Hey guys, so here's what happened:

My car shut off on me while cruising down the highway just before winter started. I just got digging into my engine this past weekend to see what was wrong (after knowing the timing belt came through the upper-timing cover). I discovered that the intake cam on my Evo IX broke at the oiling holes.

Moving forward, I plan to replace my cams but want some advice. Right now, my car is a stock turbo IX, but I plan to upgrade to a FP Black or HTA35R sometime this year. What do you guys recommend for a cam... Is it worth getting GSC S3s, Cosworth M3s, or Kelford 288/280s? Or should I just stick with a smaller lift/duration cam? I have a fully built engine including full head work.

Also, are there any manufacturers that I should be aware of still producing cams that have this problem? Thanks!

 

If u just bought this recently from cosworth, they should be slapped.

 

No.. few yrs old. :|

 

Still cams should last significantly longer. How much engine damage occurred?

 

Not sure as of yet... Hopefully not much, but I wouldn't be at all suprised if I need to replace the valves.

 

i have Kelford cams and have no issues with them. Good luck getting this straightened out

 

This same thing just happened to me this wkend car turned off at 6500rpm.. Cause was a Snapped cosworth M2 mivec camshaft intake side. Exact same spot right at the oiling holes ur pics tell my exact same story timing belt cam through the top of the timing cover and cam gears touched as a result.. Gotta love that "cosworth quality"

 

Not sure of your head components but double valve springs and a kevlar timing belt on the tight side will definitely be able to break a mivec intake cam.

 

Using Double valve springs and a gates racing timing belt.. Standard oem tensioner

 

That is likely the cause of the break. I would only ever recommend progressive beehive springs kit as they put less pressure on the camshaft. I would have also opted for a OEM belt that may have allowed for more elasticity than the gates. Your auto tensioner could have also been to short (too short in its stroke) on top of everything else.

 

how old are the cams?

 

^^ close to 3 years old..

 

I don't mean to revive a year old thread for no reason but literally this exact same thing happened to me all the way down to timing belt eating through the timing cover, pictures are exact same. I'm also running dual Springs, so anyone running cosworths might want to look at this thread and be cautious with dual Springs vs beehives, and oem belt vs Kevlar.

 

This is a non-issue now and its isolated to Evo 9 intake cams. Here is the thread that explains why these intake cams are snapping.

https://www.evolutionm.net/forums/ev...snapped-5.html