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Old 12-13-2017, 07:23 PM
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unclescratch unclescratch is offline
Chief Ponti-yacker
 
Join Date: Aug 2003
Location: northwest Arizona
Posts: 506
Smile Tuning my 6910 Spreadbore Holley

Trying to be a good student here, Tom.

Carb is on a RAIV intake w/1-inch phenolic spacer, no heat riser in use, mild 462, 9:1 compression, HFT single pattern cam 228degrees 480 lift on 114 centers, Hooker comp headers. Floats are level, all settings are 'out of the box' correct except rear jets are #80 instead of 86. (Too scary to check WOT w/o a helper in car to watch gauges!)

In order to maintain a 'square' window @idle discharge, The throttle must be completely closed w/zero tension on the idle speed screw. I have opened the secondary throttle blades 15/16 of a turn from zero tension and that gives me a nice 750 RPM idle w/14.7 AFR. I have reduced the IFR's with a piece of .008" wire.

How am I doing ???