You're talking about a manual trans right? If you want to maximize performance, put your foot to the floor and don't shift till at least 5,500 rpm. If you are in 3rd by 30 mph you're not trying very hard. I don't think an oversized carb is your problem.
Downsize Carb?
Thread Starter
Drifting
Joined: Dec 2008
Posts: 1,336
Likes: 169
From: Westampton New Jersey
Downsize Carb?
Im running a SB 350 bored out to 355, Edelbrock RPM heads, RPM air gap intake. Putting out about 390 hp. Im using an Edelbrock Thunder series 800 carb, Im really not getting much low end torque or speed till I get up to about 30mph. Almost 3rd gear out of 5. Very sluggish. Thinking maybe downsizing the carb. to a 650 for better response. OPINIONS? SUGGESTIONS?
Burning Brakes
Joined: Apr 2007
Posts: 1,039
Likes: 62
From: Kona Hawaii
Using a 600cfm carb from Summit.Here's my review:http://forums.corvetteforum.com/c3-t...or-review.html
Video:http://forums.corvetteforum.com/c3-t...arb-video.html
750cfm VS might be a good option for you.
Video:http://forums.corvetteforum.com/c3-t...arb-video.html
750cfm VS might be a good option for you.
Pro
Joined: Jun 2004
Posts: 692
Likes: 69
From: Juneau AK
Im running a SB 350 bored out to 355, Edelbrock RPM heads, RPM air gap intake. Putting out about 390 hp. Im using an Edelbrock Thunder series 800 carb, Im really not getting much low end torque or speed till I get up to about 30mph. Almost 3rd gear out of 5. Very sluggish. Thinking maybe downsizing the carb. to a 650 for better response. OPINIONS? SUGGESTIONS?
kdlp
Instructor
Joined: May 2008
Posts: 153
Likes: 0
Im running a SB 350 bored out to 355, Edelbrock RPM heads, RPM air gap intake. Putting out about 390 hp. Im using an Edelbrock Thunder series 800 carb, Im really not getting much low end torque or speed till I get up to about 30mph. Almost 3rd gear out of 5. Very sluggish. Thinking maybe downsizing the carb. to a 650 for better response. OPINIONS? SUGGESTIONS?
CF Community Team
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If you don't live over 6,000 RPM's you could very easily downsize your carb to a 650 and perhaps gain some low and midrange torque (as long as you have no other issues). I bolted on a 650 Holley spreadbore on my 68 427/390 and it makes loads of low and mid range torque and pulls strong right up to 5,500 RPM's. You may get more responsiveness throughout the RPM band and better volumetric efficiency with the smaller carb.
Le Mans Master
Joined: May 2002
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From: Lebanon Township New Jersey
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