Puffwagon's Territory Adventures

[Tom Tucker]

Jesus. Haven't heard of a timing chain snapping randomly. Did you have a solid timing chain tensioner?

[Puffwagon]

It does a solid tensioner, however it still operates the same as the factory tensioner, it just has a locking stud behind it. I did it up the same as any other one, let it get it's place then give it an extra click. I checked it a couple of days ago and there was a little bit of give in the chain but not heaps. Perhaps the locking stud winds itself up over time? I'll check it with another chain when I get the timing cover off, I could remove the cam gears and refit them with the lock in place, if it won't go on then it could point to that. Maybe it just didn't need the extra click?

[Slowxr6t]

Man that sucks!! If it's too tight, does having enormous kws make it a worse problem or is having it a click too tight bad anyway? Now I'm getting paranoid cos I installed my atomic posi-lock tensioner. I feel for ya man, this territory adventure never fails to entertain your followers, good thing you enjoy it and can spin a spanner.

[Puffwagon]

Yeah I share it all, makes for a more complete adventure. Can't say that I enjoy having to fix it again after such I short amount of time, nvm the cost involved.

 

Each car is different with the tension that it'll settle at, before a click is added. You skim the head and the block enough times the cam timing will change and the tensioner will need more extension. It can sit between clicks if that makes sense, so may not need an extra click. Too tight is bad though.

 

I've never had an issue like this before but then again I've never built and tuned a barra to 1350hp at the crank. It might have even lifted the head and pulled on the chain like that, when it was fully turned up. The rev limit was set at 7600 with a 1 second +200rpm window, so it might have tagged the limiter once or twice, contributing to it. Maybe the variable cam timing was fighting it?

 

At any rate I'll be thinking about stuff and inspecting everything along the way to get an idea of what happened and how to prevent it in future. Now that I think about it, I should pull it down this weekend while everything is fresh in my mind, and also the engine state won't be changed from sitting for months.

[Tom Tucker]

Will be super interested on the post mortem

[Puffwagon]

Bent valves, possible damaged crank sprocket, possible chipping of piston crown coating and possible head /valve seat damage. We'll see on the weekend.

[Slowxr6t]

If I was near you I'd give you my spare atomic crank sprocket. Damn is it worth the heartache of having ginormous power?

[Puffwagon]

Cheers man.

 

Eh I still have my Honda so I'm all good. The territory will be back on the road soon enough and the bright side is, it doesn't cost any more to get 1mm OS valves over the 0.5mm I already have, so...free upgrade?!

[Slowxr6t]

More air flow thru engine! So it's a win.

[Puffwagon]

Haha I said this to the missus last night, she didn't agree lol