My Long Tube header build

[xnamerxx]

I might just take you up on that offer. Any idea how long the car is going to be down for service?

[tooter]

Originally Posted by xnamerxx

I didn't borrow from any existing designs, but with the given lengths I need to work with it just happened to follow their design.

I know. It's the available space that defines the shape, so all the headers are constrained to follow the same basic conforming profile.

When you get it done, post a video of how the engine sounds with the open header. I bet it'll sound awesome!

[xnamerxx]

I've got an ideal length to work with so in order to hit that ideal length while staying within the constrains of the chassis. My bends aren't quite as smooth as the DC since I've got to hit certain lengths so my bends snake a little bit which you don't quite see in the pictures.
I just decided to have the primaries terminate in about the same location as the stock header. The secondary is going to have some of that snaking as well just so I can get a few extra inches of tube length.

I'll make sure to give you a video after everything is said and done :)

[4/20 NEVER FORGET]

That looks awesome! Primary length looks fantastic.

Hey, quick question. How many wires does the secondary o2 sensor have? (the sensor after the 1st cat) Thanks!

[xnamerxx]

4

[tooter]

It looks like the tubing is oriented very nicely...

By the way, what mm inside diameter tubing are you using? And had you considered using twin runner bolt on connector plates similar to this one to make your header two-piece?

[xnamerxx]

The 2 halves will be flanged so it can be installed.
The tubing diameter is 1 3/8 for the primaries.

[malibuguy]

looks good. where are you going to locate the flex joints?

ive still havent decided if i want to build one as well, or go turblose. if the motor seems to respond very well to your header, i may stay n/a

[tooter]

Originally Posted by xnamerxx

The 2 halves will be flanged so it can be installed.
The tubing diameter is 1 3/8 for the primaries.

That's just about the same as the 36mm Weapon R tubing. I'm really curious how much you'll gain by the longer runners. You definitely have the principles of performance working in your favor.

[Bluevitz-rs]

I'm quite certain you're going to snap the header if you move the flex joint that far down the line. The reason the joint is where it is, is because of the engine movement. If you try and move it that far down, it'll either break away at the head or break the joint where the stock flex joint should be located.

[xnamerxx]

The stock motor doesn't have a flex joint, it uses a ball and socket joint. The reason the joint is located where it is stock is because that's the easiest and cheapest place to put it. There does have to be some flex in the exhaust and ideally it should be as close to the motor as possible but you work with the space you're given.
The exhaust itself is hung which allows some movement there so the only reason you even need flex in the exhaust itself is to reduce the wagging motion of the main pipe and reduce load from the header. If you look at the header there is a support beam the bolts to the block and the header and that's what's carrying most of the fore and aft load from the header which is another reason why the ball and socket is located where it is. I've done some analysis on this I have an idea of where the load is sitting. If the side bracket isn't in place all of the load will sit on the flange and the failure will be located on the flange, if the side bracket is in place the pipes are thick enough to handle most of the load but the secondary flange will still be taking some load under movement but its substantially less with the flex joint in place. So to get some flex I chose a flex joint over a ball and socket because its easier for me to incorporate it the multiple center section exhausts that I have.

[malibuguy]

Originally Posted by xnamerxx

The stock motor doesn't have a flex joint, it uses a ball and socket joint. The reason the joint is located where it is stock is because that's the easiest and cheapest place to put it. There does have to be some flex in the exhaust and ideally it should be as close to the motor as possible but you work with the space you're given.
The exhaust itself is hung which allows some movement there so the only reason you even need flex in the exhaust itself is to reduce the wagging motion of the main pipe and reduce load from the header. If you look at the header there is a support beam the bolts to the block and the header and that's what's carrying most of the fore and aft load from the header which is another reason why the ball and socket is located where it is. I've done some analysis on this I have an idea of where the load is sitting. If the side bracket isn't in place all of the load will sit on the flange and the failure will be located on the flange, if the side bracket is in place the pipes are thick enough to handle most of the load but the secondary flange will still be taking some load under movement but its substantially less with the flex joint in place. So to get some flex I chose a flex joint over a ball and socket because its easier for me to incorporate it the multiple center section exhausts that I have.

the motor mounts in our cars are incredibly soft & these motors go all over the place. a flex joint at the end of a 3-4foot long 'lever' would not be adequate.

to get an idea of how much front scratchers (FWDs) boucne about. go to your local test-n-tune with all the kids beating the fuck out their cars...its quite alarming.

the flex joint NEEDS to be located as close as possible to the motor to reduce the leverage on the rest of the exhaust, period. the further away it is, the less its able to absorb.

[xnamerxx]

Originally Posted by malibuguy

the motor mounts in our cars are incredibly soft & these motors go all over the place. a flex joint at the end of a 3-4foot long 'lever' would not be adequate.

to get an idea of how much front scratchers (FWDs) boucne about. go to your local test-n-tune with all the kids beating the fuck out their cars...its quite alarming.

the flex joint NEEDS to be located as close as possible to the motor to reduce the leverage on the rest of the exhaust, period. the further away it is, the less its able to absorb.

I've measured a touch over 2.5",on the rev limiter, of movement. With that being said it doesn't matter in my case since my roll mount will have been taken care of.

Yep, but you can't package a a flex joint in the location it needs to be in with joints that are a proper diameter.

[Viperoni]

Originally Posted by xnamerxx

I've measured a touch over 2.5",on the rev limiter, of movement. With that being said it doesn't matter in my case since my roll mount will have been taken care of.

Yep, but you can't package a a flex joint in the location it needs to be in with joints that are a proper diameter.

I've already got the 2-1 section of my header welded up, and it's mostly made up of a pair of 10" long, 1.75" ID flex pipes. Should allow for tons of flexibility, right where it's needed.

[xnamerxx]

Originally Posted by xnamerxx

it doesn't matter in my case since my roll mount will have been taken care of.

I'm not using the stock dog bone spring bolts flex joints are all irrelevant. The only reason I'm even considering a flex joint is to reduce exhaust noise slightly and help remove thermal growth caused by the catalyst.

My comment about the flex joint is that the bellows cause friction in fluid flow which causes turbulence which reduces flow. For that alone I wouldn't want to run them in my primaries where any slowing of gas flow can have drastic consequences.

I've done the math, run the simulations and calculated the load and stress points. I'm very confident in my design that I don't feel its going to suffer a fatigue failure.

[tooter]

Originally Posted by malibuguy

the motor mounts in our cars are incredibly soft & these motors go all over the place. a flex joint at the end of a 3-4foot long 'lever' would not be adequate.

to get an idea of how much front scratchers (FWDs) boucne about. go to your local test-n-tune with all the kids beating the fuck out their cars...its quite alarming.

the flex joint NEEDS to be located as close as possible to the motor to reduce the leverage on the rest of the exhaust, period. the further away it is, the less its able to absorb.

It took me a while to catch onto what you're getting at, malibu. It's like a lever. The farther away you are from the axis of rotation, the more movement there is. I'd never even considered this as a factor.

[cali yaris]

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