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Re: Compression readings on 12A engine

Posted: Fri Oct 05, 2012 11:37 am
by rei99
Monday I take the Elford for test. In the afternoon, if all going ok, the clear blue with original 12A and update here g-l

Re: Compression readings on 12A engine

Posted: Mon Oct 08, 2012 1:35 pm
by rei99
Mazda dealer done this morning: 8.1 and 8.0 at the starter motor rpm (about 200).
They tell me so, but it looks very strange to me :roll: : for a 12A (with rebuild titanium tips) seems too high, now I've found one, I try to do myself until the car came back home (is there for the carb).

Re: Compression readings on 12A engine

Posted: Tue Jan 01, 2013 8:50 pm
by chc
I had JAZ tested in November 2012 with following results
Front - 6.6 - 7.0
Rear - 7.1 - 7.6
Had this done by Motorsport B (Queensferry) and very pleased with the findings h[b[

Re: Compression readings on 12A engine

Posted: Tue Jan 01, 2013 8:54 pm
by ian65
those are healthy results Cliff...... no engine teardown looming for you.

Re: Compression readings on 12A engine

Posted: Sat May 11, 2013 8:03 pm
by rei99
Finally done! I've the video, by now just the value 8-)

- Clear blue Mk. II, 72.000km about, 12A
Front: 7,1 / 6,8 / 6,9 kg/cm2 @ 250rpm.
Rear: 7,2 / 6,6, / 6,9 kg/cm2 @ 252rpm.

- Elford Turbo Mk. II, 71.141km (rebuild done declared from past seller), 12A Elford Turbo
Front: 6,9 / 7,2 / 7,2 kg/cm2 @ 247rpm.
Rear: 6,6 / 6,7 / 6,8 kg/cm2 @ 240rpm. II try: 6,9 / 7,1 / 7,1 kg/cm2 @ 254rpm.

- Black SA22C with 13B 4ports, 25.000 km
Front: 9,2 / 9,4 / 9,3 kg/cm2 @ 248rpm. II try: 9,3 / 9,2 / 9,5 kg/cm2 @ 239rpm.
Rear: 9,6 / 10,0 / 10,0 kg/cm2 @ 239rpm. (morning) II try: 8,9 / 9,4 / 9,2 kg/cm2 @ 241rpm. (afternoon)

With original Mazda tester.
Happy, all ok, incredible the value of the Black one :shock:

Re: Compression readings on 12A engine

Posted: Sat May 11, 2013 8:43 pm
by Chud
You gotta be happy with that!

Re: Compression readings on 12A engine

Posted: Wed Oct 29, 2014 9:38 am
by rei99

Re: Compression readings on 12A engine

Posted: Thu Oct 25, 2018 10:59 pm
by ian65
holy thread resurrection Batman! Just revisiting this thread from 2011 after discussing Petes awesome comp tester on the FB page and saw the test results for Keiths engine from 7 and 1/2 years ago.... I wonder what that engines putting out now that I've been running a turbo on it for the last couple of years?

Re: Compression readings on 12A engine

Posted: Mon Oct 29, 2018 11:18 pm
by myatt1972
Bloody hell was it that long ago :o :o :o