Can a Rocket III take down the establishment, and rule this island

[DesertRat]

So in southern Ireland, drag racing isn't a big thing. In fact there is only 1 motorcycle event on per year here that I know of, it's on in early April on a public road which is closed for the day.
(There are no drag strips here. Only other drag races I know of are cars that do it on an airport runway that closes for the day.)
Anyway 10 years ago this was the final - two turbo Hayabusas, and about 8.88sec time being as good as it gets overall.

No Drag Strips In Ireland...

That's so Un-American.....

 

[DesertRat]

Finally got a little bit of time to throw the Robinson trans into the engine.
Also drowned the gear change actuator bolt with green high strength loctite for good measure, while in there.
Had it done before but why not re-do.
Buttoned it up with torquing the main bearing ladder and crankcase bolts.

Now to roll it over and pull the head.
Have to replace the titanium valve retainers and the cam timing gear on the crank nose that broke.
Aaaand inspect the pistons now that I'm tuned up to about 70% throttle and 6000rpm - and change them out for the slightly lower comp set I got custom made but are sitting there unused.

Among other things, I Love the Clean working environment.. Good work!

 

[DesertRat]

Power maths & plan

Effective final compression will be about 17:1 and I running our standard 95 RON fuel (southern Ireland sucks for motorsport, 95 RON is all we can get), a lot of ignition taken out so the power might be a bit less than 350 wheel.

I run VP Fuel for over 20 yrs..

They offer an extensive line of Performance Fuels, Ethanol, Unleaded, Oxygenated etc Octane rating ranging from from 94 to 110.

https://vpracingfuels.com/

There's a VP Fuel Dealer called Murrays Motorsports
Unit 9-11, Beechlawn Industrial Complex, Greenhills Road,
Dublin D12 VY54
Ireland

Hope this helps get you some 100+ Octane Fuel

 

[Gerald]

Finally got a little bit of time to throw the Robinson trans into the engine.
Also drowned the gear change actuator bolt with green high strength loctite for good measure, while in there.
Had it done before but why not re-do.
Buttoned it up with torquing the main bearing ladder and crankcase bolts.

Now to roll it over and pull the head.
Have to replace the titanium valve retainers and the cam timing gear on the crank nose that broke.
Aaaand inspect the pistons now that I'm tuned up to about 70% throttle and 6000rpm - and change them out for the slightly lower comp set I got custom made but are sitting there unused.

Serious times, and then soon serious fun time

 

[Bob R]

No Drag Strips In Ireland...

That's so Un-American.....

So is Rosie O'Donnell but there they are.

But all is forgiven because they do export some mighty fine sipping whiskey. Just not before the the ride!

bob

 

[R-III-R Turbo]

I run VP Fuel for over 20 yrs..

They offer an extensive line of Performance Fuels, Ethanol, Unleaded, Oxygenated etc Octane rating ranging from from 94 to 110.

https://vpracingfuels.com/

There's a VP Fuel Dealer called Murrays Motorsports
Unit 9-11, Beechlawn Industrial Complex, Greenhills Road,
Dublin D12 VY54
Ireland

Hope this helps get you some 100+ Octane Fuel

Thanks. You can order the stuff in alright here, when preparing for a track day etc.
Suitable for a situation where one would have a map for the road (and having to use pump fuel, where only 95 RON is available countrywide) and another map for organised racing where you could run race fuel.

 

[R-III-R Turbo]

Ok so got a few days off work and gonna try get this engine back together after sitting there in bits for a few months

Have to pull the head to replace the titanium retainers and also gonna change out the 8.2:1 pistons to the 8.0:1s.
One important job on the way is finding the missing tooth from the broken timing gear.

Can you spot it?

So after a bit of examination I think I know what broke the timing gear.
It was in the Stroker engine for several thousand trouble free miles and it didn't break.
So why did it break within 2000 miles when the Carpenter and TTS supercharger were fitted?
If the gear was just a dud then surely a random tooth would be the one to break.
But it was the tooth on the thinnest and therefore weakest point of the gear.
It just smacks of outward pressure like the crank expanded and cracked it.
Looking closely you can see a mark where the gear was pushed against the crank shoulder.

And if you look at the chamfer shape of the gear vs the radiused shape of the mating part of the crank.
Not shown here but the new gear won't go in quite fully to the shoulder because of this.

And couple this with the huge force the crank pulley mount puts inwards when you tighten up the big drive bolt.

I'm sure what happened was the gear didn't mate properly with the crank shoulder due to the different shape of chamfer vs radius, and the pulley mount had the gear pushed in on it hard (hence the mark).
The chamfered edge was being pushed hard against the radius, which acted like it was pushing outwards stretching the gear.
And there was no slight clearance there to allow for thermal expansion.
So while under this pressure the natural expansion of engine parts from the heat, well the crank expanded and cracked the gear.

So now I will sand the chambered edges of the new gear to make sure it mates nicely with the radiused shoulder.

 

[R-III-R Turbo]

For anyone that didn't spot it... I got lucky... jammed in behind the chain guide

 

[TURBO200R4]

Good find on the parts no matching up.

 

[Gerald]

Ok so got a few days off work and gonna try get this engine back together after sitting there in bits for a few months

Have to pull the head to replace the titanium retainers and also gonna change out the 8.2:1 pistons to the 8.0:1s.
One important job on the way is finding the missing tooth from the broken timing gear.

Can you spot it?

So after a bit of examination I think I know what broke the timing gear.
It was in the Stroker engine for several thousand trouble free miles and it didn't break.
So why did it break within 2000 miles when the Carpenter and TTS supercharger were fitted?
If the gear was just a dud then surely a random tooth would be the one to break.
But it was the tooth on the thinnest and therefore weakest point of the gear.
It just smacks of outward pressure like the crank expanded and cracked it.
Looking closely you can see a mark where the gear was pushed against the crank shoulder.

And if you look at the chamfer shape of the gear vs the radiused shape of the mating part of the crank.
Not shown here but the new gear won't go in quite fully to the shoulder because of this.

And couple this with the huge force the crank pulley mount puts inwards when you tighten up the big drive bolt.

I'm sure what happened was the gear didn't mate properly with the crank shoulder due to the different shape of chamfer vs radius, and the pulley mount had the gear pushed in on it hard (hence the mark).
The chamfered edge was being pushed hard against the radius, which acted like it was pushing outwards stretching the gear.
And there was no slight clearance there to allow for thermal expansion.
So while under this pressure the natural expansion of engine parts from the heat, well the crank expanded and cracked the gear.

So now I will sand the chambered edges of the new gear to make sure it mates nicely with the radiused shoulder.

Glad you stayed with it until you found the root cause and can reassemble with confidence of finding the reason.