Yep, that was an error I read through, and had to recheck.
Back then, I didn't like to say anthing on a post that had a lot of contractictory info. Silvolite cast alloy 4 cylinder posts and ring selections are contentious. Thats just because I saw 15 years of evidence from four people who have had problems with blow by and piston skirt loss, and I don't like telling excellent engine builders how to do there job.
Anyone who can make a 250 engine take 16 pounds of boost, well, they prove me wrong about Tempo/Topaz/Taurus replacment pistons, and I didn't want to be "that guy" who stops a sale. Its called slander or false witness if you don't have evidence. Its called a technicality if you do have evidence. Mustangaroo, his son Jason, Will/Kelly, parkwood60 and Brian here were enough for me to rule the 1185p and its replacements out, but each of these guys told differing details, and its most likely a ring and cylinder bore machining issue...or just giving a cast piston too many revs or too much boost. Will says a frozen wrist pin took out a cylinder wall, NOT the Tempo piston, so I believe him, but have a persoanl reservation.
In the old days, they TIG welded the oil slots and drilled holes like the European Touring Challenge Cologne V6 piston by Mahale.
Anyway, its easy to deck the iron head down to 80 to 90 thou to about 42 cc's to make up for it.
For the aluminum head, you can tig weld the chamber down like the closed chamber 144/170 head if you have to. By adding alloy via TIG, then machine back.
Talk with the engine builder about the right rings and bore texture.
Ian Tate from the Bathurst XU1 Torana days and his son in Australia wrote the book on bore texture and ring clearance, sumps and windage trays, and making cast alloy pistons, back in 73, 6500 rpm, 238 hp at 6500 rpm, 240 lb-ft at 4500 rpm, but by 1990, those same engines would last at 7500 or even 8000 rpm in 202 cubic inch engines. No forged pistons were ever used or needed.
11:21-12:21, and 19:24 to 20:00.
three 58DCO's from Maserati/ Ferrari with three 45 mm chokes. 10.3:1 compression on 97 octane leaded gas.
https://www.shannons.com.au/club/video/ ... otorsport/
http://www.gmh-torana.com.au/forums/top ... cam-specs/
Basically, what I'm saying is do your homework, and decide on performance, not cost.