We are still working away on our FB, it does start hot or cold easy and sounds good but I wish to do a compression test with the correct tool to get readings.
What is the acceptable compression obtained hot and cold for an 82/83 Fb. I am new to rotary and believe the readings need to be "calculated" too??
compression readings
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rustyrescue
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ian65
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Re: compression readings
If you get it tested with a proper rotary compression tester if will automatically calculate the readings for you and give you the compression test figures.
As a rough guide... readings in the 8's = great, 7's = very good, 6's = good/ok, 5's = low-ish, 4's = very low.
Having said that, if it starts well hot and cold then don't worry about it. They can go for ages even with low compression.
I took a stock 12a from a car that had been stood on someones drive for 20 years, it had done 96,000 miles...., I put an Elford Turbo on it and continued to wring its neck for another 2 years until it gave up the ghost...... even tired engines can soldier on for years.
These are the readings from when I did mine last year...
viewtopic.php?f=4&t=27&start=130
.
As a rough guide... readings in the 8's = great, 7's = very good, 6's = good/ok, 5's = low-ish, 4's = very low.
Having said that, if it starts well hot and cold then don't worry about it. They can go for ages even with low compression.
I took a stock 12a from a car that had been stood on someones drive for 20 years, it had done 96,000 miles...., I put an Elford Turbo on it and continued to wring its neck for another 2 years until it gave up the ghost...... even tired engines can soldier on for years.
These are the readings from when I did mine last year...
viewtopic.php?f=4&t=27&start=130
.
1999 Jaguar XJR V8 Supercharged
1992 Peugeot 205 1.9 GTI
2003 Mercedes SLK 200 Kompressor
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rustyrescue
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Re: compression readings
ok, well tested now.....car unused for over 20 years and barely run. Warm engine, 5 readings 6 plus, other was 5.5. I will do it again when its run for a bit.