September 2000: Bill Davis has purchased the TPI project, which is now finished. It's looking pretty good, and a "show & tell" at the local parts shop has brought rave reviews. Essentially, about an inch and a half of the SLP runner has been opened up into part of the plenum, shortening the runner length to 15.5 inches. This ought to help improve the top-end of the system. Since the runner itself is still fairly small, airflow velocity should still be high enough to preserve low-end response. 
I'm not currently porting materials for folks. I need time to finish my own projects. Sorry!  You'll have to convince me otherwise but it wont be easy or cheap!  ;) 
 

 
 
 
Here is the plenum, after gasket matching to a modified set of TPIS wide-mouth gaskets. The SLP runners require that you make radical changes to the plenum in order to make them work well. Otherwise, you end up with a large area of turbulence as airflow exits the plenum into the runner.

 
I use an aluminum specific carbide burr for all rough work: I use a cylindrical burr for convex shapes, a football shaped burr for concave shapes, and a conical burr for tight radius.
The intake is being modified.  There isn't a lot of material so I have to be quite careful when raising the roof, and enlarging the sides. I have increased the diameter of the passage throughout the whole length, which is a rather tedious process. It requires about two hours per passage for a total of 16 hours per intake manifold. 
The manifold / cylinder interface has been match ported to a Fel-Pro gasket set.  In addition, approximately .100" material has been ground from the roof of the port to aid in smoothing the radius.  The walls between the ports have also been thinned to straighten out the port as much as possible.  There is also a lot of work involved with opening up the port through it's whole length, and making the transition from cylindrical to rectangular shape.
The runners have also been modifed. SLP casts a slot that "siamese" the runners. I've enlarged the slot and widened the runner opening to fit a modified set of TPIS "wide mouth" gaskets. This has the effect of making the first 1.5 inches of the runner act as part f the plenum. The runner itself is now, effectively reduced from 17 inches to 15.5 inches. This should help move the torque peak up a few hundred RPM.
The 48mm throttle body has been reconditioned, and bored to 52mm. An aerofoil has been added to the throttle body to aid in airflow management. When you crack open the throttle blades, all you see inside the plenum is a wide, black maw with no restrictions anywhere. This system should flow enough air for most 305's, 350's, and torquer 383s. 

Page last updated 16 Jan 2003