4 hole spacers move the tork band down in the RPM Range by increasing the venturi length and keeping the A/F mixture directional and holding the particles vaporized deeper into the manifold.
They improve idle signal and make low end tuning easier, offering a cleaner crisper idle and better off idle throttle response.
If you look at stock manifolds many are designed with a four hole spacer cast right into them. The top of the manifold on my 454 motorhome for example is about 1/2" thick creating a built in 4 hole spacer and increasing the low end tork of the sad Chebby POS, it manages to pull 22,000#'s down the highway at 75-80 without too much problem with the 625 Road Demon, spreadbore to square ported adaptor and one of our 1/2" spacers and a pair of our Aramid Fiber Gaskets.
My 318 is up to 4.5" of 4 hole spacers, we started with 1" and started building at 11.83 .....after a dozen test passes and carb tuning the spacers got it down to 11.62.
The 1 hole spacers add plennum volume for top end MPH. I run the Victor manifold and as soon as we can get back to the track I'll be adding a 2" 1 hole spacer to see if we can get it run faster than the 115.08 MPH and still maintain the low 11.60's ET.
Rule of thumb for spacers:
Bonneville Salt Flats...1 hole spacers
Drag strip or towing 4 Hole
We've also got a 1 piece 1/2" and 1" all billet 6 pack - 6 hole spacer now available and we're having the Aramid .188 (3/16) gaskets CnC'd
to mount it. We're also working on the same spacer for the BG 6 shooter carbs, which will soon be available for Mopars. We will introduce the complete kit with hardware sometime in January.
We also have another new product..
4 hole spacer with a built in air bleed, very similar principle to the Demon EZ Idle Valve. It's cross drilled with a single air bleed screw to control air flow into the primary venturi to add air without over exposing the tansfer slot. It should also be available in the next 2-3 weeks.
Visit our web site for other new products that we've worked on this winter...Racer Brown Rocker arms BB and SB in 1.5 and 1.6 combo kits, Racer Brown Cam specs and tuning guide for various cam durations, Stewart Warner Gauges, Digital Shift lights with 4 speed shift recall memory, Round all Al. fuel cells that fit in the spare tire well for Mopars, Deep sump NEW gas tanks, MSD bushing kits to get you 20-24-26* initial timing, Foam coated stainless steel engine
gaskets NO MORE SILICONE!
There's lots more in the catalog and tech sections
www.4secondsflat.com
We haven't been sitting around this winter....LOL
