G'day Guys,

I'm about to put my 600cfm Spreadbore Holley onto a new Edelbrock Performer Dual-Plane Manifold.

The manifold has bolt patterns for Square and Spreadbore carbies, and there opening on the manifold is an open square(not an arrangement of four bore holes).

My question is this:

- It is an HX, and the inlet is heated by the exhaust, hence I am putting a 12mm Phenolic spacer between manifold and carby
- What type of spacer should I get?
- an open Square-shaped Spacer (not squarebore, an 1 large
square opening)?
- or a Spreadbore Spacer?
- On either spacer should I use a square shaped gasket between the spacer and intake, and the appropriate one (spread or squareshaped) between the spacer and carby)

Thanks Guys!

1976 HX Ute 308

Consider blocking off heat riser unless you live in South Island of NZ. Aluminium manifolds absorb heat quickly from under the bonnet, through bolts etc.
A cooler manifold gives you a denser intake charge which if jetted correctly will make more power, a

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Simmo
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Hey guys,

One more thing:

If i put a spreadbore gasket between the 13mm phenolic spacer (4 Barrel) and the manifold (dual opening, swuare shape), there will be a lot of the gasket that isnt between metal (i.e under spacer and opening of intake. Will

202 column 3-speed HX Kingswood ute made in the Pagewood plant (Sydney). Sierra tan metallic (1919) with tan trim (67V). VIN number will be 8N80LGH902770X, which simply reflects the rest of the plate's data.
The ADR27A red 308's also had exhaust heated v