356B T5 engine rebuild question

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Steve Douglas
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Re: 356B T5 engine rebuild question

#61 Post by Steve Douglas »

I measured 8 different A/B manifolds all measure the same 35mm at the lowest point, then I measure the head intake ports, Casting dates; 1956 - split head 35mm, '59 A 35mm, 61 B head 35mm, 2-63 B 36mm. C and 912s are bigger, 40mm

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Brian R Adams
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Re: 356B T5 engine rebuild question

#62 Post by Brian R Adams »

Steve Douglas wrote: Sat Aug 06, 2022 11:17 pm I measured 8 different A/B manifolds all measure the same 35mm at the lowest point, then I measure the head intake ports, Casting dates; 1956 - split head 35mm, '59 A 35mm, 61 B head 35mm, 2-63 B 36mm. C and 912s are bigger, 40mm
Sorry, my mistake. Pellow (p. 44) claimed a difference between A/B Zenith Super and Normal manifolds' valve ports, to wit:

Normal: _1.17" x 1.37" (29.7mm x 34.8mm)
Super:__ 1.20" x 1.40" (30.5mm x 35.6mm)

I kid you not, a 0.03" difference.
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