Was at the dyno today, car started acting up so i pulled the timing covers to make sure the gears didnt slip. they didnt slip, but i found that both intake and exhaust gears were cracked in multiple areas around the adjusting holes. lucky for me they didnt let go and grenade the valves and pistons.

They have about 8000 miles and a few dozen track days on them. running supertech singles for most of them and maybe 2000 on supertech light doubles.




time to buy some toda gears!

 

Am I looking at less than 1 degree of valve offset? Are cam gears really worth all that?

Is there something that would make your miata an interference motor all the sudden?

 

yeah that's the exhaust cam. the intake side is at about 3 or so.

This motor is far from stock and very interference.

 

Every (built) engine is different.
My exhaust gear is currently set at zero, resulting in +2.5 degrees actual.

When scrapping the gear, any chance of getting one of the Allen screws, one of mine have a mangled Allen hole?

 

I've got a busted screw on mine too if you are interested in parting them out. FYI fidanza sells a whole set of nuts/bolts for these for about $13

Alternatively call fidanza and see if they will replace them. Mine have over 20k on them but that was with stock cams.. Now I will be keeping an eye on them.

 

HA! no way these piles of crap are going on my engine again. Ill let you guys know when i yank them off (likely in the next few hours)

 

God damn! In the grand scheme of things you got lucky to have caught them when you did.

You obviously need a set, what are you going with next time around? Toda maybe?

 

Yeah man, you said it.
First set of pulls were only to 6k rpm since the dyno operator wasn't reading paying attention to the actual rpm... and then when the car was strapped back on the dyno in the afternoon, the car stopped wanting to idle after a single pull... which lead to discovering this.

Especially good, since the second set of pulls were going to be 'till it hit the rev limiter. Scary.