flipped springs? Which I would think would be a very small number.

The side exit looks to work for those that leave their rear axle housing where Mr. T intended it to be...

Agreed - I don't know of too many other folk who have moved the rear axle back.

 

[PabloCruise]

See if these help.

View attachment 3608716

View attachment 3608717

View attachment 3608718

View attachment 3608719

For clarification: Tire - 32x11.50R15, Rim - 15" OEM modified to 9" wide, Springs - OME medium CS001R, Shackle - OMEGS9

Thank you for the pictures - beautiful 40!!

 

[rainingagain]

The side exit looks to work for those that leave their rear axle housing where Mr. T intended it to be...

Agreed - I don't know of too many other folk who have moved the rear axle back.

Here’s mine. Stock exhaust. Stock mounting bracket in the stock location. Springs fully extended. Mid 66 build date.

 

[PabloCruise]

Here’s mine. Stock exhaust. Stock mounting bracket in the stock location. Springs fully extended. Mid 66 build date.

View attachment 3608880View attachment 3608881

Thank you!

 

[CruisinGA]

I run flipped springs and 37’s/38’s. There is no way to get a pipe out between the tire and spring.
This setup, with a catalytic converter has no exhaust smell with the top off. Only thing I can figure is that the tire creates enough turbulence that the exhaust doesn’t get “pulled” back into the passenger area

 

[Dianna]

Correct that I have 31's, was thinking about going bigger after I get my PS installed but maybe not! This exhaust is perfection and I don't want to mess with it. The setup that you have configured fits stock FJ40's and people that modify their suspension know that other things are also affected. Just my opinion, but sell the stock exhaust and those of you with modified 40's can make the necessary changes to fit your specific mods. The people that need to update can post what changes they made and how they made them to help others. I think all of us who actually work on our trucks knows that nothing is really ever "bolt on!"

I have not been able to get my 40 out of storage yet, I have only managed one trip around the block. When it has been warm here, it's been raining. A huge storm is actually rolling through as I type this. Still plan to post up some sound for you all, exhaust sounds awesome

 

[zidaro]

Correct that I have 31's, was thinking about going bigger after I get my PS installed but maybe not! This exhaust is perfection and I don't want to mess with it. The setup that you have configured fits stock FJ40's and people that modify their suspension know that other things are also affected. Just my opinion, but sell the stock exhaust and those of you with modified 40's can make the necessary changes to fit your specific mods. The people that need to update can post what changes they made and how they made them to help others. I think all of us who actually work on our trucks knows that nothing is really ever "bolt on!"

I have not been able to get my 40 out of storage yet, I have only managed one trip around the block. When it has been warm here, it's been raining. A huge storm is actually rolling through as I type this. Still plan to post up some sound for you all, exhaust sounds awesome

exactly why i suggested making a slip fitting parallel to and past the muffler that allows any end user to add the final "oem" side exit location piece (and even rotate and trim it a bit if needed, or re-route as needed for a modded setup.
Me.... im stock rear currently, but will be changing it up significantly in near future, so im interested in a clean exhaust that is future-proof

One exhaust to rule them all

 

[cstav86]

Correct that I have 31's, was thinking about going bigger after I get my PS installed but maybe not! This exhaust is perfection and I don't want to mess with it. The setup that you have configured fits stock FJ40's and people that modify their suspension know that other things are also affected. Just my opinion, but sell the stock exhaust and those of you with modified 40's can make the necessary changes to fit your specific mods. The people that need to update can post what changes they made and how they made them to help others. I think all of us who actually work on our trucks knows that nothing is really ever "bolt on!"

I have not been able to get my 40 out of storage yet, I have only managed one trip around the block. When it has been warm here, it's been raining. A huge storm is actually rolling through as I type this. Still plan to post up some sound for you all, exhaust sounds awesome

I second selling the stock exhaust and let folks that have other setups tweak it to fit.

 

[PabloCruise]

UPDATES!

I have pricing for the header.

First, thank you all for your interest in our efforts.

Before I go further, remember what @gonzopancho said about labor and materials costs - they are "dynamic", so pricing may change.

Also, I am trying to get to Cruise Moab to show folks in the Cruiser community our header and exhaust concepts, but right now I am having fuel system troubles. So time is limited.

The header price is $1695.00. We have put a lot of time and effort into the design and execution of this, and I have sharpened a lot of pencils to to come up with the pricing.

To do things properly, we are going to set up a vendor account here on MUD and post the official thread for commerce in the Vendor Marketplace. I appreciate that Woody lets us do a little promotion in Tech, but we always want to do it right.

Stay tuned for more details about how to order, timing, and exhaust pricing.

 

[Fe3]

Fe3 is the TriMeki vendor handle here on ih8mud.

Here is our vendor thread listing particulars about the order process:

TriMeki 2F/F Stainless Steel Header & Exhaust System

Thank you for your interest in our header for the 2F and F engines. There are lots of details related to our development of the header and exhaust products here: FJ40 Mark/Downey Header - https://forum.ih8mud.com/threads/fj40-mark-downey-header.1267016/page-16#post-15222385 We are taking...

forum.ih8mud.com

Thank you all for your interest in the header and exhaust! We'll post more details, but we have spent a bit of time and effort getting to this point. We are convinced this will help your 2F/1F engine breath a little easier.