[Steve C.]

A fwiw for interest. I did some back-to-back dyno testing. The HSD intake with my HP950 carb and a 1/2" open spacer made 589.4 hp at about 5700 rpm on the dyno, this was on a previous pump gas 4.210 stroke 462cid street engine. With the same engine & carb my Victor intake with 1/2" carb spacer made 600.9 hp at 6000 rpm. Both intakes had a port entrance opening about 2.300" tall, and were properly port matched to the cylinder heads in use.

HSD / no carb spacer:
577.9 hp at 5700 rpm, 581.0 ft.lbs. at 4400 rpm.

HSD / 1/2" open spacer:
589.4 hp at 5600/5700 rpm, 589.0 ft.lbs. at 4600 rpm.

HSD/ 1" open spacer:
589.8 hp at 5700 rpm, 590.8 ft.lbs. at 4400 rpm

I know peak numbers don't express much, really need to look at the curve with each different spacer.

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