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

As always, remove all spark plugs while the engine is cold especially with the aluminium block.

The threaded body of #5 spark plug was covered in oil and it smelt awful compared to rest of the cyl.
Also, #1, 2, 3, 5 cyl spark plugs were showing sign of moisture corrosion addition to the light brown corona arching so definitely going to replace all of the six spark plugs this time.




Honda changed the heat rating from #6 to #7 at around 2000 models but then went back to #6 later.
Even with the modified engine using the high lift camshaft, it still uses heat rating #6 spark plug so no point in using #7 for the standard OEM spec engine.

In Japan, several engines using heat rating #7 with frequent short distance journeys reported misfire so not recommended.
For AT models, unless using manual shift mode always, it is very likely to be using lower rpm band so Honda Japan even switched to heat rating #5.

As this NSX is full OBD2 spec MT model, I recommended the owner to use PFR6L-11 instead and he brought the new plugs so will be using them.




In the process of compression check.

Data has been sent to the owner through email.

Interesting to see #3, 4, 5 cyl were 10psi lower than the rest of cyl and consistent result.
Will check the cam timing and existing valve clearance before backing off the adjuster.






Damages to the interior panels and using the wrong spec screws.




Not sure about this but it almost looked as if the little friend was living inside the cabin for a short period.....