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Old 01-11-2026, 10:49 PM
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shaker455 shaker455 is offline
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Join Date: Feb 2002
Location: NH
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Quote:
Originally Posted by grandville455 View Post
Was this originally a 750 cfm Q jet and you ground the rings off, changed the booster design and milled out the ring in the venturi and it still wasn’t as good as the stock 71? So was the WOT better than the 71? What do you use to get inside there to grind that ridge out? Do you think taking the ridge out it lost velocity? Thanks!

You can read earlier post for your questions:
Post #1 outlines parts used
Post #35 milling machine
Post #76 base plate throttle bore resizing, milling machine
No mods to venturi shape
When outer ring is removed drastic signal loss
Area was much larger than a 455HO casting so signal loss maybe greater
Definite increase in area WOT, others who have done this mod street & strip can confirm
Goal was to regain some signal strength to match the 455HO while gain primary airflow and low speed drivability
This lead to three other approaches that I started to experiment.
If you take a try post up your results
Thanks

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Last edited by shaker455; 01-11-2026 at 10:58 PM.