|02-16-2008 06:09 PM|
From BG web site,
Tuning With Spacers
Spacers and plenum dividers provide an easy way to change the configuration and the characteristics of the intake tract and the relationship it has with the carburetor. Adding a plenum divider to an open plenum manifold can help keep the left to right fuel distribution balanced for oval track applications This is especially helpful on alcohol engines.
Using spacers between the carburetor and intake manifold can produce dramatic results. The use of a four-hole spacer can improve low end to mid-range by helping the carburetor draw and atomize fuel. An open center spacer increases the plenum area and can benefit the mid-range and upper rpm power. It is not uncommon to see combinations of spacer types or stacking of similar type spacers being used.
The actual results from any spacer or combination of spacers can only be measured during a test and tune session on the specific engine combination being run. This information can be a very useful tool when tuning to find the best horsepower or to change the power characteristics to suit a specific track condition.
|02-16-2008 06:00 PM|
If you have a 2-plane (180degree) manifold, using a 4-hole spacer will keep it a 2-plane manifold and may or may not help the fuel mixture make the turn into the manifold runners without crashing into the manifold floor and creating turbulence.
If you have a 2-plane manifold, using an open spacer will effectively turn it into a single plane (360 degree) manifold which may hurt bottom end cylinder filling and aid top end cylinder filling. Or not.
|02-16-2008 05:46 PM|
It's pretty hard to say ballpark statements about carb spacers. The only way to really know what your engine likes it to put them on a dyno.
|02-16-2008 05:20 PM|
|torrey||Sometimes a carb spacer will actually hurt your horsepower. From what I've read in magazines like Hot Rod, Car Craft, etc, most of the gains offered by a spacer are less than 10hp, usually only at the peaks. Each engine will respond differently, though, so you might pick up some noticable power with one.|
|02-16-2008 05:15 PM|
|NEW INTERIORS||It may help a little to keep the fuel a little cooler.But not enough to notice.In it depends on which carb you have for the open or four hole.|
|02-16-2008 05:07 PM|
does the 2 inch spacer have any advantage over a 1 inch? what is better 4 hole or open?