Today at Atelier Kaz - ex-Honda R&D, F1, Indy/CART engineer

Just another data point.

Taking compression data at least once a year since new so 30th year now.

#1: 242, #2: 249, #3: 241, #4: 239, #5: 243, #6: 248 [psi]



Always amazes me with such consistent data over 30 years and for 175K miles.

Mine is JDM and odo kept in KM reading as I brought the car by myself when I moved to UK.






While in there, inspected the VVIS butterfly screws as well.


Original IG coils.

Driven in all sorts of weather condition.

Rear bank ones have some corrosion but not getting worse over many years so just keep using them.

Checked the spring tension as well.

May consider replacing all six cyl in the future while the OEM 2pin ones still available.

Then these original ones become the spare.





Evenly burnt spark plugs with corona arching brown marking at the insulator body.

No point in using Iridium or anything different from PFR6G-11 on MT with non-modified NA engine so just replaced with another set of same plugs.

I always source it from Japan through official supplier.

NGK has several factories around the world and there are so many fake ones on the market that hard to distinguish even using the engraved font, packaging, etc.

Don't want taking any risks for something exposed to inside of the cyl...



Due to sudden change in engine design at less than 1 year to go before official sale, Honda placed huge safety margin on our C30A engine.

No time repeating all the endurance testing at that point.

Thus, it can cover so many miles if looked after properly.


My TB/WP is into 13th year now and started to see the 1st sign of valve stem seal fatigue few years ago.

Next time when I can work on my engine, probably take the cyl heads off to replace the stem seal and re-condition the valve seating.


Will just keep driving as some NSX owners are now into 300K miles region and still happy with their car.



Kaz