Holley 750DP Bog
Thread Starter
Drifting
Joined: Oct 2005
Posts: 1,331
Likes: 479
From: Appleton Wisconsin
Holley 750DP Bog
I have the following engine 454, 10.5 comp. Edelbrock Alum 60459 heads, comp XE274 solids flat tappet, Torker II intake,Holley 4779DP,Tremec 5 speed, and 3:70 rear end. When I'am at 3000RPM and stomp the throttle I get a slight bog and black smoke out the back, I don't think the carb is too big It's a brand new one. Is this normal for a DP? Should I get a 850 DP? any ideas.
Instructor
Joined: Aug 2004
Posts: 166
Likes: 0
The black smoke typically means you are shooting too much full when you floor it. Try going to smaller squirters. That will slow down the timing of fuel delivered by the accellerator pumps. If you go down several step and it still does not fix it, you will want to try smaller accelerator pump cams.
All this assumes that the rest of the tune up is right. Try reading this article too. It is pretty informative on tuning techniques for Holley carbs.
http://www.bob2000.com/carb.htm
All this assumes that the rest of the tune up is right. Try reading this article too. It is pretty informative on tuning techniques for Holley carbs.
http://www.bob2000.com/carb.htm
Race Director
Joined: Apr 2000
Posts: 17,676
Likes: 201
From: Who says "Nothing is impossible" ? I've been doing nothing for years.
The size of the carb is not problem at this point. Find out what is causing it to bog before going out and spending money on new carb. A Holley 750DP is good for well north of 500HP. Fix the bog problem first, couple good ideas above, check for blown power valve, vacuum leaks, proper timing, proper jetting etc etc etc. A bigger carb ain't gonna fix that stuff 
