CUTLASS SP2P carb options?

WanaBa442

G-Body Guru
Aug 5, 2017
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New England
So, been rethinking intake options for the Olds 260 as it comes out of hibernation in a few weeks.
Have a SP2P intake for it, new dual exhaust and a trans rebuild planned.
Looking at the SP2P I see it has a dual pattern carb mount on it.
SP2P.jpg
The Holley 390cfm carb has been recommended as a good unit for this application, but then I saw this from Holley:
"This carburetor is calibrated for use on V-6 and small V-8 engines. This carburetor is a “square” flange carburetor and should NOT be used with adapters on “Spread-Bore” type manifolds, since adapters on may affect cylinder-to-cylinder fuel distribution. "

So now what? The floor of the SP2P is so flat any carb will need a spacer plate for the linkage to clear the intake.
Anyone done this, or run a spacer under a 390 Holley? I would think getting the carb up off the intake would add some plenum volume and actually create a better transition from the carb discharge area to keep fuel in suspension better than a plop onto a flat intake floor?
Other than a custom tuned quadrajet, what's a guy to do?
There's this: https://www.summitracing.com/parts/mrg-1932
which would make the two become one.
 
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565bbchevy

Geezer
Aug 8, 2011
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Michigan
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Oct 14, 2008
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The 390 should work with less restriction on that SP2P intake than a factory 4 hole iron intake. Use the Edelbrock adapter, probably the best one available.
 

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