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  #1 (permalink)  
Old 04-22-2010, 02:11 PM
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Default 2x4 vs 1 carb

I have 2x4 intake w/450's on my 428...beyond the WOW...would a singe holley and a RPM intake perform better?
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Old 04-22-2010, 02:40 PM
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Perform better doing what? Single four will out perform dual fours at an auto cross or a tight twisty road race event. Dual fours might be better for a hill climb depending on cornering involved. Dual fours will outperform a single at Le Mans on the long straight away. I'd take duals over a single at the drag strip. On the street, the dual fours or single, your call.

In general, assuming intake manifolds are similiar design, the dual fours will make more horse power than the single four, in my opinion.
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Old 04-22-2010, 03:01 PM
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Center hung floats and the ability to use a Turkey Pan (for the looks alone) on the single outweigh the small horsepower gain that the duals give you, IMO.
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Old 04-22-2010, 03:17 PM
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Given no hood clearance or other constraints a single carb will make more total HP than a dual quad setup.

I'm running dual 4s myself. The WOW factor is more than worth what small amount of HP you'll lose. I'm running a pair of Quickfuel custom built 750s on a Tunnel Wedge intake on my 482.
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Old 04-22-2010, 03:27 PM
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Quote:
Originally Posted by patrickt View Post
Center hung floats and the ability to use a Turkey Pan (for the looks alone) on the single outweigh the small horsepower gain that the duals give you, IMO.
+1.

...may or may not give you.

I'm starting to sound like one of those old fuddy duddies, but the multi-carb musclecars of yesteryear had higher HP numbers than their single carb brethren, but the single carb cars usually beat their multi carb counterparts at the drag races.

Example: 1966 Corvette 427/425 HP (single carb) versus the 1967 Corvette 427/435 HP (Tri-power). Otherwise the same engine.

Disclamier: Every car, driver and engine are different.
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Old 04-22-2010, 04:02 PM
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Let me also throw in the fact that getting the linkage and synchronization on a single is a lot easier than on a double.
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Old 04-22-2010, 04:12 PM
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Unless you are running a drag specific intake, the single will in most cases out perform a comparably equipped 2-4 set up.. The bling is the thing. If you want the best performance a single is the way to go... I've run the trips and 2-4s and with the exception of the pure allure that a 2-4 offers, I think a single is better all around.
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Old 04-22-2010, 05:43 PM
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Quote:
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Let me also throw in the fact that getting the linkage and synchronization on a single is a lot easier than on a double.
roger that...
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Old 04-22-2010, 06:02 PM
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Over the last 45 years, I've run everything from a single two bb to 6- 2bbl including 3x2, 2x4, 4x2. IMHO, a modern single bbl on a modern intake will make more hp everyday. Depends on what you want.....hp or bling.
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Old 04-22-2010, 08:04 PM
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Quote:
Originally Posted by patrickt View Post
Let me also throw in the fact that getting the linkage and synchronization on a single is a lot easier than on a double.
Wow, I bolted my two 4"s on and maybe 15 minutes with a screwdriver done!
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Old 04-22-2010, 08:45 PM
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Sheeshh Mike, I thought I was only one on this thread that could do that. Come on guys setting up the linkage for dual carbs aint that tough.
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Old 04-22-2010, 09:14 PM
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Quote:
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Sheeshh Mike, I thought I was only one on this thread that could do that. Come on guys setting up the linkage for dual carbs aint that tough.
I won't tell anyone
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Old 04-22-2010, 09:41 PM
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I had factory duals (600cfm's) on the 67 Gt500. What a pain, however the motor at that point was worn out and so was the carbs. I ended up switching to a single four. Just easier to live with but the dual certainly had a bigger WOW factor! Of course these day carb shops can build you a single carb that would outperform two carbs.
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Old 04-23-2010, 09:25 PM
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I never said duels would out perform a single 4! all I said was setting up "new 2X4 is not that hard.
I am FAR form a pro, but are you sure they are 600 carbs? a lot of people tell me my carbs should be 600 but I believe 550 are correct?
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Last edited by Ibr8k4vetts; 04-23-2010 at 09:29 PM..
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Old 04-23-2010, 10:09 PM
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More carbs = More problems..
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Old 04-24-2010, 05:51 AM
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Assuming equally well developed and tuned packages regarding engine and intake...

The side hung bowls on a single four are a distinct advantage in a road race environment.

The dual quads will outperform a single in a drag race environment - the advantages are better fuel distributon and equallized runner length.

Unfortunately the cast 2x4 intakes available for the FE are essentialy replicas of 40 year old parts and leave a lot of potential "on the table".
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Old 04-24-2010, 06:45 AM
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All my dealings with multiple carbs and they always got changed out.My reason was off idle performance.Most all my battles were street and the single dailed in dbl pump was the only way to go.I do know friends running two fours that are very crispy just not for me.
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