Header 2.0

[xnamerxx]

Well since the car is no longer an AutoX mobile, I figured it would be a good idea to revamp my existing heading into something that with a bit higher of a powerband.

Parts acquired.



Not the best welding but it'll hold.

[WeeYari]

[xnamerxx]

There will be a better picture of whats to come in the next few weeks.

Pictures show above the are yet to be built collector and merge bullet.

[CrankyOldMan]

I believe what's under the paper on the left is one of these: http://www.ebay.com/itm/1-75-ID-3-OD...-/151587826008

[Jason@SportsCar]

A Burns collector would have been less work.

Originally Posted by xnamerxx

Well since the car is no longer an AutoX mobile, I figured it would be a good idea to revamp my existing heading into something that with a bit higher of a powerband.

Parts acquired.



Not the best welding but it'll hold.

[xnamerxx]

Originally Posted by Jason@SportsCar

A Burns collector would have been less work.

Less work but a few hundred more $$$

[Jason@SportsCar]

Originally Posted by xnamerxx

Less work but a few hundred more $$$

But you can sell the header you have.

[xnamerxx]

Tacking slip fit together


Slightly better welds


Time to grind my welds

[Bluevitz-rs]

[xnamerxx]

And the collectors done, it would have looked nicer, but I ended up having to cut it open to weld a few spots I missed oh well.

[tmontague]

I'm curious as toh ow you're going to hook this up to the header and mid piper in replacement of the donut gasket. Nice work so far, looking forward to the finished product

[xnamerxx]

Its a slip fit, so it slides onto the ends of the header tubing then it simply gets bolted to stay in place, its a very common method to attach collectors. When the collector gets hot the tubes will seal themselves.

As far as the midpipe goes, I've got a pretty stiff dogbone bushing, so it'll probably get a flex pipe and a vband instead of the donut gasket. Since this is a racecar it no longer utilizes the stock midpipe which allows me to go up in tubing size and make a few more HPs.

[tmontague]

what header are you running? I'm assuming you cut off the donut gasket part of it and will slip the collector over it?

[xnamerxx]

I'm currently running a custom 4-2-1 header that I designed myself. The whole exhaust on this car is custom, my uses are a bit different than most.

When the car was an AutoX car, I needed to move the torque band down a so the car was more useful below 4.5k rpms which my current header does quite well, but it chokes the engine at higher rpms which isn't good for a road race car.

With my current engine setup, my toque band is completely flat from 1900-5600 RPM, then is falls on its face, which is great for a autox car with the stock rev limit but no so much for a road race car that revs to 7400 rpms.

[Jason@SportsCar]

Originally Posted by tmontague

what header are you running? I'm assuming you cut off the donut gasket part of it and will slip the collector over it?

Here is a pic of the one he helped build for me:

Collector slips over the tube, then a few bolts with lock nuts keep it from moving.


Even though I have the TRD side engine mounts, and a poly dog bone, I used a ball socket to connect the header with the rest of the exhaust. No gasket to worry about, allows movement, and no leaks. http://www.summitracing.com/parts/mpe-10743/overview/

[xnamerxx]

Made some progress on the flange. Ended up goofing and forgot to clamp the flange to the table, took my quite a while to deck the flange and correct the warp. Still have quite a bit of work but making progress slowly.

[xnamerxx]

So this is the 2nd header I've built, the first one was more or less optimized for autox, it did a very good job between 2-5500 rpms, but it simply can't handle the higher redline the car has road racing. I designed that using a formula from one of my old teachers, its probably not as accurate as pipemax but it was close enough and my peak torque was only 50rpms off what I expected it to be. That header was a 4-2-1 with 1.375 primaries at 15" long and 1.625 secondaries at 16" long. 4-2-1 headers are kinda funny since the secondaries length is more important for low rpm torque if my understand is correct.

Here is the old header coming out so the new one can be fit.



I like to start with the bottom tubes since everything falls into place after that. The lift at the office was being used for a work project so I had to measure everything laying on my back, what a PITA that turned out to be.




After playing the measure grind cut measure again game for a few hours I for the tubes close enough to tack weld them in place. It would have been nice to have a third arm while doing this, ended up with a bunch of ugly marks trying to get the metal tacked together.



All 4 tubes close enough for govt work



That's all she wrote for today, need to pickup a few more feet of tubing I should be able to finish it pretty quickly.

Sorry I didn't take more pictures, I ended up having to cram the last of the header build last night so I ended up focusing more on getting it done.


Started on the stepup primaries to 1.625, man taking this header on and off sure is annoying lol



Spent the a good 6 hours fitting welding fitting welding again lol. Don't have any pictures of this point in the build, sorry about that I had a very small amount of time to complete this project. I spent a good amount of time working on keeping the metal moving around to a minimum. This process is quite a bit of tack -> weld -> check fitment -> fixture metal -> weld some more -> test fitment again all in all this is probably the most difficult part of the whole build since everything has to be dead nuts close in order for the slip fit to work. In the end the header has been built, I had to move it over to the side of the tunnel so I could get a o2 sensor in there, those AEM sensors sure are big compared to the factory sensors.



One thing I wasn't really account for was the fact that my total header length is now roughly 18" longer than it used to be, which created some problems in fitment for the rest of the exhaust. I ended up having to cut a big portion of my resonator apart just to get everything to fit. My header now exists at about the same spot as my seat so its pretty far back on the car, initial drive, and the car feels much more meaty than it did before but the dyno will be the real tell. Off to schedule a dyno session.