New to the fourms and the 1989 festiva free spinning engine

[shortride]

I've been looking all over and cant find this bit of information.
is the 1989 festival engine a free spinning engine.

[william]

You mean like non interface? If so yes, If the t belt breaks no damage.

[shortride]

yes, thank you for the info, its good to know about the little things. been wanting a festiva
for as long time, finally one just fell into my lap.

[Advancedynamix]

Congratulations on your find! Let's see some pictures.

[2festi]

B3? I had one that snapped a timing belt and valves met pistons - hard. very hard.

[FestYboy]

No way, I had a b6 with a shaved head do the same thing and no valve damage... I propose something else failed to cause valve to piston connection.

[2festi]

yes way.

all my research had told me it was non-interference, so we were most surprised/shocked to open it up and see the damage.

crankshaft was ok, rods were ok. pistons slapped valves quite hard. motor was rebuilt with new valves and a timing belt and no problems....

it was at max rpm when it let go upon landing over a small jump (at a rallysprint), and it bent all 8 valves, and my engine bloke thinks this is why valves and pistons met - if it had been at low rpm, no worries, so he reckons.

what else could have failed to cause valves and pistons in a B3 to meet, and when we put in new valves and timing belt, allowed the engine to run (and still be running over a year later)??

[ryanprins13]

How would it hit all the valves though, even at high rpm? Once the belt beaks and the first valves hit should it not stop the camshaft from turning? The engine i took apart with a broken timing belt had the camshaft stop when the first valves hit on an interference engine. Rods stretch at high rpm but not very much, i cant think of anything that high rpm would do to cause the valves to come closer to the pistons.
Did it have a milled head or block or thinner head gasket?

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[FestYboy]

Ah, at high rpm, me thinks it would have been valve float in combination with the broken belt that caused the bending, or even more likely, the valves were being thrown off the tips of the rockers. I believe that's more plausible due to the fact that all 8 were bent. Typically when a belt brakes and valves are bent, it's only a few that take the damage, not all of them. I'll further support my claim as I purposely set my cam 4 teeth off just for giggles and ran the engine... No damage.

In any event, the b3 and b6 are both listed as non-interfierance from the factory.

[2festi]

stock motor - no shaved head or thin gasket.

our theory is at max rpm the crankshaft acted like a flywheel and kept spinning.
most timing belts snap upon first start up and low rpm.

a hot motor at max rpm in motorsport is a bit different to "normal use" I would suggest
I think Festyboy is on the money with valve float, high rpm, valves being thrown off the tips of the rockers...

fwiw the day was high 30's (so around 95 to 100F)

[monkeykiller1996]

got any pics I'd love to see the carnage

[2festi]

unfortunately not

all 8 valves were bent.
none of us could believe it either, after all, these are non-interference motors.
I gave the car to a local car club for the juniors because I/we thought it was just a simple timing belt fix (and I just go buy another $200 car to race).
I was extremely embarrassed when I was told it was bent valves.
I went and saw them myself - all 8 had bent stems.
we were all speechless.
all googling says non-interference!!

usually yes, but obviously not in extreme circumstances...