Managed to take the car to the stealership today to get the seatbelt recall performed, Ordered a compression test at the same time to see how healthy the car is. Here are the results!

Quick question though, the FSM measurements seem to be completely different from the readings the dealership gave me on the printout...anyone have any info on this by any chance? Much appreciated!







The numbers just seem completely impossible according to the chart in the FSM, anyone mind providing some insight?

 

Maybe because the numbers are in kpa instead of psi

 

760KPA is 110 PSI which is excellent!
730 KPA is 105 PSI which is also excellent!

you are in good shape. if you arent premixing I would recommend it

 

Turbo vs NA might make a difference -NA have higher compression rotors. The FSM #s are minimums - higher is better.

 

Going off that chart, at 250cranking rpm and 105-110 PSI he is basically at the TOP of the chart.

Just a FYI, I also had a factory engine with 110 psi. 2 months later a coolant seal ruptured. Not trying to scare you, but apex seal failures are NOT the only way these can go. 30 year old rubber finally gave way

 

you're fine, now drive it like you stole it!

 

The chart is plotting minimum pressure vs cranking rpm, so his numbers exceeding the high range on the chart doesn't matter - his cranking rpm were almost bang on 250, the center of the chart, where 85 psi is shown as the minimum. His numbers are about where a fresh, but broken-in NA motor should be at sea level.

 

That's why I was slightly confused, those compression numbers are way off chart. The motor is at 107k, and to my knowledge none of the prior owners have rebuilt it. It's also an automatic =/. Idk if regular 13b's are like the auto 8's, but those things are carbon monsters. (only Rx7's i've owned have been five speed.)

And stupid me, I forgot to mention, its a GTU, so yes, N/A.

 

Oh i'm well aware. I've been into Rotary powered cars since about 2006. And yeah, I do premix in both the rx7 and my rx8. (Pettit Protek)

 

It probably has 3 piece apex seals. Whe I tore it down and could tell no one had ever been in there. Mine had 3 piece seals and after rebuilding and going to a 2 piece seal the compression dropped about 10 PSI (engine is still fairly fresh though)

The engine had 207,500 when it went. Apex seals were actually worn below their height limit. Good thing the coolant seal went because I think the apex would have rolled out of the groove soon.

 

at 107K its probably the factory engine, so its got another 100k to go until the water or oil seals die

 

You've looked in by build thread, haha. the oil seals are well past their expiration date...which is probably why the compression read like it did.

 

also consider more than the raw numbers. you have two values that are pretty close to one another and one that is higher. that make sense as two faces will share a seal.

the numbers outright look good. the variance isnt that big which is what you want.