NA8 crank appearance

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jp928
Driver
Posts: 90
Joined: Sat Jun 26, 2004 4:48 pm

NA8 crank appearance

Postby jp928 » Fri Mar 11, 2016 5:00 pm

Just opened up a BP motor bought to rebuild. Not sure if the crank appearance is normal - all the counterweights have their outer edges machined, with some 8-10mm dia holes drilled a few mm deep (assume balancing drillings), and a couple of Very small drill marks - 2mm dia, less than 1mm deep. The cyl 1 counterweights have a couple of machined flats with numbers stamped in -2, K, 29.
Does this sound normal ?
Do the cams have any numbers cast or stamped on them normally?

thanks
jp 92 NA6, 96 NA8 with Turbo in a clubbie.

manga_blue
Forum Guru
Posts: 4897
Joined: Mon Apr 24, 2006 7:27 pm
Vehicle: NA8
Location: Moruya, NSW

Re: NA8 crank appearance

Postby manga_blue » Fri Mar 11, 2016 5:40 pm

OEM ones look like this.
Image

Image
’95 NA8

jp928
Driver
Posts: 90
Joined: Sat Jun 26, 2004 4:48 pm

Re: NA8 crank appearance

Postby jp928 » Fri Mar 11, 2016 6:18 pm

Thanks, that looks the same. Excellent!

jp

93_Clubman
Speed Racer
Posts: 11854
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: NA8 crank appearance

Postby 93_Clubman » Sat Mar 12, 2016 11:40 am

jp928 wrote:Do the cams have any numbers cast or stamped on them normally?

From memory '5A' is cast onto them.

manga_blue
Forum Guru
Posts: 4897
Joined: Mon Apr 24, 2006 7:27 pm
Vehicle: NA8
Location: Moruya, NSW

Re: NA8 crank appearance

Postby manga_blue » Sat Mar 12, 2016 12:08 pm

Inlet cam on mine has BP and 05 cast on opposite sides of the shaft between 2 and 3. Exhaust has BP and 06.
’95 NA8

93_Clubman
Speed Racer
Posts: 11854
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: NA8 crank appearance

Postby 93_Clubman » Sat Mar 12, 2016 2:31 pm

Must have been thinking of the NB8A:
Image
http://www.solomiata.com/Mx5Engine.html


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