Can one explain the reason behind reversing the lobes for cyl 4, 5 and 6?

That's very interesting.

Cheers, Wizard

Cylinders 4,5 and 6 are in mirror image to 1,2 and 3. The layout from front to back is
EI EI EI IE IE IE. The back three have to be mirrored to the front 3. At least that's what I take it to mean.

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David Kight
'62 Valiant Signet, White
'98 Dodge Dakota
'06 Jeep Liberty

Growing older is unavoidable but growing up is strictly optional.

Did the Toyota casting take to welding? The ls1 is 356 alloy that welds really well. I actually used a large press to remove warpage incured while welding. No cracks or damage.

How did the bore spacing work out, any overlap? Did you cut and join two sections or three?

While searching around for 4" bore spacing heads I came upon the DOHC Northstar/Aurora engine. The Aurora is 87mm bore so it's valves would fit down a slant cylinder. They use 4 bolts per cylinder too.

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Joshua

Don't forget the classic Jaguar inline six. It also has a 4 inch bore
spacing. There are four bolts around each cyclinder, but the
pattern is slightly wider to allow for the overhead cams. The
water jackets in the example I saw was in the same place but probably not the oil passages.

Is it time for the annual winter aluminum head thread yet?

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Official Cookie and Mater Tormentor.

Its summer here......

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Richard (aka Fingers)

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Official Cookie and Mater Tormentor.

I believe so

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Chris'
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