Thunda Babe

[WoodRay]

Going on a rough gasket volume of about 5cc it looks to be the right size in the dome if it's 15.6cc, but will physically check it all. It's bloody disappointing considering how much they cost. I will have to speak to them to see why they changed the inlet valve relief from the original design.

[WoodRay]

Well this engine has been a long slog. Today sees the cylinder head finished after massaging the chambers to get clearance with the pistons. The bores have also been relieved to allow for the exhaust valve overhang over the top of the bores. I only lost 1/2 a cc in chamber volume with the material removed from the head, but I also think it will allow better breathing in several areas around the valves, especially the exhaust valve. I think I have now discovered why Repco stated that these heads suffered with exhaust resonance in the exhaust at 4000rpm causing torque to peak at the same rpm.
All that is left is to check the cylinder volume again after relieving the bores. Pre checking I'm at 11.14:1 comp ratio. I may still have to skim the pistons down. Hopefully not.

[screwit]

Its looking to good to bolt together now .
Might need to make a coffee table for the lounge with a piece of glass on top of it .

[Bob Vic]

That is a work of art. I'm massively impressed!

[WoodRay]

Latest progress on my pistons removing piston valve shrouding. I'd decided any loss in compression related power will be negated by better scavenge breathing by removing all the shrouding edges that would affect flow across the top of the pistons from the inlet to the exhaust valve. My measured static compression ratio is now 9.9:1. I'll live with that. Shrouding on the inlet valve of the piston has to be removed by hand so it's slow going.

461191429_4052239841674640_4067264548160986428_n.jpg (172.28 KiB) Viewed 38 times

460463051_501770689355687_3739544380257408858_n.jpg (213.4 KiB) Viewed 38 times

[WoodRay]

Piston domes finished. Final balance tomorrow.

460410173_1274240403597438_1729344140828469278_n.jpg (109.46 KiB) Viewed 24 times

[Bob Vic]

Lovely work - you're a very patient man Mr Craig.