The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

  • Update Your Password Today!

    We have implemented tools to identify member accounts using insecure passwords and will be locking those accounts until their passwords are updated. Don't get locked out of your account - update your password today, and ensure your account has a valid email address on file. Read more here...
Please Support RTM Racing
Please Support ExtremePSI

Spyder 1G NT Header on 2g Spyder GS 4G64

You read right. This thread will be informative on fitting the 1g NT to the 4g64 block.
Keep in mind that there really isn't much information out there on how to do this.
This will be an ongoing updated thread. It won't be a tut right off the bat!
This is an experiment not to SEE if it will fit, but MAKE it fit, If any modifications are needed to the head, they will be posted as well as which header set to buy.

For this I am using a dnamotoring 1g nt header (BALL JOINT BETWEEN COLLECTOR AND DOWNPIPE!) set that includes: header, j-pipe/collector/ and downpipe (2g is flexpipe, 1g is bent slightly, should work the same!)
I will also be using a DSG 2.25" catback (its nt bite me) and test pipe.

The reason for this is because my oem header has a crack in the weld in cyl 2 and is really rusted. Another reason is the test pipe on right now is 2" (smaller than oem) and I don't have a spot for the 1st o2 sensor, this will fix all these problems.

Note: use penetrant on your exhaust studs so you don't shear them!
You will be deleting your rear o2 sensor (you don't need it anyway).

I will be updating this thread on 1/4/13 to update progress, if not, completion.
Thanks for viewing and please support this, I'm a test dummy at this point.

UPDATE: I finished this project on the 4th, didnt get a chance to update til now.
i will now form this into a tutorial:

1) First step is simple, put pentrant on all the bolts of you exhaust up until your mid pipe (directly under the center of the car). Wait about 5-10 mins and remove your old header, collector, downpipe, cat, rear o2, & midpipe.

You must be logged in to view this image or video.

2) Clean up your exhaust ports and make sure theres no corrosion where the gasket will be.

3) Go ahead and get your new gasket & header put on. Note: a 1G header WILL fit! it may not seem like it will at first, but i assure you it will. The Technique for getting it on is to get the Left side on as much as you can, but make sure there isn't too much of an angle to where the flange gouges the studs! On the 2 14mm nuts on the bottom corners and the 7 12mm on the rest (top first). Tighten them down from left to right and they will slowly pull the header to the block.

You must be logged in to view this image or video.

4) Put the studs in the lower header flange and make sure you use thread lock or they may vibrate out (mine did). Put the gasket on the Collector and bolt it to the header (again use thread lock).
NOTE: If your car is lowered a lot, you may need to head the collector up and bend it right at its bend point because the collector sits slightly below where the side skirts do.

You must be logged in to view this image or video.

5) Put the the downpipe on using this: Put the flanges close together and from left to right it should be this order: Bolt head, Washer, Flange, Spring, Flange, Nut. Do the same for the other side too. Leave it sort of lose so you can adjust it.

You must be logged in to view this image or video.

6) Put your gasket on and connect the HighFlow Cat (Test Pipe(make sure the balljoint is tight enough to where the the weight wont drag it down)).

7) Put your midpipe up to the rear flange on your catback and make a measurement to where the the flange (cat) ends on the mid pipe. Make the measurement and then mark maybe 1.5" back to where you'll be cutting the midpipe.

You must be logged in to view this image or video.

8) Cut the midpipe at the 1.5" mark back you made and cut the flange off 1.5" back from the inside of the flange.

9) TIG Weld the the flange back on the midpipe, make sure you're atleast close to level (if its a little off the balljoint can to adjusted to compensate). You could also use a sleeve over the cuts and use 2 2.25" exhaust clamps (you need to force them on and squeeze the studs close to get the cup on)

You must be logged in to view this image or video.

10) Put everything back together and make sure you use threadlock! put the front O2 Sensor in the header spot and unhook the O2 harness from the stock position, run it up to the front and Congrats! youre done! be sure to tighten up the bolts every now again until they don't loosen anymore and youre golden!

You must be logged in to view this image or video.

You must be logged in to view this image or video.


  • 20130103_223338.jpg
    36 KB · Views: 241
  • 0102131524.jpg
    55.4 KB · Views: 247
Last edited:
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds