Hey. In the last issue of Chevy High Performance they built a motor that eventually incorporated a 2" 'tapered spacer'. Would that be a double taper to produce a sort of venturi effect? Otherwise, in what way would a taper be benificial? Just interested. Thanks!
Jon

JSD MOD <12/06/08>

 

A tapered spacer (IIRC!) isn't a double taper, but just a single. But you're right, it is intended to produce a venturi effect. 4 hole spacers are typically used to "speed up" the airflow, while large open spacers would be used to "slow down" the airflow. It's a tuning tool, every engine will require a different spacer depending on the RPM you want to make power. Hard to say it will help you, it might take away 15HP from your usable range.

One of those parts where you want to have 4-5 of them on hand while you have a 3hr dyno session to find out.

Key point - do you even have room to install one??

 

typically a group of buddies will buy several different ones and try out each combo at the track to see what the motor wants, then sell off the extra on ebay, etc.

 

Very good idea !

 

No space to install one at all. Until recently,I was running a 1/2 " spacer to adapt my Holley to the stock , spread bore manifold. Even with the drop base filter housing it put my air filter into the insulation blanket. My question was really asked for the purposes of my own education. That's what's so great about this site. A free education and I didn't have to join the army!
Thanks,
Jon

 

I will be changing over my Performer RPM intake to a lower version (with EGR for emissions) like the plain Performer or Weiand 8000. I plan on testing different 1" spacers to compensate for the loss of plenum volume. I'm thinking that the smaller Performer intake will boost my torque, but lose on the higher HP. So my first test will be with a 1" open spacer to see if that will help bring back the higher range HP.