About forty thousand miles ago my mechanic warned me that my Toda cam gear's teeth were starting to wear out. Forty thousand miles later, when I completely forgot about the problem, my car dies and eats up about 10-15 teeth on the timing belt.

Everything was reassembled and it seems that the worn down cam gear teeth eventually weakened the teeth on the belt through vibrations and unnecessary friction.

Thankfully the engine passed leakdown with flying colors despite having sheared off so many teeth!

 

dam! thats some crazy stuff, scary to see after market stuff like toda fail.

 

how many miles did you have it for when he told you it was worn down?

 

that is weird. Did Toda change their cam gear design? My gears that I had from Toda were a modified factory gear....

Sorry, I have not modified my 97 ITR. I had the Todas in my 98 ITR, but that was 5 or 6 years ago.....

 

i didn't realize that cam gears were a wear-item =S

what timing belt did you use (toda, oem?), what kind of cams did you have in there, and how was your timing belt tensioner?

 

aftermarket timing belts (performance) eat up cam gears, stock belts are softer.

 

Yup. Which is why I don't use aftermarket used cam gears.

Also, did you have the toda belt?

I learned my lesson after a friends 210whp Lsvtec kept eating timing belts, replaced the old abused Crane Cam Gears with some new Skunk units and it's been holding it down ever since. It ate two timing belts within 10,000 miles. 10,000 miles later after the skunks, belt is fine.

I'd say you got lucky on the no bent valves part.

 

I was super lucky. It was a fortunate thing that I was just rolling in neutral when it slipped though.

I've been running stock everything with the exception of the cam gears. The timing belt, water pump, and tensioner were all replaced 40k miles ago with oem stuff.

I originally bought the car with the cam gears on it. The original owner couldn't recall when they installed the gears. But, it took about 40k from the time my mechanic told me that I *should* think about replacing it to the point of actual timing belt slippage. I recall that 40k miles ago you could feel a very slight curve to the point of contact of the gear and timing belt.

And it's funny because I never knew that cam gears were considered wear items either. My mechanic said that he's seen a few Toda/Spoon gears that have shown wear on the gears.

 

^ good to know. i'll have to keep an eye on my Toda cam gears/Toda belt as well.

i only thought that it was aggressive cams that shredded timing belts...now i gotta watch my cam gear as well.

redcoupe - you can't use OEM cam gears with aftermarket cams unfortunately

 

yes you can use stock OEM gears on aftermarket cams!!! you won't be able to degree or adjust them....but if you are building the engine you could degree the cams in with offset keyways.

 

over 60,000 on mine w/ stock belt and they look brand new...

 

good call, but you're right. what i meant is you "shouldn't" use cam OEM cam gears with aftermarket camshafts as you wouldn't be able to adjust the cams if your degree readings are out of wack.

btw, what's offset keyways? i thought you had to degree them in with adjustable gears? sorry for the noob question as i degreed my Toda B cams last weekend and it didn't think there was another way other than using adjustable cam gears.