Mazda Talk Forums

I would also be concerned about the steering shaft, judging by the LHD car, it looks like it may be low enough to not be a concern, but definitely another obstruction to work around. Going down with the header does seem like the hard way. Between Japan, Oz and the UK somebody must have done a DIY install. The A/C line will not be a problem as long as it is behind the heat shield, just can't tell exactly where it goes from your pic. I thought I would not have to undo the heater lines till I got ready to pull it out the top.

Had a customer, Nic Grossi, successfully install a Racing Beat header onto his NC Miata with AUTOMATIC TRANSMISSION. To the previous installation notes he adds:


To avoid the "check engine light" I used a RoadsterSport
mid-pipe and placed one O2 sensor in header and the other in the
mid-pipe behind the Cat. That mid-pipe comes with threaded hole already
so the installation is as easy.


>From all the forums I've read the main problem with the installation in
the automatic is that it vibrates and rattles against the bell housing
because it is larger in the auto trany. WRONG! In the automatic there
is a bracket that has a useless ear (used to route the clutch cable in
the manual) that can be grinded down and removed. Once that is done It
fits perfect.



I will provide many photos in the near future of exactly what I'm
talking about. I'm not sure that the average DIY mechanic should
attempt this installation because of the grinding down of the ear. I
would put the following verbiage in the description:



Fitment for an Automatic Transmission includes several extra steps and
can only be installed with a modification to a bracket attached to the
transmission bell housing. The modification requires the bracket
attached to the transmission is removed and the "ear" that extends from
the bracket is grind down so that it does not extend out beyond the bell
housing flange, then reinstalled. Those uncomfortable with this type of
modification should not attempt the installation.

THANK YOU! THANK YOU! THANK YOU! And thank you too Nic. I'm going to be placing my order and I was going to have them reworked. I started the "Headers on an automatic" thread at Miata.net and there seems to be alot of interest in this very issue. Spread the word!

UH, one question. Does this apply to your GoodWin header also?

JamesM wrote:UH, one question. Does this apply to your GoodWin header also?

Yep, same fitment issue...same need to grind off tab.

God Bless and good night.

Additional tips for those installing the Goodwin headers into a right hand drive (RHD) NC.

I fitted the GWR headers at home last night. 3½ hours to remove and 1½ to refit, from start to drive away.

I followed Brian’s recommended method but found that the RHD cars have an additional problem with clearance to remove the old system from the car, namely the steering column.

I removed the battery and battery box to gain access to the connection between the steering column and rack. There are two bolts either side of the universal joint. Loosen the bolt on the column and remove the bolt connecting the rack and slide the universal joint up the spline to disconnect the column from the rack. It then swings out of the way.

With the battery box removed you can get easy access to the alternator bolts. I found that I needed to remove the belt (use Brian’s method to ease tension) and remove both the rear bottom bolt and the top front bolt and loosen the front bottom bolt. When the old header is out you should refit the alternator and tighten up the bolts as it’s easier to do with no headers in the way.

I also needed to remove the front bolt on the lower half of the cat heat shield off the old system as the thickness of the bolt head restricts removal as it hits the back of the alternator when lifting the old headers out.

Reinforcing one of Brian’s tips. Make sure that you have a socket set that can get to bolts at odd angles in tight places. Do a check on the rear bottom head bolt before starting the job. I needed to use an off set ring spanner as my ½” flexible drive was too large. The bottom centre head bolt can be accessed from the wheel well using a couple of socket extensions clipped together.

The AC line wasn’t a problem. It is very soft and easily pulled out of the way.

I got full exhaust installed few days ago.

The header part took the longest.

While header still in place the mechanic slowly but shurely removed its 2 piece shielding (exposing a catalitic converter).



After thet heater rubber hose was disconnected from metal hose - only few drops of coolant escaped.
This allowed lifting original header almost seamlesly.

It was hard to remove studs from the original header (those that you screw midpipe to).
What eventually we did is to fix the stud very very hard into a metalwork "on table clamp" (like in a picture) and turn the header.



Installation of a new header went pretty fuss free.

Hope this helps,
Gennady

another tip for those looking to save time and knuckles. I realized this would make header install much easier after installing the turbo:

instead of messing with the alternator or scratching the car while taking out the old header and putting in the new one, undo the passenger motor mount bolt from the bottom (17mm), use a jack to tilt the engine to the drivers side a few degrees. This not only gives you precious room to swap headers but also gives you easier access to the bolts! Just be sure not to tilt too much so that you do not pinch the lines behind the motor.

mann wrote:another tip for those looking to save time and knuckles. I realized this would make header install much easier after installing the turbo:

instead of messing with the alternator or scratching the car while taking out the old header and putting in the new one, undo the passenger motor mount bolt from the bottom (17mm), use a jack to tilt the engine to the drivers side a few degrees. This not only gives you precious room to swap headers but also gives you easier access to the bolts! Just be sure not to tilt too much so that you do not pinch the lines behind the motor.

Great tip Mike! I just wish someone had posted it earlier.

Actually, from my experience you don't have to worry about pinching lines. Just jack it up til you get resistance, once the motor mount has been loosened ofcource.