NB6C Engine into a NA6C

Discussions relating to Turbochargers, Superchargers, Induction, Engine Mods, Exhaust Mods, and other items specifically to make your MX5 or Roadster put out more power.

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Furai
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NB6C Engine into a NA6C

Post by Furai » Thu Sep 05, 2013 5:08 pm

So I did this recently.

Basically the B6-ZE out of the NB is better(Japanese spec anyway) because it has solid lifters for no more tick tick tick and it has higher lift cams giving it a little extra(125PS and 142NM compared to 116PS and 135Nm). Also easier to find in low Kms.

So you will need the engine.
NA8 Alternator.
NA6 Camshaft or a spare one to butcher,
Someone to butcher the cam and re weld it,

So basically use all of your accessories off your NA6 engine, that means the only thing you use from the NB is the block and head. I even used the NA6 cam cover.

So you need to remove the intake cam from both the engines.

Take the NA6 intake cam and then chop off the end piece where the CAS engages and attach it to the NB6 Cam.

You use an NA8 alternator because you need it to be ribbed not toothed belt. (Unless you use all of the front pulleys of your engine but it has to be a long nose).

You will have to remove the cap where the CAS goes but none of that is hard.

This is how NA6 engine looks.
Image

I dont have a pic of the cam but here is one with the CAS key in the NB cam.
Image

Dont forget to do the timing correctly :roll:
Image

Furai
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Post by Furai » Thu Sep 05, 2013 5:10 pm

Feel free to ask questions I can guarantee it wont make sense or I will have forgotten something...

SLYDIT
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Post by SLYDIT » Thu Sep 05, 2013 5:49 pm

so how did you work out at what angle to weld the cas end on?
i wonder if ti would be possible to lengthen the cas shaft to key into the NB cam??
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Furai
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Post by Furai » Thu Sep 05, 2013 5:59 pm

SLYDIT wrote:so how did you work out at what angle to weld the cas end on?
i wonder if ti would be possible to lengthen the cas shaft to key into the NB cam??
I marked the NA6 cam as the casting mark lined up with the cam pointing upwards then eye balled it and triple checked it before welding.

You might be able to but you would have to make some sort of key so the timing doesnt change anyway.

SLYDIT
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Post by SLYDIT » Thu Sep 05, 2013 8:03 pm

so i wonder if when rewelding the cas, you could alter the cam timing kinda like a exhintake mod? I.E move the cam wheel around to get a different cam duration , then weld the cas boss on the cam so it thinks its stock??
RED '90 TURBO.
SCARING PRIUS DRIVERS SINCE 2002

Furai
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Post by Furai » Thu Sep 05, 2013 8:42 pm

That would have the same effect as adjusting your CAS to set the timing which you have to do anyway.

Duration is by cam lobe so that wouldn't increase it, the exintake mod replaces the cam to get the extra duration.

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