andrewtac
Well-Known Member
- Thread starter
- #1
I figured out why the cams were permanently locked at zero. The motor had several Dyno pulls, and a handful of street WOT hits. This occured when I lifted after a rolling burnout/WOT hit. It still ran, was able to drive on the trailer, and started it a few times trouble shooting. Vortech v13-94c, TKM bottom end, Livernois stage 3 heads, stock cams. Had comp stage 2 blower cams on, but was having phaser issues on the Dyno, went back to stock, oil pressure and phasers seemed to be working fine. On all the street WOT hits at high RPM the cams would revert to 0.0, and recover at some point either after lift or after a shift. I did not see this on the Dyno hits, however they were having issues on the Dyno setting it up for the th400/converter (seemed to blow through the Dyno) and I suspect it wasn't loading the car (numbers were way lower than they should have been).
After the hit where this occured, I reached out to Lund. They believed my valve spring pressure was way too high (Livernois springs significantly heavier than the pac springs). Ordered pac springs, new VCT kit, and some other things. Started pulling it apart, and found the damage.
I was running the MMR upgraded timing chains, that specifically state not to drag race, use a limiter, or have after market springs. All of those I did.
The primary chain appears to have ripped, and the exhaust VCT gear broke into several pieces (found all the pieces). Not sure how it happened though. Maybe chain jumped off the gear and wedged in there, caused both to break. I pulled off some of the cam caps on the exhaust cam, no signs of binding or metal in the oil. The crank gear is intact, no obvious signs of damage. The tensioner and guides don't look to have any problems. I think this occured nearly instantly. I checked the pistons, no valve contact or any damage. They must have immediately went to neutral when the chain snapped. Also, no signs of chain slapping around inside the timing cover or valve cover.
Plan is to pull the pan, make sure I have all the metal parts out. To get the VCTs I had to order an entire Ford timing kit. I am going to use the secondary chains from the kit. I bought some gt350 primary chains.
Should I reuse the MMR tensioners, flip kit, and guides? Or just go back to stock stuff? I think I have everything from the timing kit I ordered. Car should be 1300-1400ish with eventually some nitrous on top.
After the hit where this occured, I reached out to Lund. They believed my valve spring pressure was way too high (Livernois springs significantly heavier than the pac springs). Ordered pac springs, new VCT kit, and some other things. Started pulling it apart, and found the damage.
I was running the MMR upgraded timing chains, that specifically state not to drag race, use a limiter, or have after market springs. All of those I did.
The primary chain appears to have ripped, and the exhaust VCT gear broke into several pieces (found all the pieces). Not sure how it happened though. Maybe chain jumped off the gear and wedged in there, caused both to break. I pulled off some of the cam caps on the exhaust cam, no signs of binding or metal in the oil. The crank gear is intact, no obvious signs of damage. The tensioner and guides don't look to have any problems. I think this occured nearly instantly. I checked the pistons, no valve contact or any damage. They must have immediately went to neutral when the chain snapped. Also, no signs of chain slapping around inside the timing cover or valve cover.
Plan is to pull the pan, make sure I have all the metal parts out. To get the VCTs I had to order an entire Ford timing kit. I am going to use the secondary chains from the kit. I bought some gt350 primary chains.
Should I reuse the MMR tensioners, flip kit, and guides? Or just go back to stock stuff? I think I have everything from the timing kit I ordered. Car should be 1300-1400ish with eventually some nitrous on top.
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